免耕留茬抛秧栽培模式对水稻生育后期叶片衰老特性的影响

以穗型差异较大的3个杂交稻组合富优I号、D优527、冈优881为材料，研究了不同栽培方式下水稻生育中后期叶片的衰老特性及机制。结果表明，免耕留茬抛秧提高了水稻抽穗后叶片的SPAD值和可溶性蛋白含量，降低了叶片的POD(过氧化物酶)活性，提高了生育后期(抽穗21 d后)叶片的SOD(超氧化物歧化酶)和CAT(过氧化氢酶)活性，3种酶协同作用，降低了活性氧自由基产生速率和MDA(丙二醛)含量，从而延缓了植株衰老。

Effect of Cultivation Method of Broadcasting Rice Seedlings in the Field with Standing-Stubbles under No-tillage Condition on Senescence Characteristics of Leaves during Late Stages of Rice Development

Three panicle types of hybrid rice combinations Fuyou I, D you 527, and Gangyou 881 were used to investigate the effects of different tillage and cultivation methods on the senescence characteristics and mechanism in middle and latter periods of rice. The results showed that, the SPAD value and soluble protein content (SPC) of leaf after heading were increased by the treatment of broadcasting rice seedlings in the field with standing-stubbles under no-tillage condition (BSNT). Activity of peroxidase (POD) was decreased, but activities of superoxide dismutase (SOD) and catalase (CAT) in the late growth duration (21 days after heading) were enhanced by the treatment of BSNT. For BSNT, rate of reactive oxygen free radical (O₂^?) production speed and malondialdehyde (MDA) content were lower than those for other treatments. Therefore, treatment of BSNT effectively delayed senescence of plant.