种植密度对内蒙古中部地区苜蓿生长,饲草产量及营养品质影响

为探索苜蓿优势产区内蒙古中部地区高产优质苜蓿生产中适宜的种植密度。以草原3号苜蓿为研究材料,在4个种植行距处理下(15、30、45和60cm),对其生长特征,饲草产量及营养品质进行研究。结果表明:种植密度对苜蓿茎叶比影响显著,在窄行距处理(15和30cm)下茎叶比较小,显著低于宽行距处理(45和60cm)。种植密度对苜蓿的株高、生长速度、鲜干比影响不显著。株高、生长速度随行距的增大而增加,鲜干比随行距增大而降低。种植密度对苜蓿饲草产量影响显著,饲草产量随行距的增大而减小,窄行距处理(15和30cm)下饲草产量较高。生长第2、3年苜蓿饲草产量分别在30和15cm行距下达到最大,分别为10813和12574kg·hm^-2。种植密度对粗蛋白、酸性洗涤纤维、中性洗涤纤维、相对饲用价值影响显著,对粗脂肪和灰分则不显著。粗蛋白在30cm行距下最高,中性洗涤纤维在15cm行距下最小,酸性洗涤纤维在45cm行距下最小,相对饲用价值在15cm行距下最大。综合苜蓿生长,饲草产量和营养品质等指标,内蒙古中部地区苜蓿生产适宜种植行距范围为15~30cm。

Effects of planting density on the growth,yield and nutritional quality of alfalfa in central Inner Mongolia

This study aimed to identify the optimal planting density for high yield and quality when growing alfalfa in central Inner Mongolia. In this study, alfalfa growth characteristics, forage yield and nutrient quality of the variety Caoyuan No. 3 were studied under four row spacing treatments (15, 30, 45 and 60 cm). The row spacing had a significant effect on the stem:leaf ratio (SLR), with SLR being lower under narrow raw spacing treatments (i.e. 15 and 30 cm row spacing treatments had significantly lower SLR than the 45 and 60 cm row spacings. The plant height and the fresh:dry ratio (FDR) increased with increased row spacing, while the forage yield decreased significantly with increased row spacing (i.e. yield was higher at 15 and 30 cm row spacings). The highest forage yields occurred in the second and third years and were 10813 kg drymatter (DM)·ha^-1 and 12574 kg DM·ha^-1, for the 30 and 15 cm row spacings, respectively. Planting density did not significantly affect crude fat and ash, but did significantly affect crude protein, acid detergent fiber, and neutral detergent fiber, as follows: crude protein was highest at 30 cm row spacing, neutral detergent fiber was lowest at the 15 cm row spacing, acid detergent fiber was lowest at the 45 cm row spacing, and the relative feed value was highest at the 15 cm row spacing. Considering all the forage yield and nutritional quality data, the recommended row spacing for alfalfa planting in the central region of Inner Mongolia is 15-30 cm.