水稻幼穗分化期的抗旱性研究与综合评价

Comprehensive Evaluation of Drought Resistance During Rice Panicle Differentiation Stage

利用56个不同来源的水稻品系,在温室抗旱筛选平台通过孕穗期干旱胁迫,测定光合作用、蒸腾速率、抗活性氧等8个生理指标,结合隶属函数分析方法对所有材料进行综合抗旱能力评价,并调查了待测品系在干旱处理与对照条件下主要产量相关的农艺性状。干旱处理后的气孔阻抗值和冠层温度显著高于正常处理,表明水稻幼穗分化期干旱胁迫处理主要影响水稻的光合和蒸腾作用。利用主成分分析和隶属函数分析方法对水稻品系抗旱性进行了综合评价,最终筛选出3个幼穗分化期高抗水稻品系。同时,对产量相关农艺性状的分析结果表明,产量性状中的结实率与综合抗旱能力D值显著相关,可作为衡量水稻幼穗分化期抗旱性的产量性状指标。

This research was conducted to study the effects of drought on rice growth during rice panicle differentiation stage and to screen for drought-tolerant germplasm. Drought tolerance of 56 candidate rice lines during rice panicle differentiation stage was investigated by measuring 8 physiological indicators related with photosynthesis,photosynthesis transpiration rate,and anti-ROS on the greenhouse screening platform. The agronomic yield traits were also measured under the normal and stressed conditions. The results showed that the value of stomata resistance and canopy temperature under drought stress were significantly higher than CK,suggesting that drought stress mainly affect the changing of photosynthetic rate and transpiration characteristics during this period. In addition,3 highly drought resistant rice strains were screened out from the tested materials through principal component analysis and subordinate functions values analysis. Finally,the comparison of main agronomic characteristics under drought and irrigation showed that seed set was significantly correlated with comprehensive drought resistance capability D value and could be used as the yield trait index during rice panicle differentiation stage.