Improving lodging resistance while maintaining high grain yield by promoting pre-heading growth in rice

Abstract

Abstract Biomass production and translocation, grain yield, and plant lodging resistance are interconnected in rice. In order to identify a feasible way to achieve both high grain yield and improved plant lodging resistance in rice, this study compared characteristics of biomass production and translocation, grain yield, and lodging resistance traits between rice crops grown in two years (2019 and 2020) with contrasting weather conditions (mainly different levels of daily solar radiation). Results showed that crop N uptake, crop growth rate, and biomass production were 12–21% higher during the pre-heading period but 20–45% lower during the post-heading period in 2019 compared to 2020. Translocation of pre-heading biomass to panicles was 68% higher in 2019 than in 2020. Stem and leaf sheath biomass at 0, 7, 14, and 21 days after heading and straw biomass at maturity were 10–32% higher in 2019 compared to 2020. Panicle-straw ratio at maturity was 10% lower in 2019 than in 2020. The difference in grain yield was not significant between 2019 and 2020. Plant lodging load was 173% higher whereas plant lodging index was 55% lower in 2019 compared to 2020. The results of this study suggest that improving lodging resistance while maintaining high grain yield can be achieved by promoting pre-heading growth in rice.