Agronomic and environmental perspectives on rice grain quality

Asia dominates global rice production, contributing nearly 90 % of the total output, with China and India producing over 50 % of the world's rice. Rice quality is primarily determined by head rice yield, which is influenced by genetic traits, environmental conditions, agronomic practices and postharvest handling. The global rice market values high milling recovery rates, with head rice recovery (HRR) often exceeding 50 % in premium varieties. However, high nighttime temperatures, fluctuating precipitation patterns and suboptimal storage conditions significantly degrade grain quality, leading to increased chalkiness and reduced HRR. Climate change is projected to reduce rice yields by 10–15 % per 1 °C rise in temperature, further threatening food security in monsoon-dependent regions. Utilizing crop models that integrate weather data and management practices can aid in optimizing sowing schedules and enhancing resilience in rice cultivation. This review synthesizes current research on the determinants of rice quality, examining the effects of genetic variability, drying and milling techniques and environmental stressors. Understanding these factors is crucial for improving rice production systems and ensuring long-term food security amidst climatic challenges.