Evaluation of melons and indigenous Cucumis spp. genotypes for drought tolerance.

Abstract

Climate change affects the performance of many crop plants worldwide. Abiotic stress such as moisture stress is one of the important factors, reducing average yield of major vegetable crops by more than 50%. The present study was planned to find out simple and precise field techniques to detect moisture stress tolerant genotypes of melons and Cucumis spp. A total of 121 genotypes of melons and Cucumis spp. including 43 lines of Cucumis callosus, 19 lines of Cucumis melo, 29 lines of Cucumis sativus, 27 lines of Cucumis melo var. momordica, 2 lines of Cucumis melo var. utilissimus and 1 line of Cucumis melo var. chate, were planted in two sets during the summer season of 2010, at IIVR, Varanasi, in a randomised block design with two replications. Both sets were kept under regular irrigation and normal agricultural practices were applied during the initial 30 days. After 30 days, irrigation in one set was withdrawn. Irrigation, however, continued with the other set as per requirement and observations were recorded. The treatment set which was exposed to moisture stress, was re-irrigated after one month of stress exposure. During the period of water withdrawal accessions were evaluated using a five point scale (1-5) and seven horticultural parameters, which included fruit count/plant, fruit weight, yield/plant (g), yield/ha (q), fruit length (cm), fruit width (cm) and vine length (cm) in both sets of experiment. The drought tolerance efficiency (DTE) was calculated using both sets of data. Based on the observations above, 5 genotypes, which include 2 lines Cucumis callosus (SKY/DR/RS-101 and AHK-200), 1 line each of Cucumis melo (SC-15), Cucumis melo var. momordica (VRSM-58) and Cucumis melo var. chate (arya), were identified as drought tolerance genotypes based on DTE % and yield parameters. These lines of melons and Cucumis spp. should be included in long term breeding programs because they have high moisture stress tolerance efficiency.