Botrytis leaf blight (BLB) is a fungal disease that occurs in many of the onion growing areas of the world. The causal organism, Botrytis squamosa, causes leaf spots (lesions) and maceration of leaf tissue resulting in leaf dieback and blighting....

Potatoes are a vegetatively propagated crop, and many disease organisms including several viruses and a viroid are disseminated in tubers. The important role that tubers play in virus spread is recognized by the strict requirements for foundation...

Tomato anthracnose is a serious disease of processing tomatoes caused by the fungus Colletotrichum coccodes and is a threat to tomatoes grown in New York State. To minimize the mold count in processed tomato products, processors impose a strict...

, such as central and western New York State, epidemics of the disease may develop. Production is reduced because of poor seed germination, poor seedling vigor, and low yields. Marketing losses are attributed to seed spots and blemishes, which lower their quality...

Rhizoctonia solani is a fungus that attacks tubers, underground stems, and stolons of potato plants. Although it probably occurs wherever potatoes are grown, it causes economically significant damage only in cool, wet soils. In temperate production...

, and the production of unmarketable fruit. Early recognition of the disease, especially in greenhouse crops, is essential if the disease is to be contained. The organism is seedborne and can survive for short periods in soil, greenhouse structures, and equipment...
organism into transplant production fields in southern Georgia originated on commercial seed. If seeds are harvested by either the acetic acid extraction method or by the fermentation process, the threat of seedborne inoculum is greatly reduced...

Viruses are the most common causes of diseases affecting cucurbits in New York. These diseases result in losses through reduction in growth and yield and are responsible for distortion and mottling of fruit , making the product unmarketable. A...

-causing organism, it is responsible for crop loss in a wide variety of unrelated crops. Botrytis bunch rot is especially severe in grape cultivars with tight, closely packed clusters of fruit. Botrytis is also responsible for storage losses of grapes picked...

organisms. Epidemiology and disease development The following comments address pepper Phytophthora blight (P. capsict), and in general also apply for diseases of crops listed in the table. The fungus occurs naturally in most soils and can infect Fig. 5...
(two-tailed) motile zoospores. These spores produce germ tubes that penetrate plant tissue. The cycle is repeated with the production of more sporangiophores and sporangia. When the humidity is high, the sporangia can survive for long periods. During...

as disease appears, using a fixed copper plus maneb 80 WP or maneb plus zinc product to prevent secondary spread of the bacterium. The combination of copper and maneb has been shown to be more effective in controlling strains of the organism that are either...
of lesions can occur on leaf margins and tips where moisture accumulates (fig . 1). Eventually the leaves yellow and drop off, increasing the chance for sunscald (fig. 2). Spots on fruits become raised, scablike areas that make the product unmarketable (fig...