Phenotyping for lodging tolerance in pearl millet: identification of optimal environment, plant stage, and potential traits.

Crop lodging poses a significant threat to global food security by reducing crop yields in terms of quantity and quality and causing difficulties in the harvesting process. Rainy-season crops like pearl millet encounter high-velocity winds and rain during different stages of crop growth, thus leading to drastic reductions in grain yields due to crop lodging. The aim of this study was (i) to identify the optimal environment for phenotyping, (ii) to identify trait linkages with lodging tolerance, and (iii) to identify the appropriate plant growth stages for lodging phenotyping. Hence, a four-year (2016-2019) field study was conducted at ICRISAT-India, involving 29 released and pipeline pearl millet single-cross hybrids procured from 11 seed companies and evaluated for several shoot and root traits to generate basic information to help phenotyping pearl millet for lodging tolerance. The study identified two traits, plant culm strength (PCS) and panicle girth (PG), which can differentiate between lodging-tolerant and lodging-susceptible cultivars irrespective of weather conditions. The studies indicated that lodging-tolerant and lodging-susceptible entries showed significant differences in PCS and PG values under well-watered (WW) conditions compared with water-stressed (WS) conditions. Investigations at different plant growth stages (anthesis, milky-grain, and grain-maturity) indicated that PCS and PG estimated at milky-grain and grain-maturity stages provide better differentiation between lodging-tolerant and lodging-susceptible cultivars. PCS was found to be positively correlated with culm diameter. Overall, this study provided preliminary results for phenotype pearl millet for lodging stress.