摘要
【目的】探究不同程度水分亏缺条件下,东北地区玉米生理生态指标及产量的变化。【方法】采用盆栽方式,在玉米拔节初期(A)、拔节后期(B)、抽雄期(C)、灌浆期(G)分别设计亏水1 d、亏水3 d、亏水5 d、亏水7 d的处理和1个对照试验(充分供水,CK),研究了不同生育期水分亏缺对玉米气孔导度、耗水量及产量的影响。【结果】(1)随着亏水程度增加,叶片气孔导度也随之降低,其中C5、C7处理降低最为显著,4个生育期内亏水1、3 d的处理与CK差异较小。当土壤含水率低于0.15 cm3/cm3时,气孔导度一般低于50 mmol/(m2·s)。(2)亏水条件下作物的耗水量小于充分供水条件下作物的耗水量,其中4个生育期亏水1 d的处理变化均不明显,C3处理略微降低,4个生育期亏水5、7 d的处理与CK相比降低明显。土壤含水率小于0.15 cm3/cm3时,作物耗水量仅为正常条件下的1/3;复水后其耗水量也不能恢复到充分供水的水平。(3)整体上,玉米产量及产量性状随着亏水程度的增加而降低,严重亏水使产量平均降低了49.1%。抽雄期亏水对产量影响最明显,各处理产量及产量性状差异性显著,秃尖长的增加是产量降低的主要原因。【结论】轻度亏水处理(亏水1、3 d)对玉米生理生态指标及产量影响较小,从C3处理开始水分亏缺对其影响表现明显。抽雄期水分亏缺对玉米产量的形成不利,基于气孔导度、耗水量和产量变化,土壤体积含水率0.15 cm3/cm3可以作为判断玉米受到水分胁迫的阈值下限,抽雄期充分供水有利于高产。
【Objective】The purpose of this paper is to investigate the effects of water deficit occurring at different growth stages on stomatal conductance, evapotranspiration and yield of maize.【Method】A two-year pot experiment was carried out with water deficit occurring at stages of early jointing（A）, late jointing（B）, tasseling（C）and grain-filling（D） of maize growing in Lishu experimental station of China agricultural university in Jilin province. We examined four treatments, with water deficit lasting 1, 3, 5 and 7 days, respectively（C1, C3, C5 and C7）. The control（CK） was full irrigation without water deficit.【Result】（1）The stomatal conductance decreased with the increase in water deficit, especially in C5 and C7; when the volumetric soil water content was less than0.15, the stomatal conductance reduced to less than 50 mmol/（m2· s）.（2）Under water stress, the evapotranspiration was lower than that in the CK. Water deficit lasting for one day at any of the four growth stages did not result in noticeable detrimental impact, except C3 where the evapotranspiration only slightly decreased. In contrast, a prolonged water deficit lasting five or seven days at any stage significantly reduced the evapotranspiration compared to the CK. When the volumetric soil water content was less than 0.15, the evapotranspiration was only one third of that at normal moisture content.（3）The yield and yield traits decreased with water stress increasing, and a seven-day water deficit could reduce the average yield by 49.1%. Water stress at any stage reduced the yield, especially when occurring at the tassel period. The bald tip was the most significant trait for yield reduction.【Conclusion】We can conclude from our experiment that water deficit for one to three days had limited effect on ecophysiological traits and the yield of the maize, and the volumetric water content of 0.15 can be used as an critical water content to diagnose water deficit. We also found top-upping the moisture content to sufficient level at tasseling stage after water deficit can help achieving high yield.
作者
张智郡
刘海军
张立伟
刘钰
丁梅
朱明承
ZHANG Zhijun;LIU Haijun;ZHANG Liwei;LIU Yu;DING Mei;ZHU Mingcheng(College of Water Sciences, Beijing Normal University, Beijing 100875, China;School of Civil Engineering and Water Conservancy, Ningxia University, Yinchuan 750002, China)
出处
《灌溉排水学报》
CSCD
北大核心
2018年第4期9-17,共9页
Journal of Irrigation and Drainage
基金
水利部公益项目(201401036)
国家自然科学基金项目(51479004)
关键词
玉米
亏水处理
气孔导度
耗水量
土壤水分
产量
maize
water deficit treatment
stomatal conductance
evapotranspiration
soil moisture
yield
