云南旱地小麦新品种产量和品质对减量施氮的响应

Responses of yield and quality of new dryland wheat varieties to reduce application rate of nitrogen in Yunnan

【目的】分析减量施氮对小麦产量及品质的影响,为给云南省小麦保优、节本、高效栽培技术中合理施用氮肥提供理论依据。【方法】采用两因素随机区组设计,以新育成的旱地小麦品种云麦76和云麦77为材料,设置5个减氮梯度,即:300 kg/hm^(2)(N1)、240 kg/hm^(2)(N2)、180 kg/hm^(2)(N3)和120 kg/hm^(2)(N4)和不施氮肥(N5),测定不同处理下小麦籽粒产量及构成因素和品质相关指标,并对籽粒产量与穗数、穗粒数、千粒重3个因素进行相关性分析。【结果】在不同施氮处理下,云麦76和云麦77的产量均是随着施氮量减少而减低,施氮量由300 kg/hm^(2)减至240 kg/hm^(2)时,减产不显著,减幅分别为1.38%和0.30%;施氮量减少至180 kg/hm^(2)及以下时,减产显著。产量构成因素上,单位面积穗数随施氮量的减少显著降低,施氮量对千粒重和穗粒数的影响不显著;产量与构成因素间的相关性分析表明,产量与穗数呈极显著正相关(相关系数0.92),与穗粒数相关性不显著,而与千粒重呈显著负相关。在施氮180 kg/hm^(2)和不施氮处理下,云麦77的产量较云麦76分别高10.67%和28.87%,且在同一减氮处理下,云麦77的产量降幅远低于云麦76。品质方面,蛋白质含量和湿面筋含量随着施氮量的减少呈下降趋势,差异显著;沉降值、稳定时间和形成时间对施氮量的响应因品种而异,云麦76的沉降值随施氮量的减少呈先降后增的趋势,减氮处理对云麦77的沉降值无显著影响;形成时间和稳定时间随施氮量的减少而不同程度降低。【结论】云麦77是耐低氮小麦品种。综合考虑产量和品质,在本试验条件下,该地区常规施氮量为300 kg/hm^(2)时,能实现小麦产量和品质的协同提高。

【Objective】The present paper aimed to provide theoretical basis for rational application of nitrogen fertilizer to wheat,effects of reduced application rates of nitrogen on yield and quality of wheat were analyzed in Yunnan province.【Method】Using a two-factor randomized block design,the newly bred dryland wheat varieties Yunmai 76 and Yunmai 77 were used as materials to set up a nitrogen-use efficiency experiment including 5 N application rates,namely,300 kg/hm~2(N1),240 kg/hm~2(N2),180 kg/hm~2(N3)and 120 kg/hm~2(N4)and no nitrogen fertilizer(N5),respectively.The related indexes of grain yield,yield components and quality under different rates were determined.The correlation between grain yield and spike number,grain number per spike and 1000-grain weight was analyzed.【Result】Under different nitrogen application rates,the yield of Yunmai 76 and Yunmai 77 decreased with the decrease of nitrogen application rates.When the nitrogen application rate decreased from 300 kg/hm~2 to 240 kg/hm~2,the yield decreased by 1.38%and 0.30%,respectively;When the nitrogen application rate decreased to 180 kg/hm~2or below 180 kg/hm~2,the yield was significantly decreased.In terms of yield components,the number of panicles per unit area significantly decreased with the decrease of nitrogen application rate;However,the effect of nitrogen application rate on 1000-grain weight and grain number per spike was not significant.The results of correlation analysis between yield and components showed that there was a extremely significant positive correlation between yield and panicle number(R=0.92).There was no significant correlation with grain number per spike,but a significant negative correlation with 1000-grain weight.Under the rateof N180 kg/hm~2 and no nitrogen application,the yield of Yunmai 77 was 10.67%and 28.87%higher than that of Yunmai 76,respectively,and the yield decrease of Yunmai 77 was much lower than that of Yunmai 76 under the same N treatment.In terms of quality,protein content and wet gluten content decreased with the decrease of nitrogen application rates,and the differences were significant;The responses of sedimentation value,stability time and formation time to nitrogen application varied with different varieties.The sedimentation value of Yunmai 76 decreased at first and then increased with the decrease of nitrogen application rate,but the nitrogen reduction rate had no significant effect on the sedimentation value of Yunmai 77.【Conclusion】Yunmai 77 is a wheat variety with tolerant low nitrogen.Considering the yield and quality comprehensively,under the experimental conditions,when the conventional nitrogen application rate in this area is 300 kg/hm~2,the synergistic improvement of wheat yield and quality can be realized.