Effect of plant bio-regulators on the growth, yield and physico- chemical characteristics of onion (Allium cepa L.)

Abstract

This experiment was held to study about the efficacy of concentration of plant bio regulators on vegetative growth, yield and quality characters of onion cv. NHRDF-RED-2 under Lucknow subtropical condition having dry climate and high pH soil (8.2). The experiment comprised of 13 treatments [Control (water spray), GA 3 @ 50, 100 ppm, 150 ppm; NAA @ 50 ppm, 100 ppm, 150 ppm and combination of GA 3 and NAA] laid out in the Randomized Block Design with three replications. The observations revealed that the application of T 11 [GA 3 @ 100 ppm + NAA @ 100 ppm] was better for improvement of growth i.e. plant height (76.50 cm), number of leaves (8.27), length of leaves (60.60) and basal diameter (2.05 cm) at 90 DAT. It also recorded the highest bulb yield (60.34 t/ha), fresh weight (90.51 g), dry weight (10.89 g), diameter (6.87 and 6.87 cm equatorial and polar, respectively) of onion bulb. Similarly, chemical properties like TSS (12.03° B) and pH (6.99) was found better under treatment T 11 (GA 3 @ 100 ppm + NAA @ 100 ppm) followed by T 9 (GA 3 @ 50 ppm + NAA @ 150 ppm). Thus, the study suggested that combined application of bio regulators (GA 3 @ 100 ppm + NAA @ 100 ppm) may be followed to get better growth, yield and quality of onion cv. NHRDF-RED-2 under drier subtropical climate.