Effect of application of paclobutrazol on growth and yield of salad cucumber cultivated in protected house.

Abstract

Cucumber, variety CU13502 (Cucumis sativus L.) belongs to the family Cucurbitaceae that are popular in summer dishes and salads around the world. The objective of the study is to determine how paclabutrazole (PBZ) affects the growth and yield of salad cucumbers by developing shorter plants. Cucumber grown in 100% coir media, with foliar application and substrate application of PBZ following two factor factorial Completely Randomized Design (CRD) with three replicates. The two different methods of applying paclabutrazole to plants are as a substrate and a foliar spray. The treatments were, T1-500 ppm, T2-250 ppm, T3-125 ppm, T4 -62.5 ppm and T5 - 0 ppm /control. The treatments were applied at a 14 days’ interval while vegetative and yield data were recorded. Data were statistically analyzed using analysis of variance (ANOVA). The means separation was performed using Duncan’s multiple range test (DMRT) at 5% probability level. The results revealed that there was significant interaction between method of application and concentration of PBZ on vegetative and yield parameters of salad cucumber. The significantly lower internodal length was recorded in 500 ppm (30.23 mm), 250 ppm (33.75 mm) and 125 ppm (34.27 mm) of substrate application of PBZ. Further, higher internodal length was recorded in 0 ppm/control (86.64 mm) of substrate application and followed by 0 ppm/control (75.76 mm) of foliar application of PBZ. The significantly higher leaf length was recorded in all concentration of foliar applications of PBZ and 0 ppm/control (231.55 mm) and 62.5 ppm (165.88 mm) of substrate application of PBZ. When considering the average fruit weight, 62.5 ppm (190.34 g) of foliar application and 0 ppm/control (174.49 g) of substrate application of PBZ had shown the higher average fruit weight. Furthermore, the highest total yield was shown in 0 ppm/control (4502.07 g) of substrate application of PBZ and 62.5 ppm (3927.45 g) of foliar application of PBZ. Research findings can be concluded that foliar application PBZ in 62.5 ppm with 14 days’ interval (from 15 days after seed sowing, until end of harvesting) reduce the vegetative growth while increasing the yield of salad cucumber.