灌水和追氮对冬小麦植株性状和产量的影响

为了明确灌水和追氮对冬小麦茎秆性状和产量的影响，以‘京9428’为材料，分析了不同时期灌水和追氮对小麦茎秆性状及产量和产量构成因素的影响。结果表明，春3、4叶期一次性肥水使基部第一、二节间显著较长，穗下节显著较短，株高显著较低，公顷穗数和穗粒数显著较少，产量显著较低。春3、4叶期灌水后春5叶期灌水追肥的处理，虽然基部节间也较长，但穗下节间显著较长，株高显著较高，公顷穗数和穗粒数显著较多，产量显著较高，其他处理的结果处于以上二者之间；灌水和追氮都能显著提高小麦顶部功能叶光合速率，但春5叶期较春3、4叶期灌水追氮显著提高开花后冬小麦顶部功能叶的光合速率；灌水和追氮时期对单株茎数和单茎干重影响不大。该区域小麦春季肥水以春3、4叶期灌水，春5叶期一次性追肥较适宜。

The Effect of Topdressing Nitrogen and Irrigation on Plant Traits and Yield of Winter Wheat

To clarify the effect of topdressing time of nitrogen and water on stem traits and yield of winter wheat, the field experiment was designed with seven topdressing time of nitrogen and water with winter wheat cultivar‘Jing 9428’as material, the stem straits, yield and its composition of winter wheat were studied in the experiment, and the relationship of grain yield with yield components and stem straits of winter wheat was analyzed. The results showed that the nitrogen fertilization and irrigation were applied when the third or fourth spring leaf emerged, the bottom first or second internode was elongated significantly, the uppermost internode length was significantly short, the plant height was significantly small, the number of head per hectare and grain number per head were significantly less, and the yield was significantly low. But in contrary, if nitrogen fertilization and irrigation were applied in the stage of the spring five leafs after irrigated in the stage of spring three or four leafs, longer bottom internode could be expected. The effects of the other treatments were not significant. The top function leaves Pn was enhanced significantly after irrigation or topdressing nitrogen, compared with that at the third or fourth stage, topdressing nitrogen and water at the fifth leaf stage enhanced significantly the Pn after the blossom. The effects of different topdressing time of nitrogen and water on stem number and dry matter per plant were little. It is suggested to carry out fertilization and irrigation in the stage of spring three or four leafs, and supplying fertilization in the stage of spring five leafs in this area.