在甘南州高海拔地区研究了海拔高度和密度对饲用甜菜品种甜饲2号生物学性状的影响，结果表明，海拔高度与饲用甜菜生长势、发病率和产量均呈负相关。种植密度对饲用甜菜生育前期生长势的影响不明显，生育后期生长势、单根重和产量均随种植密度的增加呈先增加后减小的趋势。在同一海拔下，种植密度7.5万株/hm2的产量均高于其他处理，较种植密度4.5万株/hm2处理分别增产30.29%(海拔2 737 m)和19.35%(海拔3 040 m)。由效应方程可得，在甘南州海拔 2 700 m左右的地区饲用甜菜的最佳种植密度为7.43万株/hm2，海拔3 000 m左右的地区最佳种植密度为7.81万株/hm2。

The experiment was set up to study the effects of the altitude localities and plant density on the biological characteristics of forage sweet corn cultivar Tiansi 2 in the high altitude 2 737 m and 3 040 m area of Gannan. The results showed that it was negatively correlated between the altitude and the growth potential， plants incidence and the yield of forage beet. The effect of planting density on growth potential was not obvious. The growth potential， single root weight and yield increased with the planting density firstly and then decreased in later stage. Compared with 45 000 plants/m2 treatment and 60 000 plants/m2 treatment， the yield of 75 000 plants/m2 treatment was higher at the same altitude. The yield under 75 000 plants/m2 treatment increased by 30.29%(2 737 m) and 19.35%(3 040 m)， respectively. By the equation to be seen that the optimal planting density of forage beet was 74 300 plant/hm2 in the area about altitude 2 700 m in Gannan， and 78 100 plant/hm2 in the altitude 3 000 m. In conclusion， we can obtain the higher by increasing plant density.

S566.3

甘肃省农业科学院农业科技创新专项科技支撑计划项目“功能性甜菜种质资源引进筛选及种质创新”(2016GAAS06)；甘肃省农业科学院农业科技创新专项院地科技合作项目“高海拔地区饲用甜菜新品种引进试验与示范”(2017GAAS56)。