施氮对不同小麦品种干物质分配、氮素吸收和产量的影响

为了解不同小麦品种对氮肥的敏感性,以西农979和小偃22为参试品种,对其分别进行了五个水平的施氮处理,并分析了不同施氮量处理对两个品种营养器官干物质对籽粒的贡献率、各器官含氮量、分蘖成穗和产量的影响。结果表明,随着施氮量的增加,两个品种茎鞘、穗轴+颖壳、叶中干物质转运量及干物质对籽粒贡献率均呈减少的趋势,施氮后西农979干物质对籽粒贡献率平均减少14.23%,小偃22平均减少18.50%;两品种器官含氮量均以籽粒最高,茎鞘最低,且随施氮量的增加呈增加趋势;随着施氮量增加,两品种千粒重降低,穗数、穗粒数以及产量均呈先增加后减少的趋势。与小偃22相比,西农979花前各器官干物质转移量及其对籽粒的贡献率均较低,但其具有更强的花后同化能力;施氮后,西农979在冬春分蘖与穗数增加方面均优于小偃22,产量提高幅度也相对较大,在施氮180 kg·hm-2时产量最高,说明西农979对氮肥反应较小偃22敏感。

Effects of Nitrogen Fertilizer Application on Distribution of Dry Material, Assimilation of Nitrogen and Yield of Different Wheat Varieties

In order to understand the responding sensitivities of different wheat variety to application of nitrogen fertilizers, taken wheat variety Xinong 979 and Xiaoyan 22 as the test material, five application levels of nitrogen fertilizer were used to examine contribution of organs to seeds, nitrogen content, tiller, spikes and field yield. The results showed that stem sheath, spike, kernel shell and transportation of dry material decreased with increasing amount of nitrogen applied, After application of nitrogen, the contribution rate decreased 18.5% in Xiaoyan 22, 14.23% in Xinong 979. The content of nitrogen in two varieties was the highest in kernel and the lowest in the stalk and the nitrogen in each organ increased with input of nitrogen content. With increasing nitrogen input, one-thousand seed weight decreased, and spike number and spike particle number increased at first but then decreased. In contrast with Xiaoyan 22, the transfer of dry material in Xinong 979 and contribution rate to the seeds were averagely lowered, however, the assimilation of Xinong 979 was even stronger than that of Xiaoyan 22 after anthesis. After application of nitrogen, the spring-winter tillers in Xinong 979 is more than that in Xiaoyan 22 as well as field yield. In total, Xinong 979 yield its maximum with application of nitrogen at 180 kg·hm^-2, while the yield of Xiaoyan 22 peaked at 240 kg·hm^-2.