Synergistic Effect of Potassium and Bio Stimulants on Growth and Yield of Dolichos bean [Lablab purpureus (L.) Sweet]

Background: Field experiments were conducted at Annamalai University Farm during kharif seasons of three consecutive years from 2020-2022 to find out the effect of potassium and bio stimulants on growth and yield of dolichos bean. Methods: The experiments were conducted in RBD and replicated thrice. The treatments viz., T1- Control (without foliar nutrition), T2- Foliar application of KNO3 @ 1%+panchagavya @ 3%, T3- Foliar application of KNO3 @ 1% + panchagavya @ 6%, T4- Foliar application of KNO3 @ 1% + seaweed extract @ 2%, T5- Foliar application of KNO3 @ 1% + seaweed extract @ 4%, T6- Foliar application of potassium humate @ 1% + panchagavya @ 3%, T7- Foliar application of potassium humate @ 1% + panchagavya @ 6%, T8- Foliar application of potassium humate @ 1% + seaweed extract @ 2% and T9- Foliar application of potassium humate @ 1% + seaweed extract @ 4%. The dolichos bean variety Arka Jay was used for this study. Result: The result of present investigation indicated that the growth and yield parameters viz., plant height, branches plant-1, pods plant-1, pod length and single pod weight were found to be superior in treatment T5 as compared to control. The higher yield (15.16 t ha-1) of dolichos bean was significantly improved due to application 1% KNO3 + seaweed extract @ 4% (T5) followed by T4 and T1 over the control. The same treatment fetched the highest net return of Rs. 81626 ha-1 with a benefit cost ratio of Rs.1.79.