摘要
明确降水变化对冬小麦叶片形态和生物量的影响,有助于了解冬小麦在水分环境变化条件下形态和产量上的响应。试验采用人工遮雨棚和自流滴灌系统来实时人工干预降水,研究了黄土塬区三种降水条件:正常降水(CK)、降水减少1/3(R-1/3)和降水增加1/3(R+1/3)下冬小麦不同生育期的叶片形态、生物量及株高变化。结果表明:降水增加,叶长相对变化较大,叶面积增加;降水减少,叶宽相对变化较大,叶面积减少。但叶形系数((叶长×叶最大宽)/叶面积)不受降水变化的影响,仅和冬小麦的生育期有关。降水增加,冬小麦的叶片、生物量以及株高均保持稳定的生长优势;降水减少,冬小麦叶片、生物量以及株高的生长呈现"先促后抑"的现象。不同降水处理的冬小麦生物量和叶面积均呈明显的线性正相关,减少降水处理的冬小麦生物量对叶面积变化最敏感。总之,在黄土塬区冬小麦通过叶片形态、叶面积和生长速率的改变来影响光合产物积累和产量形成,以适应不同的水分环境。
Determining the effects of rainfall change on winter wheat leaf morphology and biomass can help understand the responses of winter wheat morphology and yield to water environment change in the loess tableland.We took a real-time rainfall control technique composing of artificial rainfall-shields and gravitational trickle irrigation system to investigate the effects of three rainfall treatments such as normal rainfall(CK),rainfall reducing 1/3(R_(-1/3)),and rainfall increasing 1/3(R_(+1/3))on leaf morphology,biomass and stem length of winter wheat in the different growth periods in the loess tableland.The results indicated that the leaf length relatively changed more and the leaf area increased in the treatment of R_(+1/3).While in the treatment of R_(-1/3),the leaf width relatively changed more and the leaf area decreased.The leaf shape index[(leaf length×leaf maximum width)/leaf area]was hardly affected by rainfall change and yet mainly depended on the growth period of winter wheat.In the treatment of R_(+1/3),winter wheat leaves,biomass and stem length all kept stable growth superiority in the whole growth period.While in the treatment of R_(-1/3),they were all promoted in the beginning period and restrained in the later period.Winter wheat biomass and leaf area were positively linearly correlated under different rainfall conditions.Winter wheat biomass was the most sensitive to the changes of leaf area in the treatment of R_(-1/3).Generally,winter wheat can change its leaf shape,leaf area and growth speed to affect photosynthate accumulation and yield so as to adapt different water environments in the loess tableland.
出处
《水土保持研究》
CSCD
北大核心
2016年第6期116-121,共6页
Research of Soil and Water Conservation
基金
国家自然科学基金(41371242
41530854)
中国科学院"西部之光"
中国科学院重点部署项目(KFZD-SW-306)
关键词
降水变化
叶片形态
生物量
冬小麦
黄土塬区
rainfall change
leaf morphology
biomass
winter wheat
loess tableland
