不同种植密度对大麦产量和青贮品质的影响

为探究新疆北部地区不同种植密度对不同品种（系）青贮大麦的影响,设置低（225万株/hm ²）、中（375万株/hm ²）、高（525万株/hm ²）3个种植密度,研究其对P13-3、P14-22和垦啤麦13大麦品种（系）农艺性状、干物质产量、青贮原料营养成分和青贮品质的影响。结果表明:提高种植密度会显著降低P14-22和P13-3的茎、叶比例,增加穗比例,但对垦啤麦13无显著影响。P14-22和P13-3鲜草产量在中密度下最大,大麦干物质含量随着大麦种植密度的增加而增加,但P14-22和垦啤麦13中密度和高密度下的大麦干物质含量无显著差异。增加种植密度会提高P14-22和P13-3的酸性洗涤纤维含量,降低P13-3的粗蛋白、粗脂肪和粗灰分含量。提高种植密度对大麦可溶性碳水化合物含量无显著影响,不同种植密度对青贮后大麦pH以及乳酸、乙酸、丙酸和丁酸含量的影响无显著性差异,但品种（系）对大麦青贮品质影响显著,3个品种（系）中垦啤麦13青贮后品质最好。综上所述,新疆北部地区青贮用大麦在中密度条件下有着较高的产量和营养品质。

Effects of Different Planting Densities on Biomass Yield and Silage Quality of Barley

In order to determine the effects of planting densities on different barley cultivars (lines) in northern Xinjiang, three planting densities (2.25×10 ⁴, 3.75×10 ⁴ and 5.25×10 ⁴ plant/ha) were set in this experiment. We studied the changes of multiple indexes of three barley cultivars (lines) (P13-3, P14-22 and Kenpimai 13) under the above planting densities, including agronomic traits, dry matter, nutritional composition of silage raw materials and silage quality. The results showed that increasing sowing density could significantly reduce the proportion of stems to leaves and increase the proportion of panicles of P14-22 and P13-3, but it had no significant effect on Kenpimai 13. The maximum fresh weight was achieved under medium density and maximum dry matter content was increased significantly in medium and high planting densities. In this experiment, increasing planting density could increase the contents of neutral and acid detergent fiber, decrease the contents of crude protein, crude fat and crude ash of P13-3. The increase in planting density had no significant effect on the content of soluble carbohydrate. There was no significant difference in pH and contents of lactic acid, acetic acid, propionic acid and butyric acid under different planting densities. In three barley cultivars (lines), Kenpimai 13 was the best one on quality after silage. To sum up, silage barley in northern Xinjiang has high yield and nutritional quality under the condition of medium density.