施氮和干旱锻炼后复水/复旱对小麦水分利用效率的影响  

Effects of Nitrogen Application and Rewatering and Redrought after Drought Priming on Water Use Efficiency of Wheat

作　　者：邢佳伊 李丽[1] 王超 邢换丽 郝卫平[1] 王耀生 XING Jia-yi;LI Li;WANG Chao;XING Huan-li;HAO Wei-ping;WANG Yao-sheng(Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences/State Engineering Laboratory of Efficient Water Use of Crops and Disaster Loss Mitigation/Key Laboratory of Dryland Agriculture,Ministry of Agriculture and Rural Affairs,Beijing 100081,China)

机构地区：[1]中国农业科学院农业环境与可持续发展研究所/作物高效用水与抗灾减损国家工程实验室/农业农村部旱作节水农业重点实验室,北京100081

出　　处：《中国农业气象》2021年第3期181-189,共9页Chinese Journal of Agrometeorology

基　　金：国家重点研发计划政府间国际科技创新合作重点专项(2018YFE0107000)。

摘　　要：以“XR4347”冬小麦品种为供试作物,在温室内开展盆栽试验。试验设置不施氮(N0)和施氮(N1,1.5g·盆^(-1))2个氮素水平,每个水平下设置3种水分处理模式,即全程充分灌水(CK)、干旱锻炼后复水(PW)和干旱锻炼后复旱(PD),研究施氮和干旱锻炼后复水/复旱对冬小麦水分利用效率的影响。结果表明:干旱锻炼后复旱使植株水势降低。与CK和PW处理相比,干旱锻炼后复旱对气孔导度(g_(s))的降低作用大于光合速率(P_(n))的下降,因此,提高了叶片和植株水平的水分利用效率。在CK和PW处理下,施氮与未施氮处理相比,叶片的P_(n)和g_(s)均显著提高,而内在水分利用效率(WUE_(int),P_(n)/g_(s))小幅度增加。PD处理下,施氮对g_(s)的影响大于对P_(n)的影响,与不施氮(N0)处理相比,施氮(N1)处理下小麦叶片P_(n)增加4.5%,而g_(s)下降13.6%,因此,WUE_(int)显著提高。干旱锻炼后复旱显著降低了施氮后植株的g_(s)和耗水量,其WUE_(b)和叶片δ13C在施氮后最高,进一步表明干旱锻炼后复旱条件下施氮提高植株的WUE_(b)主要是由于气孔的调控造成的。因此,在干旱缺水地区,将干旱锻炼与施氮结合,不仅可以显著降低植株耗水量、节约灌溉用水、维持作物生长和养分吸收,还可以提高叶片和植株水平的水分利用效率。A pot experiment in the greenhouse was conducted with the variety“XR4347”of winter wheat in order to investigate the effect of rewatering/redrought stress after drought priming and nitrogen application on water use efficiency of winter wheat.The experiment included two nitrogen levels with no nitrogen(N0)and nitrogen fertilization(N1,1.5g·pot^(-1)),and three water treatments under each nitrogen level consisting of full irrigation(CK),rewatering after drought priming(PW),and redrought stress after drought priming(PD).The results showed that redrought stress after drought priming decreased the water potential of plants.Compared with the CK and PW treatments,the reduction of stomatal conductance(g_(s))of PD treatment was greater than the reduction of net photosynthetic rate(P_(n)),and therefore,the water use efficiency at the leaf and plant level was improved.Under the CK and PW treatments,the P_(n) and g_(s) of leaves were significantly increased under nitrogen fertilization compared with no nitrogen application,whereas the intrinsic water use efficiency(WUE_(int),P_(n)/g_(s))of leaves increased slightly.Under the PD treatment,the effect of nitrogen application on g_(s) was greater than that on P_(n).The P_(n) increased by 4.5%while g_(s) decreased by 13.6%,and therefore,WUE_(int) increased significantly.Furthermore,the PD treatment significantly reduced the g_(s) and the water consumption under nitrogen fertilization,and the WUE_(b) and leafδ^(13)C were the highest with nitrogen fertilization,further indicating that the higher WUE_(b) of the PD treatment under nitrogen fertilization was due to the stomatal control.Therefore,in arid and water-deficient areas,the combination of drought priming and nitrogen fertilization can not only significantly reduce plant water consumption,save irrigation water,maintain crop growth and nutrient absorption,but also improve water use efficiency at the leaf and plant level.

关 键 词：灌溉 养分 水分胁迫 气孔导度 水势 δ^(13)C 

分 类 号：S512.1[农业科学—作物学]