Estimates of combining ability for development of F₁ hybrids in cucumber

Eleven lines of parthenocarpic and gynoecious cucumbers were crossed with three monoecious testers in line × tester design producing 33 F1 hybrid seeds. Hybrids were then grown in randomized block design in two environmental conditions (E1, March-June; E2, August-December) under polyhouse. Fifteen economically important characters were observed from five plants selected at random. The best promising general combiner and tester were PCUCP-4 and PCUC-8, respectively with significant general combining ability for yield contributing characters, which could be used for accumulation of favourable genes in breeding programmes. Different environmental conditions inside polyhouse influence the performance of cross combinations. Parthenocarpic along with monoecious genotypes produce more stable cross combinations than gynoecious with monoecious types inside polyhouse. The best cross combinations based on specific combining ability effects for fruit yield per plant were PCUCP-3 × PCUC-8 and PCUCP-3 × PCUC-25 in E1 and E2, respectively. In both the environments, PCUCP-4 × PCUC-8, PCUCP-3 × PCUC-8 and PCUCP-7 × PCUC-25 cross combinations were found to be the most stable for maximum characters and could be used for hybrid cucumber production under polyhouse conditions.