Plant Disease Phenotype

Affecting a wide variety of horticultural and vegetable crops — roses, beans, tobacco, tomatoes, potatoes, cucumbers and peppers — mosaic is a viral diseases found throughout the United States. Plant viruses can be difficult to detect as symptoms look similar to many nutrient deficiencies and vary depending on the age of the plant when infection occurs. Look for: Yellow, white or green stripes/ streaks/ spots on foliage Wrinkled, curled or small leaves Pronounced yellowing only of veins Stunted growth and reduced yields Infected fruit appears mottled and develops raised “warty” areas Mosaic virus overwinters on perennial weeds and is spread by insects that feed on them. Aphids, leafhoppers, whiteflies and cucumber beetles are common  garden pests  that can transmit this disease. Soil, seed, starter pots and containers can be infected and pass the virus to the plant. Cuttings or divisions from infected plants will also carry the virus. Treatment There are no cures for viral diseases suc

Commonly found throughout the United States, Fusarium wilt is a soil-borne pathogen that attacks potato, tomato, eggplant and pepper plants. Disease fungi ( Fusarium oxysporum ) enter through the roots and interfere with the water conducting vessels of the plant. As the infection spreads up into the stems and leaves it restricts water flow causing the foliage to wilt and turn yellow. Disease symptoms often appear later in the growing season and are first noticed on the lower (older) leaves. As the disease progresses, the younger leaves will also be affected and the plant eventually dies. In many cases, only one branch or side of the plant show symptoms. Fusarium wilt can survive for years in the soil and is spread by water, insects and garden equipment. The fungal disease develops during hot weather and is most destructive when soil temperatures approach 80˚F. Dry weather and low soil moisture encourage this plant disease. Treatment Plant resistant varieties when available. Remove stri

A fungal disease that affects peaches and nectarines, leaf curl ( Taphrina deformans ) is one of the most common disease problems found in backyard orchards. Symptoms appears in spring as reddish areas on developing leaves. These areas become thick and puckered causing leaves to curl and distort. When severe, leaf curl can substantially reduce fruit production. Disease fungi overwinter as spores (conidia) underneath bark, around buds and in other protected areas. Early in the growing season, during cool, wet spring weather, the spores infect new leaves as they emerge from the buds. Later, the fungus produces great numbers of new spores which are splashed or blown from tree to tree. Leaf curl is most active at temperatures between 50-70˚F, but can occur at relatively low temperatures. In fact, cool weather is thought to extend the infection period because new leaves are growing slowly. Wet weather is necessary for infection. Treatment Select resistant varieties whenever possible. Leaf c