不同覆膜方式对玉米叶片光合、蒸腾及水分利用效率的影响

摘要

To clarify the maize(Zea mays) yield-increasing mechanism of whole film mulching, two lines of furrow sowing were done in arid and semi-arid areas. Field experiments were carried out in 2009 to study the effects of five methods of film mulching on photosynthesis rate (Pn), transpiration rate (Tr), stomatal conductance (Gs), leaf water use efficiency (LWUE) and grain yield. The Pn and Tr were highest at the bell-mouthed stage with single-peaked curves. The Pn, Gs, LWUE and grain yield under whole film mulching of two lines of furrow sowing (QS) were significantly higher than those of mulching lines of furrow sowing (QL) , semi-film mulching two lines of furrow sowing (BS), semi-film mulching of tiling bunch sowing (BP) and no film mulching of bunch sowing (CK). The Gs was significantly positively correlated with Pn and Tr, while Pn was significantly correlated with Tr. The grain yield was significantly positively correlated with Pn, Gs, LWUE from seeding stage to bell-mouthed stage and Tr from bell-mouthed stage to milking stage. The results also showed that the QS treatment improved grain yield by 24. 17%, 27. 15%, 44. 52% compared with QL, BS, BP and CK respectively and is currently the optimum pattern for maize film mulching in the Longdong area.%为进一步明确干旱半干旱地区全膜双垄沟播玉米栽培技术的增产机理,2009年采用田间试验,研究了5种覆膜方式对玉米光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、叶片水分利用效率(LWUE)及籽粒产量的影响.结果表明,不同覆膜方式下玉米Pn和Tr均呈“单峰”曲线的变化趋势,峰值出现在大喇叭口期.其中,全膜双垄沟播(QS)处理的Pn、Gs、LWUE和籽粒产量均高于全膜垄作沟播(QL)、半膜双垄沟播(BS)、半膜平铺穴播(BP)、露地穴播(CK).Gs与Pn、Tr极显著相关,Pn与Tr显著相关.籽粒产量与Pn、Gs、苗期至大喇叭口期的LWUE、大喇叭口期至乳熟期的Tr呈极显著正相关.与QL、BS、BP和CK相比,QS处理的籽粒产量分别增加24.17％,27.15％,44.52％和69.14％(P＜0.05),是目前我国陇东地区玉米的最佳覆膜方式.