不同生育时期干旱对冬小麦氮素吸收与利用的影响  

Effects of drought on N absorption and utilization in winter wheat at different developmental stages

作　　者：刘恩科[1,2] 梅旭荣[1,2] 龚道枝[1,2] 严昌荣[1,2] 庄严[1,2] 

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,北京100081 [2]农业部旱作节水农业重点开放实验室,北京100081

出　　处：《植物生态学报》2010年第5期555-562,共8页Chinese Journal of Plant Ecology

基　　金：国家"十一五"科技支撑计划资助项目(2006-BAD29B01和2006BAD29B02);国家自然科学基金(30871447);中国博士后科学基金(20080440461);中央级公益性科研院所基本科研业务费专项项目共同资助

摘　　要：以抗旱性强的‘石家庄8号’和抗旱性弱的‘偃麦20’冬小麦(Triticum aestivum)为材料,在田间遮雨棚条件下,研究返青-拔节期、拔节-开花期和灌浆后期3个生育期不同干旱程度对冬小麦产量、氮素吸收、分配和利用的影响。结果表明,在干旱条件下,抗旱性强的‘石家庄8号’产量高于抗旱性弱的‘偃麦20’,并且其3个生育时期轻度干旱均可提高产量。拔节-开花期干旱对两个冬小麦品种氮素的吸收和运转影响均最大,其次为返青-拔节期,而灌浆后期影响较小。不同生育期中度和重度干旱均降低了花前贮藏氮素向籽粒中的转移,并且氮肥利用效率和生产率也较低,而在返青-拔节和灌浆后期轻度干旱有利于营养器官的氮素向籽粒中转移,提高了氮肥利用效率和生产率。在干旱条件下,抗旱性强的‘石家庄8号’籽粒氮素积累对花前贮藏氮素再运转的依赖程度高,而‘偃麦20’对花后氮素的积累和转移依赖较高。综合产量和氮素的转移特点,在生产实践中,返青-拔节期和灌浆后期要注意对小麦进行适度的干旱处理,在拔节-开花期要保证冬小麦的充分灌溉,从而有利于氮素的积累和分配。Aims Our objective was to investigate the effects of different water stress levels on yield, N absorption, allocation and utilization in winter wheat cultivars ＇Shijiazhuang 8＇ （drought resistant） and ＇Yanmai 20＇ （drought sensitive） during different growth durations. Methods We divided the growing stages of winter wheat into recovering-jointing, jointing-flowering and late filling. Soil water levels based on field capacity were 75%-80% （control, full water supply or well-watered）, 65%-70% （light drought stress）, 55%-60% （medium drought stress） and 40%-45% （severe drought stress） from winter wheat seeding to maturity and were controlled by irrigation and mobile rain shelters. Important findings The drought resistant cultivar ＇Shijiazhuang 8＇ had a higher grain yield than ＇Yanmai 20＇ under drought stress, and medium drought stress in all the three durations can increase winter wheat yield. Drought stress in the jointing-flowering stage has the greatest effects on N assimilation and translocation in winter wheat, the second greatest being in the recovering-jointing stage, while that in late filling stage has few effects. Both medium and severe drought stress during different growth durations will lower the translocation of stored nitrogen before anthesis into grain, as well as N utilization rate and productivity; on the other hand, light drought stress in the recovering-jointing and late filling stages can improve the translocation of stored N into grain as well as N utilization rate and productivity. Under drought stress, N accumulation in grain of drought-resistant ＇Shijia- zhuang 8＇ relies more on the retranslocation of stored N before anthesis, while that of ＇Yanmai 20＇ relies more on the N accumulation and translocation after anthesis. Considering yield and N translocation of wheat, light drought stress during the recovering-jointing and late filling stages is necessary, as well as sufficient irrigation during jointing-flowering stage, so as to improve N accumulat

关 键 词：不同生育期 氮素吸收 利用 水胁迫 冬小麦 

分 类 号：S512.11[农业科学—作物学]