覆膜与补灌对冬小麦叶绿素和比叶面积的影响

Effects of Film Mulching and Supplementary Irrigation on Chlorophyll and Specific Leaf Area of Winter Wheat

为探究不同地膜覆盖与补灌对冬小麦叶绿素、株高和叶面积的影响规律,设置不同地膜覆盖(氧化—生物双降解地膜B,普通地膜P)与拔节期补灌量(W0、W1、W2、W3)组合,对比分析了不同组合处理对冬小麦不同生育期叶绿素、株高和比叶面积的影响。结果表明,覆膜和补灌有利于提高各生育期叶绿素a和叶绿素b含量,但过量灌水效果会降低,而且B覆盖效果好于P覆盖。B覆盖叶拔节期绿素a含量随补灌量增加而增大,叶绿素b变化不大,抽穗期和灌浆期叶绿素a和叶绿素b随补灌量增加呈先增大后减小; P覆盖叶绿素a和叶绿素b含量在各生育期均随补灌量增加呈先增大后减小的趋势,在W2时达到最大值。B覆盖和补灌有利于提高拔节期叶绿素a/b值,降低抽穗期和灌浆期叶绿素a/b值。两种地膜覆盖下,补灌有利于提高冬小麦株高,过量补灌其效果减弱。各处理的比叶面积均随生育期推进而逐渐减小,W2和W3降幅较大。补灌能促进冬小麦叶片伸展和干物质积累,拔节期P覆盖效果优于B覆盖,抽穗期和灌浆期B覆盖优势显现。综合分析,降解膜覆盖结合补灌量W2(60 mm)是最优组合。

In order to explore the laws of the effect of different film mulching and supplementary irrigation on chlorophyll,plant height,and leaf area of winter wheat,the different combinations of film mulching（ bio-photodegradable B,plastic film P） and supplemental irrigation amount（ W0,W1,W2,W3） at jointing stage are set up,and the effects of different combinations on the chlorophyll,plant height and specific leaf area of winter wheat at different growth stages are compared and analyzed. The results show that the mulching and supplemental irrigation are beneficial to increase the chlorophyll a and chlorophyll b content in all growth stages,but the effect will be reduced for over-irrigation,and the B coverage effect is better than the P coverage; the content of chlorophyll a in the jointing stage of B covered leaves increases with the increase of supplementary irrigation amount,but the chlorophyll b does not change much; at the heading stage and the filling stage,the chlorophyll a and chlorophyll b first increase and then decrease with the increase of supplementary irrigation amount; The content of chlorophyll a and chlorophyll b under P covered increase at first and then decrease with the increase of supplemental irrigation amount at each growth stage,and reach the maximum at W2; The B covered and supplemental irrigation are beneficial to increase the chlorophyll a/b value at jointing stage and reduce the chlorophyll a/b value at heading stage and grain filling stage; Under the two kinds of film coverage,supplemental irrigation is beneficial to increase the plant height of winter wheat,and the effect will be weakened for over irrigation; The specific leaf area of each treatment gradually decreases as the growing period progressed,and the W2 and W3 decrease greatly; Supplementary irrigation can promote the leaf stretching and the dry matter accumulation of winter wheat; The effect of P coverage at jointing stage is better than that of B coverage,and the advantage of B coverage appears at heading stage and grain filling stage. From comprehensive analysis,the combination of B coverage and supplemental irrigation amount W2（ 60 mm） is the optimal combination.