高产水平下水肥耦合对小麦旗叶光合特性及产量的影响

为了探讨黄淮麦区冬小麦的高产机理,在大田条件下设置不同梯度的水肥耦合模式,分析了高产水平下旗叶光合特性与籽粒产量的效应.结果表明,不同模式的水肥耦合对旗叶光合特性和籽粒产量的影响不同,总体表现为土壤水分的处理效应大于施氮量的效应.旗叶光合速率(Pn)和气孔导度(G5)均随着土壤水分的增加而升高,表现为W3(充足水分)＞W2(适宜水分)＞W1(自然降水),差异达显著水平.胞间CO2浓度(Ci)随着土壤水分的增加而降低；不同的氮肥处理,旗叶Pn和Gs随着施氮量的增加而升高,表现为N3(270 kg·hm-2)＞N2(195 kg·hm-2)＞N1(CK),Ci在不同水分条件下与施氮量的关系不尽相同.不同水肥耦合模式对水分利用效率的影响表现为W2＞W3＞W1,并以W2N2为最高,不同处理组合的籽粒产量亦以W2N2为最高.表明高产条件下W2N2水肥组合应是高产高效的运筹模式.

Effects of Water and Fertilizer Coupling on Photosynthetic Characteristics in Flag Leaves and Yield of Winter Wheat under High Yield Condition

Water and fertilizer are key factors affecting the growth and development of wheat. A field experiment was carried out to study the effects of different water and fertilizer coupling on photosynthetic characteristics of flag leaves and grain yield under high yield condition in Huang-huai plain. The results indicated that the different modes of water and fertilizer coupling had different influences on the photosynthetic characteristics of flag leaves and grain yield, and the overall performance of the soil moisture treatment was greater than that of the nitrogen application. The photosynthetic rate of flag leaves (Pⁿ) and stomatal conductance of flag leaves (G^s) were significantly increased with increasing of soil moisture and the order was that W3 (plenty of water) >W2 (suitability moisture)> W1 (natural rainfall), while intercellular CO₂ concentration of flag leaves (Cⁱ) reduced with increasing of soil moisture. When applied to different nitrogen treatments,flag leaf Pⁿ)and G^s increased with the increase of the amount of nitrogen and showed as N3 (270 kg·hm^-2)> N2 (195 kg·hm^-2)> N1 (CK), while Cⁱ in different amounts of nitrogen shares no similarity with different water conditions. However, different water and fertilizer coupling mode of water use efficiency showed as W2> W3> W1, and W2N2 was demonstrated the best treatment combinations whether in water use efficiency or grain yield. All of this indicates that W2N2 may be the high yield and high efficiency model under high yield condition.