淹水胁迫对不同中稻品种的生理及产量的影响研究OA

In order to study the response of different mid-season rice varieties to flooding stress,Huanghuazhan,Tianyouhuazhan,and Longliangyouhuazhan-major mid-season rice varieties in the middle and lower Yangtze River-were selected as research subjects.Through pot experiments,three flooding depths of 1/2(H1),2/3(H2)and full flooding(H3)and three flooding durations of 3 d(T1),6 d(T2)and 9 d(T3)were set up.The effects of flooding stress on plant height,tillering,relative chlorophyll content and yield of mid-season rice were systematically analyzed.Based on the correlation between relative yield and flooding factors,a drainage model was constructed to analyze the allowable time of drainage under different flooding depths,which provided a theoretical basis for the formulation of drainage indicators in irrigation areas.The results showed that flooding stress promoted plant height elongation,inhibited tillering and relative chlorophyll content,plant height elongation was significantly negatively correlated with tillering inhibition,and the stress response of each physiological index had significant variety specificity.The yield decreased significantly with the increase of flooding depth and duration,and the flooding tolerance thresholds varied considerably among varieties.Path analysis showed that seed setting rate was the core driving factor of yield loss.Based on data from rice flooding tolerance tests,the relationship equation between relative rice yield and cumulative flooding depth during the flooding period can serve as a drainage model for rice.Taking 10%~30%reduction of rice yield as the drainage standard,the drainage time under different flooding depths can be determined based on the regression equation.