Response of Plant Growth Regulators and Boron on Seed Yield and Seed Quality of Tomato (Solanum lycopersicum L.)

Abstract

Tomato (Solanum lycopersicum L.) is an important vegetable crop widely cultivated for its nutritional and economic value. Seed yield and seed quality are crucial factors for ensuring better crop establishment and productivity. Plant growth regulators and micronutrients play a significant role in improving reproductive efficiency and seed quality parameters in tomato. Therefore, the present investigation was conducted at the Vegetable Seed Farm, Department of Horticulture (Vegetable and Floriculture), Bihar Agricultural University, Sabour, Bhagalpur, Bihar, to study the effect of plant growth regulators (NAA, GA₃, and Ethephon) and boron on seed yield and seed quality of tomato. The experiment was laid out in a Factorial Randomised Block Design with three replications. The treatments consisted of ten levels of plant growth regulators (water spray, NAA @ 50, 75 and 100 ppm; GA₃ @ 25, 50 and 75 ppm; and Ethephon @ 100, 150 and 200 ppm) and three levels of boron (0, 0.3 and 0.4%). The results revealed that both plant growth regulators and boron significantly influenced se Keywords ed quality parameters. Among the PGR treatments, NAA @ 75 ppm recorded the highest germination percentage (71.94%), whereas the lowest germination (63.67%) was observed with Ethephon @ 150 ppm. Boron application at 0.3% resulted in maximum germination (70.78%). The interaction effect showed that GA₃ @ 75 ppm combined with boron @ 0.3% produced the highest germination (76.88%). Vigour Index–I and Vigour Index–II were also significantly influenced by PGRs and boron, with the highest values recorded under NAA @ 100 ppm and GA₃ @ 75 ppm treatments. Electrical conductivity of the seed was lowest under GA₃ @ 50 ppm and boron @ 0.3%, indicating better membrane stability and seed vigour. Seed viability was highest with GA₃ @ 75 ppm and boron @ 0.4%, whereas 1000 seed weight was not significantly influenced by the treatments. Overall, the study indicated that the combined application of plant growth regulators and boron improved seed quality parameters of tomato. Among the treatments, GA₃ @ 75 ppm along with boron @ 0.3% proved most effective in enhancing germination and seed vigour of tomato seeds under field conditions.