- Eggplant Problems: Eggplant Pests And Diseases
- Growing Eggplant
- Dealing with Eggplant Pests
- Eggplant Diseases in the Garden
- What’s Eating My Vegetables?
- Signs and Symptoms of Insects and Slugs
- Damage by Wildlife (Vertebrates)
- Other Vertebrate Pests in the Garden
- Connect With Us!
- 1. Bacterial Wilt/Southern Wilt (Ralstonia solanacearum)
- 2. Cercospora Leaf Spot (Cercospora spp.)
- 3. Damping Off (Pythium spp., Fusarium spp.)
- 4. Alternaria Rot (Alternaria alternata)
- 5. Anthracnose Fruit Rot (Colletotrichum spp.)
- 6. Fusarium Wilt (Fusarium oxysporum f. sp. melongenae)
- 7. Verticillium Wilt (Verticillium spp.)
- 8. Phytophthora Blight (Phytophthora spp.)
- 9. Southern Blight (Sclerotium rolfsii)
- Pepper & Eggplant Disease Guide
- Pests of Eggplant
- Eggplant Flea Beetle
- Insect Pest Management in Eggplant
- Need Help?
- Natural Pest Control Methods
- नए लेख
Eggplant Problems: Eggplant Pests And Diseases
Eggplant is a commonly grown warm-season vegetable noted for its great flavor, egg shape and dark violet color. Several other varieties can be grown in the home garden as well. They consist of various colors and sizes, all of which can add unique flavor to many recipes or as stand-alone side dishes. Eggplant problems and eggplant pests can occur from time to time when growing eggplant; however, with the proper care, they can usually be prevented.
Eggplants are cold sensitive and shouldn’t be placed in the garden too early. Wait until the soil has sufficiently warmed and all threat of frost has ceased. These plants require full sun and well-drained soil amended with organic matter.
When growing eggplants, space them about a foot or two apart, as they can become rather large. Since eggplants are susceptible to many pests and diseases, the use of collars or row covers on young plants may be necessary to reduce common eggplant problems.
Dealing with Eggplant Pests
Lace bugs and flea beetles are common eggplant bugs. Other eggplant bugs that affect these plants include:
- tomato hornworms
The best way to deal with eggplant bugs is by using collars and row covers until the plants are large enough to withstand attacks, at which time insecticidal soap can be used to alleviate pest problems.
To prevent eggplant bugs, it may also help to keep weeds and other debris to a minimum and rotate crops every other year or so. Introducing natural predators, such as ladybugs, often helps minimize eggplant problems associated with aphids.
Eggplant Diseases in the Garden
There are several eggplant diseases that affect these crops. Some of the most common include blossom end rot, wilt diseases, and various types of blight. Many of these eggplant diseases can be eliminated or prevented by practicing crop rotation, reducing weed growth, and providing adequate spacing and uniform watering.
- Blossom end rot, as found in tomatoes, is caused from fungus due to overwatering and affects ripe fruit. Round, leathery, sunken spots appear on fruit ends with the affected fruit eventually dropping from the plant.
- Bacterial wilt can cause plants to suddenly droop, from the bottom to the top, turning yellow. Affected plants eventually wither up and die.
- Verticillium wilt is similar to bacterial wilt but is caused by soil-borne fungal infections. Plants may become stunted, turn yellow, and wilt.
- Southern blight is also caused by fungus and plants exhibit softening of the crown and root tissues. Mold may also be seen on the stems and surrounding soil.
- Phomopsis blight usually affects fruits of eggplant, which begin as sunken spots that eventually enlarge and become soft and spongy. Leaves and stems, especially seedlings, may develop gray or brown spots first.
- Phytophthora blight, which also affects peppers, can quickly destroy eggplants. Plants will get dark streaks prior to collapsing and dying.
Eggplants demand rich soil, even consistent water, warm temperatures, bonus side-dressings of nutrients, and little or no wind.
They can be difficult to grow without these ingredients.
Here is a troubleshooting list of possible eggplant problems with control and cure suggestions: (More eggplant growing success tips are at the bottom of this post.)
Eggplant Growing Problems and Solutions
• Seedlings are cut off near the soil surface. Cutworms are gray or brown grubs that hide in the soil by day and feed at night. Handpick grubs from the soil around plants. Keep the garden free of plant debris. Place a 3-inch cardboard collar around the seedlings stem and push it 1 inch into the soil.
• Leaves roll downward but there is no yellowing or stunting. Physiological leaf roll, not caused by pathogen; it may be a reaction to temperature or weather. Keep plants evenly watered. No action needed.
• Leaves deformed, curled, and discolored; plants are stunted. Aphids are small soft-bodied insects–green and gray–that cluster on undersides of leaves. Aphids leave behind a sticky excrement called honeydew; black sooty mold may grow on honeydew. Spray away aphids with a blast of water; use insecticidal soap; aluminum mulch will disorient aphids. Aphid predators include lacewing flies, ladybugs, and praying mantis.
• Leaves wilt, turn yellow, then brown. Whiteflies are tiny insects that will lift up in a cloud when an infected plant is disturbed. These insects suck juices from plants and weaken them. Spray with insecticidal soap. Trap whiteflies with Tanglefoot spread on a bright yellow card.
• Leaves appear scorched and wilted. Leafhoppers are green, brown, or yellow bugs ⅓-inch long with wedge-shaped wings. Leafhoppers suck juices from leaves and stems. Spray with insecticidal soap or dust with diatomaceous earth. Cover plants with floating row covers to exclude leafhoppers.
• Shoots are white or yellow stippled; thin, fine webbing appears on underside of leaves. Spider mites suck plant juices causing stippling. Spray with water or use insecticidal soap or rotenone.
• Tiny round, shot holes in leaves; lower leaves are affected more than top ones. Flea beetles are tiny black beetles that feed on leaves and jump when disturbed. Handpick beetles and destroy. Keep the garden free of plant debris. Cultivate the soil deeply to destroy larvae in early spring and interrupt the life cycle.
• Leaves are eaten and plants are partially defoliated. Blister beetles and tomato hornworms eat leaves. Handpick insects and destroy. Keep the garden weeds and debris. Cultivate in spring to kill larvae and interrupt the life cycle. Pick off beetles by hand. Spray or dust with Sevin or use a pyrethrum or rotenone spray.
• Leaves and shoots are stripped. Colorado potato beetle is a yellow beetle ⅓ inch long with black stripes and an orange head. Handpick off beetles. Keep the garden free of debris. Spray with a mixture of basil leaves and water.
• White, frothy foam on stems. Spittle bugs are green insects that can be found beneath the foam. Handpick and destroy. They do not cause significant damage and can be tolerated.
• Lower leaves wilt; leaves on one side of plant wilt; yellow patches on leaves. Fusarium wilt or eggplant yellows are a fungal disease which attacks plant roots and spreads into the plant’s vascular system. Plant in well-drained soil. Rotate crops. Remove and destroy infected plants; older plants may be harvested and then uprooted and thrown away.
• Lower leaves yellow and die; stem is discolored with brown streaks when the stem is split lengthwise; plants wilt and die. Verticillium wilt is caused by a soilborne fungus. Plant verticillium-resistant varieties. Rotate crops and avoid planting in soil previously planted with pepper, potato, tomato, or cucumber family members.
• Leaves are mottled and streaked yellow and green; leaves curl and crinkle. Mosaic virus has no cure. It is spread by beetles. Plant tobacco mosaic virus-resistant varieties. Destroy infected plants and keep weeds down that host cucumber beetles. Wash your hands if you are a smoker.
• Leaves turn yellow then brown; brown to nearly black spots appear on leaves and lower stem. Early blight is a fungal disease spread by heavy rainfall and warm temperatures. Keep weeds down in the garden area; they harbor fungal spores. Avoid overhead watering.
• Galls or knots on plant roots; plants wilt in dry weather; plants become stunted. Root knot nematodes are nearly microscopic, translucent worms that inject toxins and bacteria into plant roots. Plant resistant varieties labeled VFN varieties. Feed plants with fish emulsion which seems to counter nematode toxins. Rotate crops. Companion plant with marigolds.
• Leaves and stems have irregular greenish water-soaked spots; whitish-gray growth appears on the underside of leaves; fruit takes on a corrugated look. Late blight is a fungal disease brought on by a rainy period followed by heat and humidity. Keep the garden clean and free of weeds. Remove infected plants. Improve soil drainage.
• Plants have lush foliage do not fruit or have little fruit. The soil may be nitrogen rich and lack phosphorus. Add aged compost to the planting bed before planting and side dress plants with aged compost. If night temperatures are cool place a wire cage around eggplants and drape the cage with plastic at night. Increase pollination and fruit production by lightly tapping plants to make sure pollen is distributed.
• Blossoms fall without producing fruit. Blossoms may fall if the temperature drops much below 60°F or rises above 75°F. Plant early varieties or varieties recommended for your region. Plant in warmer weather.
• Plants do not grow, appear stunted; blossoms drop off; fruit does not develop. Temperatures are too cool, below 40°F. Set out the plants when the air temperature remains above 65°F, or protect plants with plastic jugs with the bottoms cut out or other protective devices. Plant when the weather is warmer. Plant varieties recommended for your region.
• Buds and blossoms have holes; young fruits may have holes or drop; mature fruit can become misshapen and blotchy. The pepper weevil is a dark beetle ⅛ inch long; the larva is a white, legless grub found inside fruit. Handpick weevils and grubs. Nightshade plants host the pepper weevil; destroy infested plants after harvest. Cultivate the soil to interrupt the pest’s life cycle.
• Fruit is normal-colored but small and flattened; there are few or no seed inside. Pollination was poor or incomplete. Plant when the weather has warmed and insects are active. Attract bees and other pollinators to the garden. Increase pollination and fruit production by lightly tapping plants to make sure pollen is distributed.
• White spots on fruit; leaf tips are distorted. Thrips are tiny insects, yellow, brown or black with fringed wings. They scrape plant tissue as they feed leaving a scar. Keep garden free of weeds. Spray with insecticidal soap or sprinkle diatomaceous earth on leaves.
• Sunken, water-soaked spots develop on blossom end of fruit; spots can turn black and mold may appear; patches may appear leathery. Blossom end rot is caused by irregular watering or the irregular uptake of water by plants; this can happen when temperatures rise above 90°F. Keep soil evenly moist; mulch around plants. The soil may have a calcium imbalance that inhibits the uptake of water; add limestone to the soil if the pH is below 6.0.
• Sunken water-soaked areas on fruit and stems; fruit may become watery and collapse. Anthracnose is a fungus disease that over-winters in infected seed and the soil. Destroy rotting fruit; keep fruit off soil. Spray or dust with a fixed copper- or sulfur-based fungicide every 7 days. Do not collect infected seed.
Eggplant Growing Success Tips:
Planting. Grow eggplant plant in full sun sheltered from the wind. Eggplant prefers well-drained soil rich in organic matter; add aged compost to each planting hole.
Plant time. Plant eggplant when the soil temperature is at least 60°F, not sooner than 2 weeks after the last frost in spring. To jump start the season, sow eggplant indoors 8 to 10 weeks before setting it into the garden.
Care. Eggplant is finicky; there’s no getting around it. Keep the soil evenly moist, not too wet. Do not let the soil try out. Grow eggplant in organically rich soil and side dress plants with aged compost or compost tea 2 or 3 times during the growing season. Eggplant demands warm temperatures in the 70°s and 80°s. Growing eggplant against a stake or in a small tomato cage will ensure it does not fall or break when fruit is set and ripening.
Harvest. Pick eggplant when it is one-half to one-third its full size at maturity; make sure you know the variety you are growing–a mature eggplant can be anywhere from 2 to 10 inches long. If you press the skin with your finger and the skin springs back, the fruit is ready for harvest. A fruit fast its peak will lose its shiny color.
More tips: How to Grow Eggplant.
What’s Eating My Vegetables?
Do your vegetable plants have leaves with holes chewed in them? Are the holes big or small? Have entire plants been chewed down to the ground? Are your cucumbers and cabbages wilting? Are the leaves of beets, spinach or chard looking splotchy? Do some plants have little yellow spots? It takes some investigative work to find the culprits. The first thing to do is to look carefully at the damage and any signs left behind.
Signs and Symptoms of Insects and Slugs
If you see holes or ragged chunks of leaves disappearing and the damage has been occurring slowly, with a little feeding each night, beetles, caterpillars, earwigs or slugs may be the culprits. To distinguish among these four look for signs, or evidence, left behind.
Caterpillars leave fecal droppings under the leaves or around the damage. Droppings look like small “pellets”. Some caterpillars make webbing. Damage ranges from numerous small holes in leaves, to removal of large portions of the leaf. Cutworm caterpillars feed at night on both stems and leaves. During the day look for the curled up caterpillars just under the soil surface near plant stems.
Beetles are not as likely to leave droppings and they often escape notice by falling to the ground. They fall in response to leaves being moved as you look for them. Look carefully under leaves for signs such as egg clusters and tiny larvae. Since many different species and sizes of caterpillars and beetles appear in gardens, look for information on the plant that’s being chewed to determine what insect pests are typically associated with it.
The European earwig, found in New England gardens, can damage seedling vegetables, corn silk and soft fruit. They will chew numerous holes in the leaves of many kinds of vegetable plants. Younger leaves may have holes all over the leaf and older leaves tend to be chewed around the edges. Leaves chewed by earwigs often have a ragged look.
Slugs leave a coating of slime as they feed, which dries into a shiny trail. The slime helps protect their bodies from desiccation and a residue often remains where the slug has crawled.
To investigate further, look for pests at dusk, or with a flashlight at night. Many caterpillars, beetles, and especially earwigs and slugs, feed at night and hide during the day. Handpicking caterpillars, beetles and slugs and dropping them into soapy water can be effective in home vegetable gardens. Trap earwigs in shallow cans baited with fish oil or a drop of bacon grease in vegetable oil.
Damage Caused by Piercing-sucking Insects
If you see plants with wilted, drooping leaves or with small yellow spots, look carefully for tiny, soft-bodied insects in groups along the stems or under the leaves. Aphids, whiteflies and squash bugs have mouthparts like a microscopic straw. They feed by poking their mouthparts into a leaf or stem and sucking out nutritious plant juices. This process leaves yellow patches or spots. Aphids and whiteflies don’t grow more than about 1/8” long. Look for a sticky residue, called “honeydew” on leaves below or close to where they feed. This residue often becomes sooty with mold.
Squash bugs emerge from bronze colored eggs usually laid in clusters on the bottom surface of squash leaves. About 1/8” long, grey and soft at first, they grow into brown, hard-shelled adults nearly 3/4” in size. Aphids and whiteflies feed mostly in one place, while squash bugs move around on the plant, frequently under the leaves.
Leaf-mining, Root-feeding and Stem-feeding Damage
Winding, tan colored blotches on the leaves of spinach, beets and Swiss chard leaves indicate the presence of leaf miners. These tiny fly larvae tunnel between the surfaces of the leaf and leave the splotchy trails called “mines”. You can pull off the top surface of a mine and find the find the little white maggot, if it is still active. The adult fly lays its eggs on the surface of a leaf, then the larvae tunnel into the succulent insides of the leaf to feed.
Are your cabbage seedlings wilting? The cabbage root maggot fly, as well as the related onion maggot and seed corn maggot flies, lays eggs in the soil near the host plant (or seed) and the emerging larvae tunnel into the roots or seeds. Plants affected include broccoli, cabbage, cauliflower, radishes and other plants in the cabbage family, as well as onions, vine crops (cucumbers, squash, pumpkins, melons and gourds), and corn, pea and bean seeds. The adults look like small houseflies. The larvae, or maggots, do the damage by feeding and tunneling. Damage can cause wilting, poor germination, render radishes unappealing and cause onions to rot.
Cucumber seedlings that wilt, turn yellow and potentially die could be infected with a bacterial wilt disease (Erwinia tracheiphila) transferred by cucumber beetles. Look for tiny, ¼” long yellow and black striped, or black spotted yellow, beetles feeding on the young leaves of vine crops (cucurbits). Both the striped and the spotted cucumber beetle are found in Massachusetts. Their damage includes feeding on stems, leaves and roots as well as transmission of the wilt disease. Seedlings with less than five leaves are most vulnerable.
As squash plants begin producing fruit you might notice the leaves wilting. Look back along the stem from the wilted leaf for excrement, called “frass”, which looks like sawdust left by the insect feeding inside the stem. Make a lengthwise slit in the stem near the frass to look for the large, cream-colored caterpillar eating inside the stem. Remove the caterpillar, and then cover the damaged portion of the stem with several inches of soil to encourage rooting. Watch for the orange and black adult moth, which flies like a small hummingbird, hovering around squash plants during the day. The moth lays tiny, reddish brown eggs along the stems and on leaves.
Once you have diagnosed the cause of damage, consider how you will manage the problem. Depending on the amount of damage, you may choose to allow natural enemies to reduce the pest population, or to wash or pick the pests off the plants by hand. Plan to use lightweight row covers to protect crops from flies and beetles and from butterflies and moths that produce caterpillars. In many cases row covers, put in place at the time of planting, provide the best protection for seedlings of cabbage family plants and vine crops.
Some beetles and caterpillars can be managed in the vegetable garden using products containing Bacillus thuringiensis (Bt), neem (azadarachtin) or spinosad, which are made from natural ingredients. Insecticidal soaps, neem and other oil products may be effective as both a pesticide and/or a deterrent for soft-bodied insects. Early, immature stages of insects are always more vulnerable to treatment than later stages. Read the labels carefully and choose a product that is labeled for both the pest and the crop.
If you decide to use a pesticide, dusk is a good time to treat for active pests, for three reasons:
- Beneficial insects and pollinators are less likely to be active.
- In the absence of sunlight, active ingredients in organic pesticides degrade more slowly.
- Often the wind dies down at dusk, which minimizes spray drift.
Damage by Wildlife (Vertebrates)
Rabbits, Voles, Woodchucks, Deer, Chipmunks, Squirrels
All eat leaves or fruits of plants in vegetable gardens. Symptoms include:
- Large parts of the plant are chewed off
- Leaves are nibbled; stems cut
- New growth is uniformly nibbled off
- Plants are eaten to the ground
- Fruits are damaged or removed
To help determine what vertebrate animal is causing the damage, sprinkle a layer of finely ground limestone around the damaged plants and look for animal tracks left in the powder the next day.
Rabbit damage can be identified by foliage that has been nipped off sharply, leaving no ragged edges. Seedlings might be grazed to the ground, and new growth uniformly nibbled off. Look for pea-sized droppings in the vicinity. Rabbits don’t travel far from their burrows or resting places. They feed at dusk, in the night and early morning. They favor tender beans, beets, broccoli, carrots, lettuce and peas. Deer damage can be easily confused with rabbit damage, but usually large parts of plants are chewed off and deer tracks will be evident in the soil.
Voles damage seedlings by chewing leaves and stems. Vole damage can be confused with cutworm damage because voles will move down a row of seedlings eating just the stems and toppling plants. Or, they might nibble only on the leaves. They feed mostly at night. Look for vole tunnels in grassy areas at the edges of the garden. Voles stay close to their tunnels and sometimes tunnel right into the garden. Problems are more likely to occur when vole populations are high.
Woodchucks tend to trample plants as they feed. They feed close to their burrows during the day, especially in mid-morning and late afternoon. Like rabbits, woodchucks seek shelter in weedy areas, stonewalls, brush piles or under porches and outbuildings. They like corn, beans and peas, but will browse on many tender garden vegetables.
Chipmunks and squirrels may develop a taste for fruits, such as tomatoes or strawberries, more often than the leaves of vegetables. Watch your garden in early morning and at dusk for rodent activity.
To deter mammals, fencing or repellents can be used. A fence that is installed correctly and well maintained will deter many vertebrate pests, with the exception of birds. Different animals require different types and patterns of fencing for success. Electric fencing, at different heights and often in combination with other types of fencing may be required for certain animals. Because of the investment in labor and expense for fencing, plan ahead carefully. In general, proper fencing is the best way to protect your garden from vertebrate wildlife.
Depending on how many nuisance animals live near your garden, as well as their habits and preferences, repellents might be useful. Repellents must be applied frequently, consistently and after rain. Experiment with different kinds of repellents and rotate, or change, the type used. Animals tend to become less sensitive, over time, to the effect of a particular repellent. Ingredients in repellents may include animal predator urine, blood meal, garlic, sulfur or hot pepper, among others. Read the labels carefully and follow the directions.
Other Vertebrate Pests in the Garden
Raccoons are notorious for raiding the corn patch the night before you planned to pick your first succulent ears. First, try to be absolutely sure that no source of food, such as pet food, compost or garbage is accessible to raccoons in your neighborhood. Eliminate potential den sites in stonewalls, woodpiles, outbuildings or porches. Ordinary fences will not deter raccoons. Electric fences, properly installed, may deter them.
Birds will pull sprouted seeds of corn, peas and beans out of the ground. Row covers placed over vulnerable, newly seeded crops will deter birds. As for other animals, repellents (including “scare” tactics) have limited long-term value.
In Massachusetts it is illegal to trap and then transport animals to another location. For information on legal means for managing nuisance animals consult the Massachusetts Division of Fisheries and Wildlife.
Effective management of pests depends on accurate identification of what is causing damage. Once you know what pest is eating your vegetables, you can choose the best option for control. Consider cultural methods, habitat management, handpicking and barriers as a first line of defense. If you choose to use a pesticide select a material labeled for both the pest and the crop. To learn to identify pests and to find photos of some of the pests mentioned in this article, go to www.google.com and enter search terms for the plant and/or the pest, then click on images.
Connect With Us!
PHOTO: Michael Bentley/Flickrby Jessica Walliser August 12, 2014
Eggplants—much like their close cousins, tomatoes—are far tastier fresh out of the garden than purchased at the grocery store. Growing this amazing vegetable isn’t as complicated as you might think, though they do require warm temperatures, compost-rich soil, and regular watering for the greatest rate of success. Sadly, even when you give them everything they need, there’s a small chance that troubles may arise, often in the form of diseases.
A handful of bacterial and fungal diseases can strike your eggplant patch, causing blemished fruits, marred foliage, decreased production and sometimes plant death. Identifying and remedying these pathogens can be very challenging because many of them look alike. Your local cooperative extension service can recommend a plant pathology lab to confirm a specific diagnosis through a submitted sample. But regardless of which diseases might be waiting in the wings, when it comes to eggplants, an ounce of prevention is worth much more than a pound of cure.
To avoid fungal and bacterial diseases in the first place, be sure to rotate crops every year, give each plant plenty of space, remove all garden debris at the end of the growing season, avoid working in the garden when foliage is wet, choose varieties with proven disease resistance, and keep a close eye out for problems, especially during wet weather. Treatment with copper-based fungicides and/or bio-fungicides, such as Bacillius subtilis, might prove successful in battling some of these pathogens, but keep in mind that most of these diseases are best handled when symptoms are first spotted.
1. Bacterial Wilt/Southern Wilt (Ralstonia solanacearum)
Plants affected by this bacteria disease are in big trouble. Although it’s naturally found in tropical regions and greenhouses, the disease often arrives to the garden via purchased plants grown where the disease is present. It’s soil-borne but can be transmitted by soil, water, plant matter, and even on clothes and tools. Bacterial wilt attacks many common bedding plants and vegetables, including eggplants.
Initially only one or two leaves wilt during the day, while the remaining leaves appear healthy. As the infection spreads, more leaves wilt and yellow until the entire plant succumbs, despite the stem remaining upright. Lower stems might develop dark-brown splotches, and slimy, viscous ooze comes out of the stems when they are cut. If you take two freshly cut stems and hold the ends together for a few seconds, a thread of slime will connect them as they are separated. When cut stems are placed in water, milky streams of bacteria are seen streaming out of the cut.
Bacterial wilt can survive for long periods in the soil on roots and plant debris. Like many other diseases, it favors high temperatures and high humidity. Sadly, there’s no cure for this disease. Once confirmed, infected plants must be removed and discarded in the garbage. Keep them out of the compost pile.
2. Cercospora Leaf Spot (Cercospora spp.)
This fungal disease affects the leaves and stems of eggplant; the fruit remains unaffected. The first sign of this disease are small, circular yellow lesions on the foliage. Eventually the lesions develop soft, gray fuzz at the center with a dark-brown ring around the exterior. Sometimes concentric rings appear, hence the disease nickname “frog eyes.” In severe infestations, defoliation can occur, and fruit size and production is greatly reduced.
Cercospora leaf spot survives the winter in plant debris, and when spring arrives, the spores are spread by wind, rain, people and animals. To keep spores off plants, mulch newly planted seedlings with straw or hay to prevent infected soil from splashing onto the leaves.
3. Damping Off (Pythium spp., Fusarium spp.)
Young eggplant seedlings might succumb to damping off. Pythium species are the most common cause of this disease, resulting in dark, water-soaked lesions at the base of young seedlings or on developing leaves. Eventually, infected seedlings are girdled and fall over. These fungi can survive for long periods in soil, plant debris and weeds. Damping off is most severe when conditions are too wet or seedlings are overcrowded. Keep air circulating around seedlings and water from below whenever possible. Sterilize flats and pots before reusing them and remove any symptomatic seedlings to keep the disease from spreading.
4. Alternaria Rot (Alternaria alternata)
Eggplant fruits affected by this fungus develop small, gray, water-soaked lesions, often starting at the bottom end of the fruit or at a site of injury. Eventually, the lesions grow in size and produce fuzzy-looking patches of spores. They can occur on both immature and mature fruits. Discard infected fruits as soon as you notice them, and use an organic fungicide to prevent the disease from spreading to other fruits.
5. Anthracnose Fruit Rot (Colletotrichum spp.)
Sometimes called ripe fruit rot, this fungal disease often remains symptomless until the fruit is ripe and ready to harvest. The disease starts out as small, sunken, gooey spots that eventually merge into larger blotches. When spore-set occurs a few days later, concentric circles cover the lesions and orange or pink jelly-like patches of spores can be found covering the lesions. Prevent fruit from touching the soil, and harvest before they become overly ripe. Remove infected plants from the garden and throw away, and plant with disease-free seed.
6. Fusarium Wilt (Fusarium oxysporum f. sp. melongenae)
Fusarium wilt symptoms often begin with drooping leaf petioles. Sometimes a single branch may wilt before the rest of the plant. In eggplants, this wilting often starts with the lower leaves, quickly progressing up the plant until the whole thing collapses. The entire plant may be killed, often before it reaches maturity. If you cut the main stem of an infected plant, you can see dark streaks running lengthwise through the stem. You might see dark-brown, sunken cankers at the base of the plant.
The fusarium fungus survives in the soil for several years and is spread by equipment, water and plant debris. Like many other diseases, it favors warm soil and high moisture. If fusarium wilt has been a problem for you in the past, be sure to rotate crops and try growing in raised beds to promote good drainage.
7. Verticillium Wilt (Verticillium spp.)
Verticillium wilt is caused by a group of soil-borne pathogens that block the vascular system of the plant, causing it to wilt. Symptoms progress slowly in eggplants, often starting as a characteristic V-shaped lesion that develops on older leaf tips, eventually expanding to cover the entire leaf. As the disease progresses, the plant becomes chlorotic (i.e., doesn’t produce enough chlorophyll) and withers, eventually dying. Cutting through the main stem of the plant will reveal dark-brown discoloration inside.
Verticillium fungi can survive for many years in the soil and on plants. They prefer slightly cooler summer temperatures, between 70 and 80 degrees F. Because this organism resides in the soil, crop rotation and soil solarization are helpful in deterring it. Grafted eggplants are said to be more resistant.
8. Phytophthora Blight (Phytophthora spp.)
This fungal disease can strike either the root or the shoot system of the plant. If it enters via the roots, they quickly turn brown, causing the plant to die. Stem and leaf infections start as dark green, water-soaked lesions that turn dark brown and expand. As the lesions age, they dry out. Infection can spread to the fruits, causing the same, distinct dark-green lesions that appear on the stems and leaves. Often the fruit shrivels but doesn’t drop from the plant.
Heavy amounts of rainfall, wet soil, and poor drainage generally favor this disease.
9. Southern Blight (Sclerotium rolfsii)
This fungal disease can attack both seedlings and mature plants. In seedlings, it causes damping off at the soil level, while in mature plants, it can affect the entire plant, generating dark-brown stem lesions at or just below the soil line. Infected foliage yellows and eventually wilts. A distinct feature of southern blight is the fan-like webs of whitish fungal threads that develop around the rotted stems. Small, brown, hard, mustard seed-like masses (sclerotia) form in the “fans” of fungal threads. These masses overwinter in and around infected plant debris and can survive for many years. When conditions are right, the fungal mycelia within the sclerotia emerge and initiate a new infection. To help control southern blight in places where a previous infection has occurred, maintain a soil pH of 7 or above; the sclerotia are inhibited in slightly more alkaline conditions. Deep plowing is also effective.
Brinjal Pests and Diseases (Eggplant):
Let us discuss today Brinjal Pests and Diseases, symptoms, and their control methods.
Diseases of Brinjal:
Damping off: This disease causes severe damage to the plants. The main cause of this disease is high soil, moisture and moderate temperature with high humidity levels during the rainy season.
Pre-emergence damping-off: The pre-emergence damping off is observed in seed and seedling rot before they emerge from the soil.
Post-emergence damping-off: The post-emergence damping off will infect the young, juvenile tissues at the ground level. The infected tissues will become soft and water soaked.
Prevention: Select healthy and high-quality seeds. Treat the seed with Thiram seed before sowing. Soil solarization can be implemented by spreading polythene sheets over the bed for 30 days before sowing is effective to control damping-off to some extent.
This is a severe disease in brinjal that infects the foliage and the fruits. The fungus infects the seedlings causing damping off. The infected leaves have small circular spots appear which turn to brown causing blighting. The flesh of infected fruits will rot.
Prevention: Good sanitation, destroying the infected plant material and crop rotation help to reduce the spread of disease. Treat the seeds with Thiram and Spraying organic fungicides with Dithaneor Bordeaux will effectively control the disease.
Leaf spot: The disease symptoms are chlorotic lesions in angular to irregular shapes, later the lesion turns grayish-brown. Infected leaves will drop off leads to reduced yields.
Prevention: Remove and throw away the affected plant and Use organic fungicides with Bavistin or Chlorothalonil for disease control.
Alternaria Leaf Spots: The disease causes leaf spots with concentric rings. The spots are irregular and coalesce and cover large areas of the leaf blade. Severely affected leaves drop off. The infected fruits have large deep-seated spots. The infected fruits turn yellow and drop off prematurely.
Control: Destroy the affected plant parts and spraying the affected plants with Bavistin is useful to control the disease.
Fruit Rot: High humidity is the main cause of this disease. The symptoms of the disease are water-soaked lesions on the fruit, which later enlarges. The fruits infected with the disease will turn brown and develops white cottony growth.
Prevention: Destroy the affected fruits and spraying the crop with organic pesticides with Difolatanwill control the disease effectively.
Verticillium Wilt: This disease will infect the young plants and mature plants. The infected young plants show dwarfing and stunting. And infected plants do not flower and fruit. Plants infection after the flowering stage will produce distorted floral buds and fruits, finally results in drop off. The infected leaves have pale-yellow spots and wilting. The roots of the affected plants will split and changes its color.
Control: Crop rotation with okra, tomato, the potato should be avoided.
Bacterial Wilt: Bacterial wilt is a serious disease in brinjal cultivation. The symptoms of this disease are wilting and dropping of leaves. The wilting is gradual, first, the foliage starts yellowing, and then withering and finally drying of the entire plant.
Control: Destroy the affected plant parts and use disease-resistant varieties to prevent disease. Avoid crop rotation with bhendi, tomato, potato. Treated seed with Streptocycline before sowing.
Little Leaf of Brinjal: This is a viral disease of brinjal. This is a disease spread by a leafhopper. The leaves of the infected plants turn to light yellow. The size of the infected leaves will shrink. The affected plants are shorter in stature with heavy foliage, roots, and leaves than the healthy plants. The flower parts get deformed, leading the plants to be sterile. Infected plants don’t produce fruits or sometimes produces immature fruits.
Prevention: Good sanitation. Destroy infected plants. Use organic pesticides with Malathion will control diseases and leafhopper.
Mosaic: This is a viral disease transmitted by aphids. The symptoms of the disease are mosaic, mottling on the leaves and stunting of plants. The leaves of diseased plants are deformed, small and leathery. Plants show stunted growth.
Control: The disease effect can be reduced by minimizing the population of aphids, removal, and destruction of infected plants and eradication of susceptible weed hosts. Spraying organic Phosphamidonwill effectively control the aphids in the field.
Read:Frequently Asked Questions About Plant Diseases.
Pests in Brinjal:
Shoot and Fruit Borer: This pest created serious damage to the leaves, flower buds and fruits. The short pinkish larva will be induced into terminal shoots which results in withering and drying of the shoot.
Prevention: Implement crop rotation. Clip of the affected as soon as you find the infected part. Fruits with boring should be removed immediately. Use organic pesticides in a combination of Carbaryl (0.1%) or Cypermethrin (0.5ml/liter of water) after transplanting to control the pest.
Leaf Eating Beetle: The pale yellowish colored grubs and adult insects that feed on the leaves and tender parts of the plant can cause serious damage to the plant.
Prevention: Destroy the infested leaves along with the grubs, adult, and eggs, which reduced the pest incidence. Use liquid organic insecticides with Malathion or Carbaryl to control the pest.
Jassids: The nymphs and adults will suck the sap of the leaves. The affected leaf will curl upward along the margins and turn to yellow color with burnt up patches. This insect also transmits little leaf and virus disease like a mosaic. Fruit yields are highly affected by the infestation.
Prevention: Jassids are controlled by spraying liquid organic pesticides with Malathion or Dichlorvos after 15 to 20 days of transplanting.
Leaf Roller: These caterpillars will roll leaves and feed on chlorophyll. The leaves get folded, wither and then dry up.
Prevention: destroying the infested leaves along with insects at the initial stage can minimize the infestation to some extent. Use organic insecticides with carbaryl or Malathion to control the pest effectively.
Red Spider mites: Most common pests of brinjal plants. This is infected due to low humidity levels. Nymphs and adults will suck sap and form white patches on the leaves. The leaves will become mottled, turn brown and fall.
Control: During high temperatures use organic insecticides with Dicofol and Wettable Sulphur which gives effective control of mites. Removing the severely infested plant parts can reduce the multiplication of mites. Proper irrigation and clean cultivation will keep the pests under control.
Mealy Bug: Nymphs and adults will suck sap from the leaves, tender shoots, and the fruits. The leaves will curl and wither. This pest form heavy black sooty mold may develop on the honeydew-like droplets. Leaves, flower blooms, and fruits are mainly affected by mealy bugs. The affected fruits are entirely covered with the mealybug. And leads to fruit drop or the fruits remain on the shoots in a dried and shriveled condition.
Prevention: Spraying organic insecticides with Dichlorvos Chlorpyriphos and fish oil rosin soap is the best method to control pests.
Lace Wing Bug: This pest mainly attacks in the summer season. Nymphs and dark brown bugs will suck the sap from leaves, and leaves turn yellowish and will be covered with excreting. Affected leaves will dry up.
Prevention: Crop rotation and using organic pesticides with Phosphamidon will help in the reduction of the pests.
Root-Knot Nematodes: this pest will cause severe damage to seedlings than the older plants. The affected plants will develop galls on the roots. The fruits are highly infested and drop off.
Prevention: Crop rotation, rotating the nematode resistant crop. Treating soil beds with Aldicarb or Carbofuran will increase the seedling growth and reduce the nematode.
Read: Mud Crab Culture.
Bottom Line: Commercial Brinjal/Eggplant growers must know the most common Brinjal Pests and Diseases affecting the crop.
Pepper & Eggplant Disease Guide
- Bacterial Canker
- Bacterial Spot
- Bacterial Stem & Peduncle Canker (Soft Rot)
- Bacterial Wilt
- Syringae Seedling Blight & Leaf Spot
- Cercospora Leaf Spot (Frogeye)
- Choanephora Blight (Wet Rot)
- Damping-Off & Root Rot
- Fusarium Wilt
- Gray Leaf Spot
- Gray Mold
- Leaf Spots
- Phomopsis Blight
- Phytophthora Blight
- Powdery Mildew
- Southern Blight (Sclerotium Wilt)
- Verticillium Wilt
- White Mold (Pink Rot, Watery Soft Rot)
- Blossom-End Rot
- Chemical Damage
- Nutrient Disorders
- Salt Toxicity
- Pepper and Eggplant Aphids
- Eggplant Fruit and Shoot Borer
- Pepper and Eggplant Beetles
- Pepper and Eggplant Leafhoppers
- Pepper and Eggplant Mites
- Pepper and Eggplant Whiteflies
- Pepper and Eggplant Plant Thrips
- Little Leaf Phytoplasma
- Alfalfa Mosaic
- Beet Curly Top
- Chilli Veinal Mottle
- Cucumber Mosaic
- Pepper Mottle
- Pepper Yellow Mosaic
- Potato X
- Potato Y
- Tobacco Etch
Pests of Eggplant
Eggplant Flea Beetle
Skip to Eggplant Flea Beetle
Eggplant flea beetle, Epitrix fuscula Crotch, Chrysomelidae, COLEOPTERA
Adult – The oval, black, 2 mm long beetle has thickened, jumping hind legs. Its antennae are 2⁄3 the length of its body. This species resembles the potato flea beetle but has black legs and slightly hairy wing covers.
Egg – Generally elliptical in shape, the egg is 0.4 mm long, 0.2 mm wide, and pointed at one end. Though white at first, it gradually becomes yellowish-gray.
Larva – A typical flea beetle larva is white with a brown head and three pairs of brown legs near its head. This species is 4 to 5 mm long when fully grown.
Pupa – Shaped roughly like adults, pupae are found in the soil. They are white at first but gradually darken.
Distribution – Occurring throughout most of this country, eggplant flea beetles tend to be most common in southern states.
Host Plants – This flea beetle has a narrow host range. Reports of its occurrence have been limited to eggplant, potato, horsenettle, pokeweed, sugar beet, and strawberry.
Damage – Feeding on new growth as it appears in spring, flea beetles can be very destructive to young plants. They leave foliage riddles with holes, the edges of which turn brown giving plants a diseased appearance. Though older leaves often withstand this injury, younger leaves may be killed. Flea beetle larvae feed on roots and may cause damage to tuber crops such as beet and potato.
Life History – Eggplant flea beetles overwinter as adults in soil or crop debris. Their life cycle has not been studied in North Carolina, but in Indiana they emerge from hibernation in mid- to late March. Weedy hosts such as horsenettle and pokeweed are infested until crop hosts become available. Eggs laid in soil near the bases of plants hatch in about one week. Larvae emerge from the eggs and feed on roots or tubers for 2 to 3 weeks. After developing through three instars, larvae pupate in the soil. The pupal stage lasts 7 to 10 days. Beetles emerge from the pupal skins, make their way out of the soil, and feed on leaves for 2 months or more. As a rule, flea beetles complete one to four generations each year. In North Carolina, there are probably three or four annual generations.
Cultural practices such as destruction of crop residue, weed control and late planting help minimize flea beetle problems. The removal of crop residue reduces the number of favorable overwintering sites for flea beetles. Covering plant beds and destroying trash around them also is beneficial. Control of weeds such as horsenettle and pokeweed around garden sites eliminates important early beetle food sources. Delayed planting favors the development of host plants over the establishment of flea beetles.
A number of insecticides (granular and foliar) are available to control adult flea beetles. For recommended chemicals and rates of application, consult the current North Carolina Agricultural Chemicals Manual.
A. Eggplant flea beetle. B. Flea beetle larva. C. Flea beetle pupa.
A. Eggplant flea beetle. B. Flea beetle larva. C. Flea beetle pupa.
Insect Pest Management in Eggplant
While eggplant production in Maryland is rather small, they are grown over the entire state to supply vegetable stands with many varieties. Because of its value growers frequently apply pesticides regularly in order to protect their investment. This often leads to development of insect resistance, environmental contamination, worker and food safety issues and poor management of a pest. The key to any successful pest management program is to develop a regular scouting plan to gain information on insect pest populations that may be used to determine if insecticide applications are needed. Monitoring can consist of sampling groups of 10 plants which are randomly selected at a minimum of 4 different locations in a field. Samples should be evenly distributed throughout the field so that plants near the edges and middle of the field are examined. It is critical to properly identify the pest to be controlled and to determine its potential for damage. The only way to obtain this information is through routine scouting of fields. The purpose of this guide is to serve as a reference for insect pest identification and for general management guidelines. Specific information on insecticides is available from EB-236 the pesticide recommendation guide for the mid-Atlantic region. Cultural controls, reduced risk pesticides as well as other pesticides are recommended for each pest.
Colorado Potato Beetle (Leptinotarsa decemlineata) (CPB) is a serious insect pest of potatoes but will also attack eggplant, tomato and pepper in that order of preference. Both the adult striped beetle and the black-spotted, hump-backed red larva are foliage feeders. Their feeding damage can greatly reduce yield and in some cases kill plants. The Colorado potato beetle has the ability to rapidly develop resistance to insecticides that are used repetitively for their control. This has been a serious problem on the east coast for many years. Colorado potato beetles overwinter as adults in the soil. They become active in the spring as temperatures rise and begin to feed on weeds or early planted potatoes. Female beetles lay elongated oval orange-yellow eggs on the underside of foliage. Each female can lay 500 or more eggs over a 4-5 week period. Eggs hatch in four to nine days and the larvae begin to feed on eggplant foliage. They usually feed in groups and damage can be severe. The larval stage lasts two to three weeks. Full grown larvae burrow in the ground to pupate. In five to 10 days, the adult beetle emerges. This insect can go from egg to adult in as little as 21 days. The newly emerged adult female feeds for a few days before egg laying begins. There are two full generations each year.
Management. Insecticides in the same chemical class usually have the same method of killing the insect. Resistance develops more rapidly when that insecticide is used repeatedly as the only control measure. Overuse of one insecticide may favor the development of resistance to other insecticides in the same chemical class. Consequently, to delay or prevent resistance it is important to avoid repeated use of one particular insecticide by rotating insecticides (see EB-236, CPB under white potatoes). Timing of sprays is critical for control. Overwintering beetles are attracted to fields over a period of several weeks; in the early season adults do not fly, but must walk to the nearest food source. That is why rotating at least ¼ mile away works so well. Eggplant plants can withstand considerable defoliation (20%) without yield loss. Generally, insecticides do not need to be applied unless there is more than one beetle or larva per plant. Btt Bacillus thuringiensis tenebrionis (Novodor) is the organic chemical that controls only small CPB larvae and should be first applied when 30% of CPB eggs hatch followed by applications on a 5-7 day schedule. Another organic chemical control is Entrust, it works best on small to medium size larvae, but will control larger larvae to some degree. Reduced risk pesticides for CPB control are: imidacloprid, or Platinum at-planting. DO NOT use any of the at-planting chemicals again during the season. Foliar chemicals include Actara, Assail, Rimon, SpinTor or Radiant.
Flea Beetles. All solanaceous plants are susceptible to flea beetle attack, but eggplant is especially vulnerable and to a lesser extent pepper and potato. There are many different species of flea beetles that will attack solanaceous and cruciferous crops. The more common species that attack solanaceous plants are the eggplant (Epitrix fuscula), tobacco (Epitrix hirtipennis) and potato (Epitrix subcrinata) flea beetles. The eggplant flea beetle adult is an oval, black; 1/10 inch long beetle that has thickened, “jumping” hind legs. Its antennae are about 2/3 the length of its body. This species resembles the potato flea beetle but has black legs and slightly hairy wing covers. The potato flea beetle is also about 1/10 inch long and brownish black. The tobacco flea beetle is about the same size, but is yellowish brown with a dark band across its wings. All eggs of these species are <1/250 inch long and pointed at one end. Though white at first, they gradually become yellowish-gray. A typical flea beetle larva is white with a brown head and three pairs of brown legs near its head. Larvae become 1/16 inch long when fully grown. In general, flea beetles overwinter as adults in soil or crop debris and emerge from hibernation in mid to late March. Weedy hosts such as horsenettle and pokeweed are infested until crop hosts become available. Eggs laid in soil near the bases of plants hatch in about one week. Larvae emerge from eggs and feed on roots for 2 to 3 weeks. After developing through three instars, larvae pupate in the soil. The pupal stage lasts 7 to 10 days. Beetles emerge from the soil and feed on leaves for 2 months or more. Flea beetles complete 1-3 generations each year in Maryland. Adult flea beetles feed on both leaf surfaces but usually on the underside where they chew small, circular holes through to the upper cuticle, which frequently remains in place for a time before falling out. The circular holes give the plant a “shotgun” appearance; large numbers of these shotgun holes may destroy entire leaves. Flea beetles can be serious pets early in the season when plants are small, less than six inches tall. As plants grow larger they can withstand substantial flea beetle damage without loss of yield. Flea beetle larvae feed on roots where they seldom cause any yield loss to eggplant.
Management. Cultural practices such as destruction of crop residue, weed control and late planting help minimize flea beetle problems. The removal of crop residue reduces teh number of favorable overwintering sites for flea beetles. Controlling weeds such as horsenettle and pokeweed around field sites eliminates important early beetle food sources. Delayed planting favors the development of host plants over the establishment of flea beetles. If defoliation becomes becomes severe on small or medium sized plants one application with pyrethroid will usually take care of the problem. There are no good organic chemicals available that will control flea beetles.
Tomato Fruitworm (Helicoverpa zea) is a minor problem in eggplant, usually after corn has dried down in the area. The larvae are variable in color, ranging from pale yellow, to red, to green, to brown with pale stripes running lengthwise. Young larvae have several rows of black bumps along their backs and two bristle-like hairs in each bump. Older larvae are densely covered with microscopic spines that make them feel rough. Fruitworms overwinter as pupae in the top 2-6 inches of soil. Adults emerge from early May to early June and have 2-3 generations per year in Maryland. The moths lay eggs at night on leaves near fruit. Eggs are white when first laid and develop a reddish brown band 24 hr before hatching. After the egg hatches, the larvae feed for a short period of time on the foliage before attacking the fruit. Damage consists of small holes in the stem of the fruit when larvae are small but the larvae are cannibalistic, so there is rarely more than one larva per fruit. The tomato fruitworm has a wide host range and the attractiveness of eggplants for egg laying vary with the time of year. The most severe fruitworm damage in eggplants frequently occurs after dry-down or harvest of adjacent corn as eggplant now becomes a site for egg laying.
Management. Calendar-based insecticide sprays are not recommended. Though it may appear that a calendar-based program is a preventative strategy this program is not cost-effective. A more effective strategy for managing fruitworm and armyworms is to monitor fields regularly for signs of the pests or their damage and to apply an insecticide only when necessary, i.e., at 10% infestation or 5% fruit damage. Field trials in Maryland have demonstrated that use of the insect monitoring program will reduce pesticide applications and any damage by the pest. Reduced risk chemicals for fruitworm control include: Avaunt, Confirm, SpinTor, and Proclaim. Other chemicals include: Pyrethroids, Renounce, and Coragen.
Yellowstriped Armyworm (YSA) (Spodoptera ornithogalli) and Fall Armyworm (FAW) (Spodoptera frugiperda)become pests later in the season in eggplant. YSA larvae usually have a yellow or cream colored strip running along the length of their body which can be pale gray to black. On the first abdominal segment there are two large dark spots. FAW larvae vary in color from light tan or green to nearly black. Along the sides of its body is a longitudinal, tan or yellow stripe; while down the center of its back is a reddish-brown stripe. The head of the fall armyworm is usually marked with a pale-white inverted “Y.” Eggs are laid in groups of 20-30 near fruit. Small larvae feed on leaves for a short time and then attack fruit. Feeding damage to fruit consists of 1/8 – 1/4 inch wide holes.
Management. Leaves must be inspected in June so that these pests can be found when small and before they feed on fruit. Growers should watch for each pest in their eggplants each year, because their populations will fluctuate greatly from year to year and field to field. If damaging populations are found and larvae are small Bt or XenTari can be used effectively. If larvae are larger then reduced risk pesticides such as Confirm, Avaunt, and SpinTor can be used. Other pesticides that will work are bifenthrin, Warrior, and Lannate.
Aphids. There are many different species of aphids that could be found in an eggplant field. Aphids are small, soft-bodied insects that vary in color from pale yellow to red to green to black, depending on the species (with one species capable of having several colors), the host plant, and time of season. Direct-feeding damage by aphids is rarely severe enough to kill plants. They pierce plant tissue with needlelike mouthparts, which may result in blossom shed or curling or stunting of new growth. They also produce a sticky material called honeydew that supports growth of a black sooty mold fungus, if the honey dew gets on the fruit it is difficult to remove making the fruit unmarketable. Three species of aphids can be found on eggplant in Maryland, the melon, potato and green peach aphids. The green peach aphid (Myzus persicae) is pale yellow to green with cornicles (long, slender tailpipe-like appendages) that are light in color and much shorter than in the potato aphid. Melon aphids (Aphis gossypii) are pear-shaped and vary from yellow to dark green, but have dark colored cornicles (red arrow). Potato aphids (Macrosiphum euphorbiae) are soft-bodied, tear-shaped insects that may be solid pink, a green-pink mottle or a light green with a dark stripe. Usually wingless, they are about 1/8 inch long. Adult females give birth to live young, called nymphs. Although slightly smaller than adults, nymphs are similar in color and shape.
Management. Aphids usually are not an important pest in eggplant unless too many pesticide applications have been made. Pyrethroid and carbaryl insecticides if used too often can cause an outbreak of these pests. These pesticides are broad-spectrum and kill many beneficial insects. These beneficial insects or natural enemies, such as predators (lady beetles and their larvae, syrphid fly and lace wing larvae), and parasitic wasps keep aphid populations under control most of the time unless their populations are disrupted. If aphid populations do increase to damaging levels there are several reduced-risk pesticides available that will give excellent control: Actara, Assail, Fulfill, imidacloprid, Platinum and Movento. Coverage of the foliage (under-side of leaves) must be thorough in order for best control of aphids.
Eggplant Lacebug. (Gargaphia solani) is an occasional minor pest of eggplant in Maryland. Lacebugs are brown with transparent, lacelike veins in the wings and are about ¼ inch in length. Adults overwinter in plant debris. Eggs are black and glued in groups on the undersides of leaves. Nymphs hatch and feed on leaves. Nymphs and adults feed with a piercing-sucking mouthpart in groups on the underside of leaves; covering them with brown spots of excrement. The leaves become curled and turn pale. Damage is usually minimal, but sometimes can cause economic damage. They are not present every year and damage is usually negligible as they are easily controlled with the materials used for other insect pests. Reduced risk pesticides include: Entrust, SpinTor, Radiant, Venom, and other pesticides include: Malathion and Vydate.
Thrips (most being flower thrips Frankliniella spp) may infest peppers, including western (WFT) (Frankliniella occidentalis) and eastern (Frankliniella tritici) flower thrips, and tobacco thrips (Frankliniella fusca). Thrips are tiny (1/16 inch), slender insects that vary in color from yellow or orange (most common color) to dark brown or black. Thrips overwinter in plant debris or on weeds such as winter annuals found in or around fields. In the spring they fly to plants producing flowers where they feed on pollen and nectar. They prefer to feed in flowers but also occur in flower and leaf buds and, occasionally, on leaves. There are two larval stages and a pupal stage. Thrips have only the left mandible and use this mouthpart to punch a hole or scrape the leaf or fruit surface of the plant disrupting cells and feeding on the cell contents. This feeding method damages eggplants in several ways; feeding in blossoms may cause blossom drop, or fruit may not develop properly and become deformed or scarred.
Management. to determine thrips presence; sample 20-40 flowers while scouting. Thrips will be visible inside the flower using a 10x hand lens, or the flower may be shaken over a piece of paper to dislodge the thrips for observation. The recommended thrips treatment threshold is ten thrips per flower. Reduced risk chemicals that will control thrips include: Assail, SpinTor, and Venom, with these other chemicals: pyrethroids, Renounce and Proaxis also working. DO NOT over apply chemicals for thrips control as this will increase the likelihood of resistance developing. Over application of pyrethroid insecticides favors the increase of western flower thrips.
Twospotted spider mites (TSSM) (Tetranychus urticae)are pests that very small, 1/80 – 1/60 inch long, with 2 spots on their back and are a problem usually in late July and August duringoverwinter in leaf debrisspring, mites feed on chickweed, clovers, andfind their way into fieldstheir feeding site and relfrom their abdomen that become airborne. Becauhost range, wherever they land they can usually start to feed. Females can lay 50-100 spherical eggs. Unfertilized eggs turn into males, and fertilized ones turn into females. The life cycle of the mites can be as short as 5-7 days in the summer. Mite infestations usually start on the field edge and move towards the center over time. Hot, dry weather conditions favor rapid development of eggs, increases feeding of nymphs and adults, and decreases the abundance of pathogenic fungi. Dusty conditions also favor mite activity. Both nymph and adult mites feed by piercing the cell walls of the leaf and sucking out the juices. Twospotted spider mites damage appears as a yellow discoloration or a mottled sand blasted appearance on tomato leaves, which can take on a bronze, then brown color.
Management. During hot, dry conditions that continue for several weeks fields should be checked closely, especially along borders and near grassy areas. The underside of several lower leaves should be checked for mite activity. A 10X hand lens can be used to identify mites. Leaves also can be shaken over a piece of paper, and the dislodged mites can be seen crawling around. If mites are found along the border of a field, the whole field should be checked for the presence of mites. An exact threshold for mites has not been developed. If there are only a few mites along the field borders with little mite activity in the interior of the field, then a treatment is not necessary, or just the border around the field may be treated. If there are mites found in scattered areas throughout the field and there is webbing found on the undersides of leaves, then a treatment will be necessary. Natural enemies help control and reduce mite populations under most circumstances and therefore, insecticide applications should be kept to a minimum. Natural enemies, however, can be overwhelmed by mite reproduction during hot, dry weather. There are two reduced risk chemicals available for mite control in eggplant: Acramite and Oberon. These other pesticides will also control two spotted spider mites: Vydate, Vendex and if populations are not large bifenthrin.
U.S. Department of Agriculture Flea beetles are just a tad larger than a pinhead and eat small holes in eggplant leaves.
I’m seeing small black bugs eating pinhole-sized holes through the leaves of my eggplant. How do I treat this problem?
A: That’s the work of flea beetles, the bane of eggplants. Flea beetles are tiny black bugs that chew holes in leaves like someone peppered them with miniature buckshot.
They’ll attack mustard, radishes and sometimes cole crops, but eggplant is their favorite. At least it is in my garden. The other telltale trait is that these little bugs hop off the plants when they’re disturbed, kind of like fleas. But these are not related at all to that hopping pest.
Floating row covers draped over the plants stop them, but then your garden looks like a bedroom with sheets laying around.
Some gardeners have had success setting yellow or white sticky cards or boards around target plants. When the beetles hop off or go for the color that mimics blossoms, they get stuck and die. I’ve made my own by spray-painting small boards yellow, strapping used plastic wrap over the board with rubber bands and coating the plastic with petroleum jelly or Tangle Trap (a gooey commercial bug-trapping product).
Although I haven’t tried it, some research says that using red plastic mulch under eggplants repels flea beetles.
Then there’s the spray option. A variety of chemical insecticides are labeled for flea beetles. Organic options are neem oil, garlic-based sprays, rotenone, pyrethrins and Pyola (a canola oil and pyrethrins combo from www.gardensalive.com.)
You might need to spray every week or so through August, when flea beetles taper off for the season. Flea beetles usually don’t kill eggplants, but they can mess up the leaves enough to seriously disrupt size and yield.
Natural Pest Control Methods
The Tasteful Garden promotes natural pest control methods such as keeping your garden clean and weeded, using mulches and good compost in the soil, and organically made pesticides only when absolutely necessary.
We believe that healthy, happy, plants will have a naturally immunity to pests and diseases and in the long run can protect our environment from overuse of pesticides. Visit our Organic Gardening department in our catalog.
In many cases, when you see damage to the leaves of a vegetable plant, the plant is not in danger of dying, only being nibbled on by an occasional insect. Other times, your plants can be literally eaten away overnight by some hungry snails, cut off at the base by a cutworm, or dug out of the ground by a squirrel. This can be heartbreaking when it happens but keep in mind that we share the earth with these creatures and your garden looks like a really great place to hang out! Most of the time, simple methods which have been used for many years by gardeners are the best way to combat the situation.
Below we have listed some of the more common pests for gardeners and the easiest technique to get rid of one or two, as well as a more thorough way to eliminate a full-on assault by these creatures.If you do use any type of commercially bought pesticides, always make sure to read the directions carefully and never use more than is recommended. Even organic pesticides can be dangerous and can kill honeybees and birds if overused. Killing every insect in your garden is not a good idea because many beneficial insects which eat other pests can be killed and this can create a worse problem. There are also many living creatures in the soil which help to break it down and provide nutritious soil for your plants which can be killed such as earthworms and bacteria.
Many diseases are spread by splashing water so water sprinklers and heavy rains can create molds, fungus’, and bacterial diseases which can make your plants very unhappy and sometimes can kill them. Mulching with dried leaves, pine straw, hay straw, grass clippings, newspaper, and even cardboard can make all the difference in keeping diseases under control. They can also help hold in moisture and protect from overheating the soil in the hot summer months. This keeps plants happier and healthier and can prevent stressful conditions which invite infestations of insects.
Organic gardening is done in the backyard by understanding that a healthy, happy plant, in good, nutritious, soil helps prevent most diseases and harmful insect damage. It is not necessary to kill every insect in the garden, as many pesticides do, but it is important to keep your garden mulched, watered, weeded and clean of debris to prevent problems.
The Tomato Hornworm is definitely the scariest pest in the garden, growing up to 5″ long, they resemble something from a bad 70’s movie. They are not dangerous to people but to a tomato plant they are very heavy feeders and can eat quite a lot of leaves. Female moths lay eggs under the leaves of the tomato plant and once they hatch and start feeding they grow quickly. They eventually make their way into the ground and stay until they become adult moths.
Roto-tilling in spring helps prevent worms and moving your tomatoes each year can also help. The best way to get rid of them once you know you have a problem is to look for them at dusk when they are most active. They can be very hard to find because of their coloring. They leave black droppings behind and that can help with tracking them down. Usually picking them off does the trick, just keep checking for new damage through the season. /p>
Many people use an organic product called Bacillus Thuringiensis, or BT Worm Killer Spray, which is a powder that you can spray on the underside of the leaves to kill the eggs. It washes off quickly in rain and must be applied once a week.
The Cabbage Worm and Parsley worms can cause a lot of damage to leafy green plants and their holes are often mistakenly blamed on some type of flying bug.
The Cabbage Moth, the pretty white butterfly we see in our gardens couldn’t possibly be causing any damage. Most of us think that a bug has to be ugly and black or green to be a “bad” bug. This butterfly can lay eggs on a plant and within a few days they are hatched and eating their weight in leaves every day. The eggs of the Cabbage Moth will be found underneath the leaves.
Butterflies for the Parsley worm are really beautiful and many people grow parsley for their ability to attract them to the garden. However, if you are growing parsley to eat the parsley, make sure you watch carefully for signs of the butterfly and either cover the plants up with row cover or spray BT to prevent these caterpillars from doing serious damage.
Watch carefully throughout the season for moths and as soon as you see them fluttering start looking for the eggs and worms. Picking off caterpillars usually keeps them under control, just keep checking for new damage throughout the season. Or, you can spray your plants organically, underneath the leaves, with Bacillus thuringiensis or “BT” to kill the hatching worms. BT can be washed off by rain so it must be applied about once a week. Larger caterpillars can be squashed if you prefer which is more fun.
Slugs & Snails
Slugs and Snails are not really bugs but they can be some of the worst creatures in your garden. They are leaf and stem eaters and there are certain plants they love to eat like Basil and leafy garden vegetables. They can even climb small citrus trees and eat the leaves and suck on the fruit. They can eat their way through a young basil plant literally overnight and leave you blaming the rabbits, squirrels or your dog. They eat all night long and hide in dark, cool, damp places all day long. There are several ways of preventing their damage and I will try to tell you which ones work and why.
The most commonly used prevention is the slug and snail baits that are sold in garden centers. They do work if you follow the directions on the box and replace them when it rains. They contain Metaldehyde and as the snails eat it they will slowly die. Many formulations can be dangerous to use around birds or pets and are not labeled for use around edible plants. Fortunately there has been a new bait developed called “Sluggo” that is safe around pets and will break down into iron in the soil. It is pricey but good and very safe for use around herbs and vegetables
The best way to prevent snails and slugs is to create barriers that they cannot cross over to get to your basil. Any type of copper can be used to make a wall that electrically shocks their body (fun isn’t it) or wood ashes, crushed egg shells (easy and cheap), or diatomaceous earth which cut into their soft flesh.
Another thing that needs to be done is to try to eliminate as many of the snails as you can find. You don’t have to go out into the garden at night with a flashlight. You can place boards out in the area propped up slightly and they will hide there during the day. Go out in the afternoon and remove them from the shady side of the board and destroy them. Follow their slime trails to track down their hiding places. Beer traps work by drowning slugs but hardly ever catch snails as they are not really beer drinkers.
Encourage natural enemies such as birds, toads, and salamanders, also chickens and ducks are efficient snail hunters. Good luck and don’t have too much fun
Mexican Bean Beetle
The Mexican Bean Beetle and the Japanese Beetle attack most varieties of Bean plants as well as roses and many other plants, eating away at the leaves until they look similar to lace.They can be very destructive to bean plants and their pods. They should be watched for during June through August when the adults are most actively feeding. They start out yellow or beige and develop their spots after reaching full adulthood. Check your plants frequently under the leaves for egg sacks and remove them immediately.
If the damage is visible, lay a cloth under the plants and shake the stems until the beetles fall off the plant. Collect them on the cloth and dispose of them. The best pre-treatment for Japanese beetles is Milky Spore which is a bacterial powder that kills only Japanese beetle grubs while they are feeding underground in the Fall. There are also organic sprays that can be used in cases of severe infestation. Always use all pesticides, even organic ones, as directed on the bottle.
Whiteflies & Aphids
Whiteflies and Aphids are a nuisance more than damaging but if left alone, can create a colony very quickly which can cause a lot of damage. Whiteflies are small flying bugs which when disturbed will fly up and around the plant in a frenzy for a few seconds. Aphids are small non-flying bugs which can vary in color depending upon what they are eating. They do not have teeth and if you see holes in the leaves, don’t blame these insects. Their damage is to the soft, tender, new growth and they suck the sweet juices out of the leaves.
Aphids and Whiteflies will usually attack plants that are under stress of some kind. Indoors, herbs are always under some kind of stress, usually one of three things is the case. The first is not enough light (they need about 4 hours a day), second could be that their pots are too small for them (6″ should be the absolute minimum size), third is too much watering (never let your plants sit in a tray of water and don’t water until the soil feels dry to the touch). If you find that one or more of these is the problem, do what you can to correct it first before you spray. If that does not get rid of them, you can spray them with a little soapy water (dish washing soap squirted into a spray bottle filled with water) or insecticidal soap such as this Earth-tone product. Leave it on for only a hour or so and then wash it off. You may need a couple of treatments but it will get rid of them eventually.
There is also an organic spray that is called Neem II t that is even better than the soap spray. It is made from Neem oil and is combined with Pyrethrum from the Chrysanthemum plant, which works on many types of insects as a deterrent and a killing spray. Spinosad (or Lawn and Garden spray) is also available as a quick knock down for aphids and is very effective.
Squash Vine Borer
The squash vine borer is a key pest of squash, gourds and pumpkins. Unfortunately, it is usually noticed only after it has done its damage. Symptoms appear in mid summer when a long runner or an entire plant wilts suddenly. Infested vines usually die beyond the point of attack.
Sawdust like frass near the base of the plant is the best evidence of squash vine borer activity. Careful examination will uncover yellow brown excrement pushed out through holes in the side of the stem at the point of wilting. If the stem is split open, one to several borers are usually present. The caterpillars reach a length of 1 inch and have a brown head and a cream colored body.
The adult squash vine borer is a stout dark gray moth with ‘hairy’ red hind legs, opaque front wings, and clear hind wings with dark veins. Unlike most moths, they fly about the plants during the daytime, appearing more like a paper wasp than a moth.
This insect overwinters as a full grown larva or a pupa one to two inches below the soil surface. If it has not already done so, the larva pupates in the spring. Adult moths begin to emerge about the time the plants begin to run, and moth flight continues through mid August.
The small brown eggs, laid individually on leaf stalks and vines, hatch in seven to 10 days. The newly hatched larva immediately bores into the stem. A larva feeds for 14 to 30 days before exiting the stem to pupate in the soil. There are sometimes 1 to 2 generations per year.
Home gardeners may have some success with deworming the vines. At the first signs of the sawdust like frass, vines are slit lengthwise near where the damage is found and the borers removed. The stems should be immediately covered with earth. Sanitation is also important. After harvest is complete, vines should be removed from the garden and composted to prevent the remaining borers from completing larval development. Burying a few nodes along each vine will encourage rooting at these nodes. This will lessen the impact if squash vine borers girdle the base of the vine. Visit our Organic Gardening department in our catalog for more great products.
Honey Bees & Bumble Bees
Honey Bees and Bumble Bees are the primary pollinators of vegetables, fruit trees and flowers. They are very important creatures in the garden. The native bumblebee is a large, black, fuzzy bee with a yellow or reddish stripe on its middle. It is the bee that pollinates your tomatoes, peppers and eggplants. Along with Honeybees and Orchard Mason bees, they feed on pollen and nectar from the flowers of garden plants and flowering trees. As they go from flower to flower they distribute the pollen and this creates the process which results in fruiting. Without their help the plants are on their own and cannot propagate by themselves.
Pesticides can be very toxic to bees, especially Carbaryl or Sevin dust which is a particularly strong insecticide that may cause cancer. Many bee viruses and certain species of mites, in addition to spraying of pesticides, have killed off large numbers of naturalized honeybees. It is important to create areas in our gardens which allow them to multiply. Plant nectar flowers and flowering lavenders near your vegetable gardens and provide a source of water for them and they will thrive. Never spray any pesticides which are harmful to bees and use organic sprays which evaporate quickly. Watch out for nests and hives so you don’t get stung because once they have used their stingers, they will die.
Ladybugs (Lady Beetles)
Ladybugs (Lady beetles) are a great pleasure to see in your garden because they are so indispensable for fighting aphid problems. It is technically a beetle and grows to about 1/4 inch long. Ladybugs cause no plant damage at all and are sold in garden centers everywhere. They will eat large amounts of aphids and then fly onto another plant to eat more.
Be aware that if you buy a box of ladybugs they may move on to your neighbors house when they can’t find enough to eat at your house. It is a good idea to spray your plants with a diluted sugar-water solution before you release them to give them a drink and make them want to stay home. Many household pesticides (even insecticidal soaps) can kill ladybugs and their larvae so always spray carefully, even if you use organic methods.
Click to read more about these insects
Slugs and Snails
Mexican Bean Beetles
Squash Vine Borers
Click to read more about these insects
बैंगन के कीट पतंग तथा प्रबंधन कैसे करें।
Brinjal is one of the important solanaceous vegetable cultivated in arid region of Rajasthan. The crop is grown during the monsoon period where the supplement irrigation is available. In addition to abiotic stresses, the major challenge ahead brinjal cultivation is insect pests especially shoot and fruit borer, a devasting pest of brinjal In India. Often, farmers are going up to 10-30 spray per season to save the crop.
Over use of synthetic pesticides increase the cost of production at farmer level and increase the environmental and health hazards at consumer level. In this context, it is essential to step up towards IPM as it is more reliable and eco-friendly than any other methods. Here we have given some of IPM oriented strategies which will be highly useful to growers of this region to manage these pests successfully.
1. Shoot and fruit borer, Leucinodes orbonalis (Pyraustidae: Lepidoptera)
Most serious pest of brinjal and causes yield loss up to 60-70%.
The infestation starts during early stage of the crop and continues throughout the fruiting stage. Initially the larvae attacks the shoots result in drooping of shoots and dead heart. Later stages, the larvae starts to feed on flower buds and fruits but it prefer more on fruits, the infestation during fruit set causes shedding of buds. Larvae bore the fruits and holes are sealed with excreta and make them unfit for consumption.
Biology of fruit borer in brinjal
The adult moths are white in colour with brownish red marking on the fore wing. And it lays an average of 250 eggs singly on the tender shoots, flowers and developing buds. Larvae are pinkish in colour and fully developed with prominent head capsule with sparse hairs on their body. Pest is active throughout the year but more during monsoon. The pupation takes place in the plant debris with brownish cocoon. The egg, larval and pupal period is 3-5, 15 and 7 days and it varies with season.
Shoot Borer damage on Brinjal Larvae inside of shoo
Damaged fruit Larvae inside the fruit
Management shoot borer in Brinjal
- Early removal of drooping shoots will reduce the fruit infestation.
- Proper collection of all the infested flower buds, fruits during harvest.
- Continuous cultivation of brinjal also favours the pest infestation.
- Varieties like Punjab Barsati, (moderate resistant cultivar) Pusa purple round, Punjab Neelam found to be resistant to brinjal fruit borer.
- Biological method recommended by IIHR, Bengaluru involving release of Trichogramma chilonis @10 to 15 lakh parasites/ha/season along with 2 sprays of Bt formulation found to be economically effective.
- Installation of BSFB pheromone traps to monitor and mass trap the male moths.
- Need based application of carbaryl 0.1% and profenofos 0.05% or spray of cypermethrin (0.0125%) at 2% flower buds damage threshold or at 15-20 days after flowering.
2. Hadda beetle, Henosepilachna vigintioctopuntata (Coccinellidae: Coleoptera)
It is one of the important pests of brinjal often it causes serious damage to leaf. Both grub and adult are causing the damage. It feeds the epidermal layer of leaves result in complete dry of leaves.
Hadda beetle damage on Leaves Adult beetle Grub
Biology of Hadda Beetle
The adult beetle is brownish yellow with block colour spot (12-20) on the elytra and they are hemispherical in shape. Eggs are spindle or cigar shaped and bright yellow in colour and lay in clusters (10-20) on lower surface of the leaf in a group and grubs are spiny. Egg stage lasted in 3-4 days and grubs stage is 10-35 days. Pupation takes place within the leaf or stem and duration is 7 days. The total life cycle is about 17-50 days depending on the climate.
Management of Hadda beetle in Brinjal
- The separate management practices are not needed; the control measures taken for fruit borer are enough.
- Collection and destruction of grubs and adults at the early stage of infestation will reduce the further infestation
- Spray of contact insecticide like carbaryl (0.1%) or quinalphos (0.05%) when the incidence is severe.
- Need based application also will help to build up the larval-pupal Eulophid parasitoid Pediobius foveolatus which is found to be associated with this pest and cause significant mortality under natural condition.
3. Jassids, Empoasca devastans (Cicadellidae: Homoptera)
It is a ployphagous pest causing serious damage by sucking the leaf sap. The nymphs and adults suck the sap from under surface of the leaf and infested leaves curl upward in margins. While feeding it also inject the saliva and sever causes the leaves are crinkled with stunted growth. Brownish reddish colour at the leaf margin called as ‘hopper burn’ symptom.
Biology of Jassids
Adults are green colour slender insect and nymphs are different in colour with wedge shaped body. The younger leaves are more preferred for egg laying and they are laid singly inside of leaf veins on under side of the leaf. Activity of the pest can be observed throughout the season. The total life cycle is about 10-21 days.
Management of Jassids in Brinjal
- The varieties such as Kalyanpur, Punjab chamikila, GB-1, and GB-6 reported as resistant to Jassids, Aphids and Whitefly.
- Avoid over use of nitrogenous fertilizer and follow recommended spacing.
- Use yellow sticky traps to monitor the sucking pest activity.
- Application 5% dimethoate granule along seed furrows or spray of imidacloprid 25g a.i/ha will give better control.
Other important Sucking Pests
White fly, Bamisia tabaci and Aphid, Aphis gossypii also cause damages by sucking the sap from tender leaves leads to crinkling and yellowing of leaves. The infestation reduces the plant growth and vigour.
4. Root knot nematode, Meloidogyne incognita
The nematode damage is more detrimental to the seedling than the mature plant. The affected plant show stunted growth along with chlorotic symptom on the leaf and drastically affect the fruit setting. The numerous galls can be observed on the root of the plant when it is up rooted.
- Trap cropping marigold Tagetus sp are effective in controlling Melidogyne incognita.
- Crop rotation with non solaneceous crops.
- Treat the nursery beds with Carbofuran 2g a.i/m2 granules will give better control.
V. Karuppaiah1, S.K. Maheshwari1 and Hanif Khan2
1Central Institute for Arid Horticulture, Beechwal, Bikaner, Rajasthan-334006
2Regional Station, Directorate of Wheat Research, Flowerdale, Shimla (HP)