干旱胁迫对不同生育期冬小麦叶片蛋白质和核酸含量的影响

Effect of Different Drought-stresses on the Content of Protein and Nuclear Acid in Winter Wheat Leaf in Different Growth Stages

[目的]在冬小麦不同生长发育阶段测定不同水分处理的叶片蛋白质和核酸含量,对叶片蛋白质、核酸代谢从时间、空间上进行讨论。[方法]将小麦生育期划分为出苗至拔节(前期)、拔节至开花(中期)、开花至成熟(后期)3个阶段,同时设3个水分梯度,即田间持水量的30%～40%、50%～60%、70%～80%,共9个处理,测定冬小麦叶片的蛋白质、核酸含量和叶片渗透势,分析干旱胁迫对不同生育期冬小麦叶片蛋白质和核酸含量的影响。[结果]水分胁迫下,小麦叶片蛋白质、核酸含量下降,其中蛋白质含量下降较明显。随小麦的生长发育到孕穗、灌浆阶段,叶内蛋白质、核酸含量下降,尤以核酸含量下降较早,下降幅度也较大,显示大量的N、P从叶片中运输到籽粒中,这是一种库源关系。[结论]从整个生长发育来看,干旱加速蛋白质、核酸分解,促进冬小麦器官早衰。

[ Objective] The content of protein and nucleic acid in winter wheat leaf in its different growth stages were measured after the treatments of different water in order to vertically and horizontally research the metabolism of protein and nucleic acid in leaf in the time and spatial level. [ Method] The experiment with 9 treatments including 3 growth stages： from wheat seedling to jointing （early stage）, from wheat jointing to flowering（mid-term） and from wheat flowering to maturity （late stage ） and 3 water gradients： the capacity of water in field from 30% to 40% , from 50% to 60% and from 70% to 80% was designed and the content of protein and nucleic acid and the osmotic potential of winter wheat leaf were measured for the research on drought stress affecting them. [ Results ] Under the water stress, the content of the protein and nucleic acid in wheat leaf was decreased and the obvious reduction of the content of protein appeared. With the wheat development to booting and grain filling stage, the content of the protein and nucleic acid leaf was decreasing, especially in the content of nucleic acid, which reduction appeared earlier and also the declining amount was larger, indicating a large amount of N and P was transported from leaves to grains, which was the relationship of sink-source. [ Conclusion] From view of the whole wheat growth and development, the drought stress accelerated the decomposition of protein and nucleic acid, and promoted winter wheat organs aging.