First report of squash silverleaf disorder in New York State
Symptoms of squash silverleaf have been observed for the first time in Northeastern United States, on Cucurbita pepo (cultivated in the field but transplanted from the greenhouse) during August 1993 at the Long Island Horticultural Research Laboratory, New York (US). Whitefly populations associated with this disorder were identified as Bemisia argentifolii (Bemisia tabaci biotype B - EPPO A2 quarantine pest). The authors concluded that although B. argentifolii and associated disorders have become a major limitation to vegetable production in Florida, Arizona, California and other southern states, this may not occur in northern states where the pest cannot overwinter outdoors. They felt that the unusually hot and dry conditions of the 1993 growing season, which were very favourable to the insect development, may have contributed to this outbreak.
Sources
McGrath, M.T.; Gilrein, D.; Brown, J.K. (1994) First report of squash silverleaf disorder associated with B-biotype sweetpotato whitefly in New York.
Plant Disease, 78 (6), p 641.