A huge decline in rice quality across East Asia has attribute to climate warming, as per a study publish in Geophysical Research Letters. This research, led by Dr Xianfeng Liu of Shaanxi Normal University in China, highlights the vulnerability of rice, a dietary staple for billions, to rising temperatures.
Using 35 years of data from Japan and China, the team analyse how various climate factors affect the “head rice rate” (HRR), a critical measure of rice quality base on the proportion of intact grains after milling.
The study identified warmer nighttime temperatures as the primary driver behind reduce rice quality, as per reports.
For Japan, HRR began declining at night temperatures exceeding 12 degrees Celsius and for China, the threshold was 18 degrees celsius.
Elevate nighttime temperatures during flowering and grain development phases were find to hinder photosynthesis and starch accumulation, causing more grains to break during processing.
As per reports, solar radiation emerge as the second most significant factor, with higher radiation levels link to reduce HRR.
Other contributing factors include reduce precipitation and increase daytime vapor pressure deficit, with HRR declining when the latter exceed 0.5–1 kPa.
As per many reports, projections under moderate and high greenhouse gas emissions scenarios suggest that rice quality will continue to deteriorate.
Between 2020 and 2100, HRR is expect to decline by up to 1.5% in Japan and 5% in China, with the impact intensifying after 2050 under higher emissions.
Southern regions in both countries, closer to the equator and more vulnerable to rising nighttime temperatures, face the greatest challenges.
These findings raise concerns over the adaptability of rice cultivars to climate change.
Southern provinces in China, the nation’s primary rice-growing regions, may struggle to mitigate these impacts, posing risks to food security, human nutrition, and economic stability.
The study underscores the urgent need for climate-resilient agricultural practices and crop varieties to safeguard global rice supplies.
