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Plant NameTypeDescription 
Curly top (Western yellow blight)Pepper, EggplantDiseaseCurly top is caused by a virus transmitted by the beet leafhopper. Many crops are affected, including tomato, bean, squash, cucumber, and pepper. Typical symptoms of the disease include puckering and downward curling of leaves, followed by a general yellowing of the plant and death of young plants. Older plants are yellowed and dwarfed. Leaves are thicker than normal and brittle in texture. The virus is also found in annual flowers and weeds.
Mosaic virusesPepper, EggplantDiseaseSeveral viruses can cause mosaic symptoms in peppers. Most of these viruses are transmitted by aphids, but Tobacco Mosaic Virus is also transmitted by mechanical means including tools and hands. Tomato Spotted Wilt Virus is transmitted by thrips. Typical mosaic symptoms include development of yellow to green leaf mottling, ringspot or line patterns on leaves or fruit, curling and distortion of leaves, and stunted plants. Fruit infected with Tobacco Mosaic Virus is yellow or mottled and is often also deformed and dwarfed. Mosaic viruses typically survive through the winter on perennial hosts including alfalfa, clovers, and weed species.
Physiological leaf rollPepper, EggplantDiseasePhysiological leaf roll of pepper and eggplant is a cultural problem associated with drought, high soil moisture, or high temperatures. The leaves of the plants roll downward and become leathery or brittle in texture. Symptoms may resemble those caused by virus diseases, but plants remain green and are not stunted or deformed. Growth is not usually affected. This is a common problem that causes no damage to the plants and does not seem to affect yield.
Verticillium wiltPepper, EggplantDiseaseVerticillium wilt is caused by a fungus commonly found in the soil. Many species of plants can be affected. Potato and tomato are favored hosts. Infected peppers and eggplants are stunted and have yellow leaves which tend to roll inward. Eggplants first show yellowing of the lower leaves in conjunction with stunting of plants and discoloration of the vascular system (noticeable when cuts are made into stems). Typically, the fungus attacks the roots and moves throughout the plant via the vascular system. Verticillium is also carried in infected eggplant seed.
Brown marmorated stink bugPepper, EggplantInsectThe brown marmorated stink bug (BMSB) is an introduced pest species from Asia that is spreading quickly across the United States. Nymphs and adults feed on a wide variety of plant hosts. BMSB prefers to feed on fruit, seeds, and seed pods, but will also feed on stems and leaves of some hosts. Both adults and nymphs have piercing-sucking mouthparts and inject digestive enzymes into plant tissues to aid in feeding. On pepper, BMSB damage appears initially as a slightly sunken, light-colored or “cloudy” spot on the surface of the fruit. These injured areas may decay as the fruit matures, or the fruits may become distorted, catfaced or fail to develop. At the feeding site, whitish corky or spongy areas develop under the skin and secondary damage from rot may occur. Other known vegetable hosts of BMSB include tomatoes, corn, beans, and cucumbers. One or two generations of BMSB per year are expected in the Pacific Northwest. Adults overwinter in sheltered locations (including houses, where they can become a significant nuisance pest). In the spring, light green to white eggs are laid in groups of about 20 to 30 on the underside of leaves. Young stink bugs, or nymphs, are black with a red-and-black striped abdomen. Nymphs often feed in groups when young. Older nymphs are dark with white bands on body, legs, and antennae. They may feed in groups or singly. Adults are a little over 1/2 inch long, with a shield-shaped body. Body color on adults is mottled gray and brown, while the legs and antennae have alternating dark and light bands. The abdomen also has dark and light bands which are visible at the edge of the wings. NOTE: BMSB adults closely resemble other stink bugs found in WA and OR. For more information on BMSB identification, see FS079E, Pest Watch: Brown Marmorated Stink Bug, available at
Flea beetlesPepper, EggplantInsectFlea beetles are small, brown to metallic black beetles with a habit of jumping like fleas when disturbed. They feed on many plants including beets, kale, collards, radish, and many weeds, particularly those in the mustard family. Small round holes are eaten in the leaves, usually early in the season. The larvae typically feed on underground portions of the host plants. Damage can be very severe on seedling plants.
WhiteflyPepper, EggplantInsectWhiteflies are common pests in the greenhouse and garden. The adult whitefly is a tiny (1/10" or less), white, moth-like insect. They typically feed on the underside of leaves, flying up in clouds when disturbed. The immature whiteflies (nymphs) are also found on the underside of leaves, and are oval, flat, and variously-colored. Whiteflies feed by sucking sap from plant tissues. Damaged leaves wilt, turn yellow or brown, and may drop. Plants may be stunted by severe infestations. Whiteflies also produce honeydew, a sweet, sticky material which may attract ants or become covered with growth of dark sooty mold.