Effect of bio-regulators and plant growth promoting bacteria on growth attributes of Indian bean (Lablab purpureus L. var. typicus)

Abstract

A field experiment was carried out to know the effect of bio-regulators and plant growth promoting bacteria (PGPB) on growth, yield and quality of Indian bean (Lablab purpureus L. var. typicus)” during kharif season 2017 at Horticulture Farm, S.K.N. College of Agriculture, Jobner (Jaipur).The experiment consisted of twenty treatment combinations including five bio-regulators (control, brassinoids 0.5 ppm, brassinoids 1.0 ppm, salicylic acid 100 ppm and salicylic acid 150 ppm) and four plant growth promoting bacteria (control, Rhizobium, Pseudomonas and Rhizobium + Pseudomonas). Experiment laid out in randomized block design with three replications. The results of the study clearly indicated that application of brassinoids 1.0 ppm to the Indian bean significantly increased the plant height (77.56 cm), number of branches per plant (9.82), dry matter accumulation(90.50,161.72 and 215.0 g/m row length) at 45, 60 and 75 days after sowing, respectively, CGR (26.38 and 19.73 g/m2/day) at 45-60 and 60-75 days after sowing, chlorophyll content in leaves (1.942 mg/g) and leaf area (3093 cm2) as compared to control. Similarly, seed inoculation with Rhizobium + Pseudomonas also significantly increased the plant height (76.70 cm), number of branches (10.80), dry matter accumulation (92.17,161.51 and 218.76 g/m row length) at 45, 60 and 75 days after sowing, respectively, CGR (25.68 and 21.20 g/m2/day) at 45-60 and 60-75 days after sowing, chlorophyll content in leaves (1.931 mg/g) and leaf area (3027 cm2) than control (no inoculation).