Resistance to gummy stem blight (Didymeh bryoniue) was not detected among 1208 cucumber lines of diverse origin when cotyledons of four-day-old seedlings were inoculated with an aqueous suspension of 5000 spores of D. bryoniue delivered to freshly crushed tissue, followed by 48 h incubation at 20°C and 100% RH in the dark. Among 49 lots evaluated for gummy stem blight in the field, cv. Homegreen #2 and PI 200818 from Burma were resistant. Earliness in fruit maturity was positively correlated with susceptibility to gummy stem blight (r = 0.424). Cucumber accessions differed in the incidence ofstem and hypocotyl cankers. In greenhouse grown plants at the 2nd-3rd leaf stage, differentiation of resistant lines was obtained by spraying plants with an aqueous suspension of 106/ml D. bryoniue spores followed by 48 h incubation at 20°C and 100% RH in the dark. One cycle of mass selection in Homegreen #2 resulted in improved gummy stem blight resistance. 603 A. I. WYSZOGRODZKA,

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