玉米、花生及其间作茬口与施磷对冬小麦光合特性及产量的影响机制

该试验在玉米单作茬口、玉米-花生间作茬口(间作茬口)、花生单作茬口共3种茬口,以及0 kg P_2O_5·hm~(-2)(P_0)和180 kg P_2O_5·hm~(-2)(P_1) 2个磷水平下,研究了间作茬口与施磷对冬小麦分蘖、叶面积指数(LAI)、干物质积累、光合特性及产量的影响机制,为玉米花生间作与小麦-玉米复种轮作提供理论依据。结果表明:(1)间作茬口较玉米茬口显著提高了冬小麦有效分蘖数、LAI、净光合速率和干物质积累量,并提高了冬小麦旗叶的SPAD值、CO_2饱和点、光饱和点及最大净光合速率(P_(nmax))、表观量子效率(AQY)、羧化效率(CE)、最大羧化速率(V_(cmax))、最大RUBP再生的电子传递速率(J_(max))和最大磷酸丙糖利用速率(V_(TPU)),且CE、V_(cmax)、V_(TPU)的增幅均达到显著水平(P0.05),有效改善了冬小麦产量构成,显著提高籽粒产量(P0.05)。(2)间作茬口较花生茬口提高了冬小麦乳熟期的P_(nmax)、AQY、CE,增加了穗粒数和粒重,提高了产量。(3)与不施磷相比,施磷180 kg P_2O_5·hm~(-2)显著促进间作茬口冬小麦生长,显著提高冬小麦旗叶的SPAD值、P_(nmax)、AQY、CE、V_(cmax)、J_(max)、V_(TPU)和籽粒产量(P0.05)。研究发现,间作茬口较玉米茬口能有效增强冬小麦旗叶表观量子效率和CO_2羧化能力,显著提高小麦花后光合能力,促进冬小麦生长,从而增加穗粒数、粒重和籽粒产量,且间作茬口结合施磷180 kg P_2O_5·hm~(-2)效果更好。

Effect of Sole Maize, Sole Peanut, and Maize Peanut Intercropping Crops for Rotation and Phosphate Fertilizer on the Photosynthetic Characteristics and Yield of Winter Wheat

In order to provide a theoretical basis for a rotation between maize peanut intercropping and wheat maize multiple cropping, we studied the effects of maize intercropping peanut crops for rotation and phosphate fertilizer on tillering, leaf area index (LAI), dry matter accumulation, photosynthetic performance in flag leaves, and grain yield for winter wheat. A field experiment with three types of crops for rotation including sole maize, maize peanut intercropping, and sole peanut, and two phosphate fertilizer levels including application 0 kg P₂O₅·hm^-2 (P₀) and 180 kg P₂O₅·hm^-2 (P₁) was conducted. Results showed that: (1) compared with maize crops for rotation, maize peanut intercropping crops for rotation (intercropping crops for rotation) significantly increased the effective tillering numbers, LAI, net photosynthetic rate, and dry matter of winter wheat; The SPAD value, CO₂ saturation point, light saturation point, maximum net photosynthetic rate (P_nmax), AQY, carboxylation efficiency (CE), rubisco maximum carboxylation rate (V_cmax), maximum electron transfer rate (J_max) and triose phosphate utilization rate (V_TPU) of winter wheat flag leaves were also increased, CE, V_cmax and V_TPU enhanced to a significant level (P<0.05), and significantly improved (P<0.05) winter wheat grain yield and the composition. (2) Intercropping crops for rotation increased the P_nmax, AQY and CE in wheat flag leaves at milk stage, enhanced the kernels per spike, kernel weight and yield of winter wheat compared with peanut crops for rotation. (3) Supplying phosphate fertilizer with 180 kg P₂O₅·hm^-2 significantly improved winter wheat growth, and increased the SPAD value, P_nmax, AQY, CE, V_cmax, J_max, and V_TPU in flag leaves, and grain yield (P<0.05) in intercropping crops for rotation plots, compared with no phosphate fertilizer application. The study found that intercropping crops for rotation could effectively strengthen the apparent quantum efficiency and CO₂ carboxylation capacity in flag leaves of winter wheat, significantly enhance the photosynthetic capacity after flowering, and improve winter wheat growth. Thus, the kernels per spike, kernel weight and grain yield of winter wheat were increased, and intercropping crops for rotation combining with 180 kg P₂O₅·hm^-2 phosphate fertilizer could get more effective to winter wheat.