Cucumber Green Mottle Mosaic Virus, its Effect on Yield and its Control in the Lea Valley, England.

Cucumber green mottle mosaic virus was very widespread in cucumber crops in the Lea Valley in 1964. Experiments on the effect of this virus on yield indicated that losses of approximately 15 per cent occurred with early infection. Later infection had little effect on yield. Dry heat treatment of infected cucumber seeds at 70°C for more than one day was sufficient to inactivate the virus and these results were also confirmed using virus-impregnated filter paper squares. Cucumber seeds were found to tolerate dry heat treatment at temperatures of 75°C and 80°C with little adverse effect but, at 80°C, germination was delayed and the cotyledon leaves were distorted. In a commercial trial, over 45,000 cucumber plants free from symptoms of the virus were raised from infected seeds which had previously been heat treated at 70°C for three days. [ABSTRACT FROM AUTHOR]