Effect of Plant Growth Regulator on Growth, Yield, Quality and Economic of Summer Squash (Cucurbita pepo L. Var. Pattypan) in Mid Hills of Uttarakhand

Field study on the Effect of Plant Growth Regulator on Growth and Yield of Summer Squash (Cucurbita pepo L. Var. Pattypan) was conducted during 2017 (summer season). Ten treatments of plant growth regulator consist of T1 Control; T2 Ethrel 150 ppm; T3 Ethrel 200 ppm; T4 Ethrel @ 250 ppm; T5 Gibberellic acid (GA3) @ 25 ppm; T6 Gibberellic acid (GA3) @ 50 ppm; T7 Gibberellic acid (GA3) @ 75 ppm; T8 Naphthalene acetic acid (NAA) @ 50 ppm; T9 Naphthalene acetic acid (NAA) @ 100 ppm; T10 Naphthalene acetic acid (NAA) @ 150 ppm were tried in Randomized Complete Block Design having three replications. Results revealed that the maximum number of male flowers per plant (13.63) was found under T5 that was closely followed by T4, T7, T3 and the lowest number of male flowers per plant (7.06) in T9. In contrast, the maximum number of female flowers per plant (7.86) was found under T9 while the lowest number of female flowers per plant (4.76) was found under T7.The lowest sex ratio (1.26) was observed with T9, while the highest sex ratio (2.43) was observed with T6.The maximum fruit set percent (71.58) were found under T8 that was statistically identical by T10: Naphthalene acetic acid 150 ppm while the minimum fruit set (49.02) were found under T2. Different plant growth regulators showed a statistically significant variation on number of fruits per plant. The maximum (6.03) fruits per plant in number were recorded under T9 and the minimum fruits per plant were recorded in T2. The yield of summer squash was recorded the maximum (403.75 q ha-1) in treatment T4 which was closely followed by T10. The quality parameters i.e., TSS (4.66) and shelf life (114.6 days) of summer squash was determined the maximum in T8 as compared to other treatments. The economics of using different growth regulators revealed that the benefit cost ratio was the maximum with Naphthalene acetic acid (NAA) @ 100 ppm (T9) followed by Ethrel 250 ppm (T4). The overall results showed that the effective treatment for increasing femaleness and yield of Summer Squash was Ethrel (250 ppm) with the satisfactory benefit cost ratio (4.23).