Physiological evaluation of growth and yield variation of mustard (Brassica juncea) varieties under organic products in North-Western Indo-Gangetic Plains

Abstract

A field experiment was conducted for two years to analyze the physiological basis of variation in the growth and yield of popular mustard varieties under organic production. Twelve mustard varieties of varied duration and agroclimatic suitability were evaluated in a randomized complete block design. Results revealed that varieties NRCHB-506, RH-406, and RGN-229, being at par, registered significantly maximum leaf area index, photosynthesis rate, and chlorophyll content at all the crop growth stages, i.e., 30, 60 and 90 DAS. During both the intervals, i.e., 30-40 and 80-90 DAS, variety RH-406 followed by RGN-229 registered maximum crop growth rate, whereas,in NRCHB-101, the lowest crop growth rate was observed. At each crop growth stage, photosynthesis rate has a significant positive correlation with leaf area index, chlorophyll content, crop growth rate during 30-40 and 80-90 DAS. Varieties Pusa Mustard-25 (5.8) and Pusa Mustard-26 (5.7) recorded significantly higher primary branches plant-1. However, varieties Pusa Tarak, RH-406, and RGN-229 recorded the significantly highest number of secondary branches plant-1. Being at par, varieties NRCHB-506, RH-406, RGN-229, and Pusa Bold recorded a significantly higher number of silique plant-1, seed yield,and stover yield than other varieties. The seed yield was found significantly and positively correlated with the crop growth rate at 80-90 DAS (r=0.600**), chlorophyll content at 90 DAS (r=0.558**), and silique plant-1(r=0.518**).Therefore, it is inferred that varieties like RH-406, RGN-229, and NRCHB-506 are suitable to grow under organic nutrient management in the prevailing agro-climatic conditions.