Effects of water stress on growth indexes and yield of semilate rice at different growth stages under rain shelter
In order to find out the effects of different degrees of drought stress on the growth index and yield of semilate rice,a pot experiment was conducted with hybrid rice"Tianyouhuazhan".Three water stress levels of light drought,moderate drought and severe drought were set at tillering stage,booting stage,heading stage and milk stage,and normal intermittent irrigation was used as control(CK)to monitor soil moisture content.The plant height,number of tillers,chlorophyll content and leaf area under different water gradients at different growth stages were measured,and the effects of different drought stress at different growth stages on rice growth index and yield were analyzed.The results showed that drought stress had the most significant effect on plant height at jointing and booting stage,tillering stage had the most obvious effect on tiller number and leaf area,and heading and flowering stage had the greatest influence on chlorophyll synthesis and the highest daily water requirement.The most sensitive period of drought stress to yield was heading and flowering stage.Different stress levels reduced the effective panicle number,1000-grain weight and seed setting rate of rice.Compared with the normal level(CK),the yield of the three stress levels decreased by 27.57％,44.23％and 46.32％,respectively.Correlation analysis showed that the correlation degree of affecting yield was 1000-grain weight,seed setting rate and effective panicle.Therefore,ensuring water supply at heading and flowering stage can effectively improve 1000-grain weight,effective panicle and seed setting rate,and increase rice yield and water use efficiency.
万方数据
维普
