Effects of Stage of Harvest and Post-harvest Ripening of Fruits on Seed Yield and Quality in Cucumber Grown under Open Field and Protected Environments

Abstract

Among the various stages of fruit harvest 35, 40, 45 DFP under open field (E1); and 45, 50, 55 DFP under protected (E2) environments, in combination with post-harvest ripening (PHR) periods (0, 10, 20 and 30-days);treatment F2P4 (40 DFP+30-days PHR), followed by F3P3 (45 DFP+20-days PHR) under open field, whereas, treatment C2P4 (50 DFP+30- days PHR), followed by C3P3 (55 DFP+20-days PHR) under protected environment, were superior in optimizing both seed yield and quality in two cucumber varieties (Pusa Barkha and Pusa Uday), during 2019-20, at ICAR-IARI, New Delhi. The seed yield attributes (i.e total filled seed and 1000-seed weight) and seed quality attributes (germination and vigour) were higher under protected environment. Maximum seed fresh & dry weights, and minimum seed moisture content, EC, TSS and TSP (from seed leachates) were registered with treatments F3P3 under E1, and C3P3 under E2. Of the seed composition, total soluble proteins, starch and oil contents (in seed) increased with the progression of seed maturation and PHR period (0 to 30-days), whereas total soluble sugars (in seed) significantly reduced, may be due to its conversion into starch. Reduced ROS (O2 ·- and H2O2) in PHR seeds (from all stages of seed development), may be due to reduction in seed moisture, which imposes a lower potential threat to seed, consequently reduced antioxidants(SOD, CAT and POX); indicative of physical and physiological soundness of seeds.