甘南高寒牧区秋播小黑麦对氮肥施用量和播种密度的响应

本试验以甘农2号小黑麦（×Triticosecale Wittmack）为试验材料，通过研究其在高寒牧区秋播条件下株高、枝条数、干草产量、营养品质（营养价值，干物质消化率）对氮肥施用量和播种密度的响应，以确定其最佳施肥量和播种密度，为高寒牧区小黑麦的大面积示范推广提供技术支持。单因素结果表明，氮肥施用量为240 kgN·hm^-2（播种前：25%，返青期：37.50%，拔节期：37.50%）时，秋播甘农2号小黑麦的平均干草产量（15.31 kg·hm^-2）、粗蛋白含量（11.99%）和综合评价值（0.76）均较高；播种密度为843万基本苗·hm^-2时平均干草产量较高（15.11 kg·hm^-2），综合评价值（0.77）最高；氮肥施用量和播种密度间的交互作用表明，氮肥施用量为360 kg N·hm^-2、播种密度为843万基本苗·hm^-2时，高寒牧区秋播甘农2号小黑麦干草生产田的干草产量（18.71 kg·hm^-2）和综合评价值（0.80）最高。

Response of the Autumn Sown Triticale to the Nitrogen Fertilizing Rate and Seeding Density in the Alpine Grazing Area of Gannan

In order to determine the suitable cultivation techniques i.e. the optimum amount of fertilization and seeding density for Triticosecale Wittmack ‘Gannong No. 2’ in alpine pastoral area and provide technical support for the demonstration and extension of this variety,responses of the plant height,number of branches,hay yield and hay quality (nutritive values and dry matter digestibility) of autumn sown ‘Gannong No. 2’ triticale to the rates of nitrogen fertilization and seeding density were studied. Results showed that the average hay yield (15.31 kg·ha^-1),crude protein content (11.99%) and comprehensive evaluation value (0.76) of triticale were the highest when application rate of nitrogen fertilization was 240 kg·ha^-1(pre-sowing:25%,turning green stage:37.5%,jointing stage:37.5%,respectively);When the sowing density was 8.43×10⁶ basic seedlings ha^-1,the average hay yield (15.11 kg·ha^-1) and comprehensive evaluation value (0.77) of triticale were the highest. The interaction of nitrogen fertilization rate and seeding density showed that the highest hay yield (18.71 kg·ha^-1) and comprehensive evaluation value (0.80) were obtained when nitrogen fertilization rate was 360 kg·ha^-1 and seeding density was 8.43×10⁶basic seedlings ha^-1.