根域限制下水氮供应对膜下滴灌棉花叶片光合生理特性的影响  

Effects of water and nitrogen under root restriction on photosynthetic characters of cotton plants grown with under-mulch drip irrigation

作　　者：陶先萍[1] 罗宏海[1] 张亚黎[1] 张旺锋[1] 

机构地区：[1]石河子大学新疆兵团绿洲生态农业重点实验室/农学院,石河子832003

出　　处：《生态学报》2013年第12期3676-3687,共12页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(31000675);国家科技支撑计划项目(2006BAD21B02;2007BAD44B07)资助

摘　　要：在新疆气候生态条件下,采用管栽方法,选用棉花新陆早13号和新陆早33号2个品种为供试材料,通过人工限制根系垂直生长深度和水氮供应,测定棉花叶片气体交换和叶绿素荧光参数、光合物质积累等,探讨根域限制及水氮供应对棉花光合生理特性及产量形成的影响。结果表明:与对照相比,相同水氮供应条件下,根域限制处理棉花从开花期至盛絮期叶片净光合速率(Pn)、气孔导度(Gs)和光化学猝灭系数(qp)显著降低,尤其在盛铃后期至盛絮期表现明显,但潜在最大光化学效率(Fv/Fm)、实际光化学效率(ΦPSⅡ)未受到影响;盛花期和盛絮期根重均显著降低,但地上部总干物质、蕾铃干物质累积量及籽棉产量均显著高于对照。同一根域容积不同水氮处理棉花开花期至盛絮期的Pn、Gs和Fv/Fm、ΦPSⅡ、qp均表现为W1N1>W0N1>W1N0>W0N0;根域限制条件下适量水氮供应处理盛花期和盛絮期地上部总干物质和蕾铃干物质累积量均显著增加,最终单株铃数、单铃重和籽棉产量均显著高于其它处理。因此,在膜下滴灌棉花根域容积受限制条件下,通过优化生育期水氮供应,能改善叶片光合性能、增加地上部干物质积累量及其向生殖器官分配比例,是挖掘膜下滴灌棉花产量潜力和提高效益的有效途径。Cotton （ Gossypium spp. ）, which is of tropical origin, is the most economically important textile fiber crop worldwide. Water and nitrogen are two major factors that limit the photosynthetic capacity and yield of cotton. The ability to absorb water and nutrients is closely related to the size and growing space of the root system. In Xinjiang province cotton is often cultivated at a high plant density with under-mulch drip irrigation, a method that saves both water and fertilizer application. In addition, the growing space of the root system is suppressed to a certain degree. The aim of this study was to evaluate the effects of nitrogen and water supply on photosynthesis and yield of cotton with a restricted root space grown with under-mulch drip irrigation. An improved understanding of the physiological mechanisms by which cotton acclimates to water, nitrogen supply and root restriction will be useful to improve the yield potential of cotton cultivated using this method. The experiment was conducted in Xinjiang in northwestern China from March to October, 2011. Two upland cotton cuhivars, Xinluzaol3 and Xinluzao 33, were selected as the plant material. Plants of both cultivars were grown in soil columns to restrict the depth of the root system and regulate the supply of water and nitrogen. We measured netphotosynthetic rate （Pn）, stomatal conductance （Gs ）, maximum photochemical efficiency （Fv/Fm ）, photochemical efficiency of PS Ⅱ （ ФPS Ⅱ ）, PS Ⅱ photochemical quenching （%）, and the biomass of various organs at different growth stages. Under the same water and nitrogen supply from the flowering stage to the full boll opening stage, the values of qp, Gs , and Pn of root-restricted cotton plants were significantly lower compared with those of the control. This effect was greater at later growth stages. No differences in Fv/Fm and ФPS Ⅱ were observed between root-restricted and control plants. The root weight of root-restricted plants at the full flowering stage and full boll open

关 键 词：棉花 根域限制 水氮供应 光合速率 叶绿素荧光 产量 

分 类 号：S562[农业科学—作物学]