摘要
Rice yield stability is a breeding goal,particularly for short-growth duration rice,but its underlying mechanisms remain unclear.In an attempt to identify the relationship between yield stability and source–sink characteristics in short-growth duration rice,a field experiment was conducted at three sites(Yueyang,Liuyang,and Hengyang)in 2021 and 2022.This study compared yield,yield components,source–sink characteristics,and their stability between two stable-yielding short-growth duration rice cultivars,Zhongzao 39(Z-39)and Lingliangyou 268(L-268),and two unstable-yielding short-growth duration rice cultivars,Zhongjiazao 17(Z-17)and Zhuliangyou 819(Z-819).The stability of agronomic parameters was represented by the coefficient of variation(CV).The respective CVs of yield in Z-17,Z-819,Z-39,and L-268 were 10.2%,10.1%,4.5%,and 5.7%in 2021 and 19.7%,15.0%,5.4%,and 6.5%in 2022.The respective CVs of grain weight were 6.3%,5.7%,3.4%,and 4.5%in Z-17,Z-819,Z-39,and L-268 in 2021,and 8.1%,6.3%,1.5%,and 0.8%in 2022.The mean source capacity per spikelet and pre-heading non-structural carbohydrate reserves per spikelet(NSC_(pre))were 7%–43%and7%–72%lower in Z-819 and Z-17than in L-268 and Z-39 in 2021 and 2022.The mean quantum yield of photosystem II photochemistry of leaf,leaf area index,and specific leaf weight of L-268 and Z-39 were higher than those of Z-819 and Z-17 at the heading stage.This study suggests that high NSC_(pre),caused by great leaf traits before heading,increases source capacity per spikelet and its stability,thereby increasing the stability of grain weight and yield.Increasing NSC_(pre)is critical for achieving grain weight and yield stability in short-growth duration rice.
基金
the National Natural Science Foundation of China(32001470)
the Scientific Research Fund of Hunan Provincial Education Department(21B0184)
The Science and Technology Innovation Program of Hunan province(2021RC3088).
