地膜覆盖栽培对春小麦叶片衰老特性的影响

Effect of Plastic Film Mulches on the Leaves Senescence of Spring Wheat

为了揭示春小麦在地膜栽培条件下是否早衰的问题,采用管栽模拟试验的方法,研究了地膜覆盖和露地栽培条件下春小麦叶片的叶绿素、蛋白质、叶片丙二醛(MDA)含量和细胞质膜相对透性的变化.结果表明,采用地膜覆盖栽培方法,在春小麦生长前期能明显提高叶片叶绿素和蛋白质的含量(日均增加量分别比露地春小麦高31.49%和7.94%),但后期又会加速其降解速率;MDA含量和细胞质膜相对透性均表现为覆膜处理高于露地处理(日均增加量分别比露地春小麦高71.96%～11.78%和2.42%～9.57%).说明覆膜栽培可使春小麦提前进入正常衰老阶段,但由于其增温、保湿等效应,使春小麦生长量增加,穗粒数和穗粒重比露地春小麦提高22.95%和27.68%,表现出良好的增产效应.

In order to reveal the leaves senescence of spring wheat grown with plastic film mulches, the content of chlorophyll, protein, MDA and the cell membrane permeability of the leaves for spring wheat grown with and without plastic film mulches were determined by using simulated tube cultivation. The results showed that spring wheat with plastic film mulches was able to improve the content of chlorophyll and protein of leaves in the earlier growing period and the average increase per day of the content of chlorophyll and protein of the mulched wheat increased by 31.49% and 7.94% than that of unmulched wheat respectively; but it could accelerate the decomposition of chlorophyll and protein in the later period. The content of leaf MDA and the cell membrane permeability of spring wheat with plastic film mulches were much higher than that of unmulched wheat and the average increase per day of the content of MDA and the cell membrane per meability increased by 71.96%～11.78% and 2. 42%～ 9. 57% than that of unmulched wheat respectively. Application of plastic film mulches made spring wheat arrive normal senescence stages earlier than unmulched wheat, but it increased dry matter production, grain number per spike and grain weight per spike increased 22.95% and 27.68% than that of unmulched wheat due to soil temperature increased and moisture preserved.