不同轮作模式对后茬作物小麦产量及生理指标的影响

本研究在前茬作物分别是种植4年的苜蓿田,玉米田,大豆田的情况下,研究了3种轮作模式(苜蓿-小麦;大豆-小麦;玉米-小麦)对其后茬作物小麦产量(籽粒产量、出籽率、地上部生物量)与小麦的生理指标(叶色值、叶面积指数、净光合速率、蒸腾速率、硝酸还原酶活性)之间的影响。结果表明:苜蓿-小麦轮作模式下比玉米、大豆轮作小麦模式会显著提高后茬作物小麦产量,而后2种模式在产量上差异不显著。苜蓿-小麦轮作模式显著改善小麦旗叶叶色值、叶面积指数,提高了小麦在灌浆期和成熟期的净光合速率、降低了在孕穗期的蒸腾速率;苜蓿-小麦轮作模式显著提高了小麦生长在整个生长期间的硝酸还原酶活性。说明此种轮作模式有利于改善后茬作物小麦对氮肥的利用率、提高其产量。

Effects of rotation systems on yields and physiological indicators of wheat

The aim of this study was to determine the effects of three planting patterns (alfalfa-wheat, AW; soybean-wheat, SW; and corn-wheat, CW) on the yields (grain yield, seed production rate, and biomass of above ground parts) and physiological indicators (SPAD value, leaf area index, net photosynthetic rate, transpiration rate, nitrate reductase activity) of wheat. The yield of wheat was significantly higher in AW than in SW and CW, and not significantly different between SW and CW. The SPAD value and leaf area index of flag leaves were significantly higher in AW than in SW and CW in every important period of wheat growth. The net photosynthetic rate of wheat was higher at the later filling and maturity stages, while the wheat transpiration rate significantly decreased at the booting stage. The activity of nitrate reductase was higher in AW than in SW and CW during the whole growing period of wheat. These results indicate that the AW pattern is suitable for optimal use of nitrogen fertilizer by wheat to improve its yields.