限量灌溉对河套灌区间作小麦干物质转移与灌浆特征的影响

Effects of limited irrigation on dry matter translocation and filling characteristics of intercropping wheat in Hetao irrigated region

针对内蒙古河套灌区水资源短缺现状,为探究限量灌溉条件下间作春小麦的干物质转移与灌浆特征,掌握制约春小麦籽粒灌浆的因素,进而提高间作模式下春小麦的水分生产率,研究了限量灌溉（298、328、358和388 mm 4个水平）对间作模式（小麦/玉米间作、小麦/向日葵间作）下春小麦籽粒灌浆特征的影响。结果表明：间作向日葵模式下的小麦茎、叶干物质转移量是相同灌水处理下间作玉米模式下的小麦茎、叶干物质转移量的1.08~1.86倍与1.12~2.17倍,而颖轴干物质转移量则间作玉米模式是间作向日葵模式的1.00~1.19倍,且不同水分处理与种植模式下的小麦籽粒灌浆过程符合“S”型生长曲线,可用Logistic方程模拟;间作玉米模式下的小麦灌浆速率的峰值出现在花后25~30 d,较对照提前1.26~2.85 d,间作向日葵模式下的小麦灌浆速率的峰值出现在花后25~30 d,较对照提前1.80~2.44 d,各处理最大灌浆速率与平均灌浆速率均较对照提高,且减少了达到最大灌浆速率所需时间;小麦的活跃灌浆期则表现为灌水总量较少的处理（298~328 mm）有利于延长间作玉米模式下小麦的活跃灌浆期,而较高灌水量的处理（358~388 mm）则会延长间作向日葵种植模式下小麦的活跃灌浆期。

In order to explore the characteristics of spring wheat grain filling and dry matter translocation under the condition of limited irrigation and the factors limiting the grain filling of spring wheat, and thus to increase the water productivity of intercropped spring wheat, the influences of limited irrigation （four levels： 298, 328, 358, 388 mm） of two intercropping modes （spring wheat intercropped with maize or sunflower） on the characteristics of spring wheat grain filling were studied based on the present situation of water shortage in Hetao irrigated region, Inner Mongolia. The results showed that under same irrigation conditions, the dry matter translocation yield of wheat stem and leaf intercropped with sunflower were 1.08-1.86 times and 1.12-2.17 times as high as that intercropped with maize, respectively, while the dry matter translocation yield of wheat glume and cob under the maize-intercropped model was 1.00-1.19 times as high as that under the sunflower-intercropped model. The process of wheat grain filling was consistent with the ＂S＂ growth curve that could be simulated by a Logistic equation under different water treatments and planting modes. The wheat intercropped with maize reached a peak grain filling rate after 25-30 d of flowering, with 1.26-2.85 d in advance compared to the control treatment （wheat monoculture with 388-mm irrigation）. The wheat intercropped with sunflower reached apeak grain filling rate after 25-30 d of flowering, with 1.80-2.44 d in advance compared to control treatment. The maximum grain filling rate and average grain filling rate of wheat under the two intercropping modes with various water treatments were all higher than those under the control treatment, and the time needed for maximum grain filling rate decreased. The lower rates of irrigation （298-328 ram） were found to be conducive to extension of the active filling stage of wheat intereropped with maize, while the higher rates of irrigation （358-388 ram） were conducive to extension of the aetive filling stage of wheat intereropped with sunflower.