INFLUENCE OF PLANT GROWING STRUCTURES AND DIFFERENT COMBINATIONS OF GIBBERELLIC ACID AND SILICON ON SUMMER TOMATO IN ROOFTOP GARDEN

Abstract

An experiment was conducted in the rooftop garden of Agricultural Botany Department, Sher-e-Bangla Agricultural University, Dhaka during June to October 2016 to assess the influence of different plant growing structures and different combinations of gibberellic acid (GA) and silicon (Si) on summer tomato cultivation for spreading the sustainable urban agriculture in the Dhaka city. GA3 and Silicic acid (SA) were used as source of GA and Si, respectively. Summer hybrid tomato Success, Bejo Sheetol Seed Company (BD) Limited was used in this study. The two factors experiment was laid out in Randomized Complete Block Design (RCBD) with four replications. Factor A was different kinds of plant growing structures which includes three types; earthen pot (E), concrete bed (C) and wooden bed (W) and Factor B was four different combinations of GA and Si; H0= 0 ppm GA3 and 0 mM Si, G=20 ppm GA3 and 0 mM Si, Si=0 ppm GA3 and 0.4 mM Si, GSi= 20 ppm GA3 and 0.4 mM Si. The total treatment combinations were 12 (3 x 4). The experimental results showed that plant growing structures significantly influenced to change morpho-physiology, yield contributing characters and fruit yield of summer tomato. The morpho-physiological characters including plant height, number of leaves and branches plant-1, stem diameter, SPAD value and yield contributing characters such as number of flower clusters, flowers and fruits plant-1, fruit weight and fruit yield plant-1 were significantly increased with wooden bed (W) whereas earthen pot showed poor performance. In contrast, the leaf water loss as measured in percent of fresh weight was minimum at earthen pot whereas it was maximum at concrete bed. It was found that plant growing structures, different combinations of GA and Si showed significant variation on changes in morpho-physiology, yield contributing characters and fruit yield of summer tomato. Different combinations of GA and Si showed significant effect on morpho-physiological and yield contributing characters of the tomato plants. The experiment exhibited that exogenous application of 20 ppm GA and 0.4 mM Si significantly increased plant height, leaf Number plant-1, number of branches plant-1, stem diameter, SPAD value and yield contributing characters like number of flower clusters plant-1,number of flowers plant-1, number of fruits plant-1, individual fruit weight and total yield plant-1. However application of Si has reduced the leaf water loss percentage. The interaction between plant growing structure and sole or combined application of GA and Si influenced all the morpho-physiological and yield contributing characters and yield of tomato. The highest yield plant-1 (190.9g) was obtained in wooden bed with 20 ppm GA along with 0.4 mM Si (WGSi) treatment combination whereas the lowest yield (52.11g) was recorded from EH0, earthen pot and 0 ppm GA and 0 mM Si treatment combination. Therefore, this experimental results suggest that wooden bed in combination with 20 ppm GA and 0.4 mM Si can increase the production of summer tomato in the rooftop garden.