刈割次数对种植当年草原3号杂花苜蓿生长特性、产量及品质的影响

为了明确刈割次数对杂花苜蓿草产量、营养成分、越冬率和可持续利用所产生的影响，对种植当年草原3号杂花苜蓿进行了不同刈割次数的研究试验，并对不同刈割处理下草原3号杂花苜蓿的生长特性、干草产量、营养品质及越冬率进行了测定分析。结果表明，刈割次数对种植当年草原3号杂花苜蓿平均株高、生长速度影响不显著，而对茎叶比、鲜干比、越冬率影响显著（P〈0．05）。种植当年草原3号杂花苜蓿在刈割1次处理下的茎叶比、越冬率最高，分别为0．98、95％；在刈割2次处理下的平均株高、生长速度、鲜干比较高，分别为59cm、1．30cm／d、3．76；在刈割2次处理下的全年干草总产量最高，为5211kg／hm^2；在刈割2次处理下的粗蛋白含量和相对饲用价值平均值较高，分别为20．5％、140；在刈割2次处理下的酸性洗涤纤维和中性洗涤纤维含量平均值较小，分别为35．9％、40．6％。综合考量刈割次数对种植当年草原3号杂花苜蓿生长特性、干草产量、营养品质及越冬率的影响，种植当年刈割1次最佳。

Effect of Cutting Time on Growth Characteristics,Yield and Feeding Quality of Medicago varia Martin. cv. Caoyuan No.3 in the Year of Planting

In order to clarify the effects of cutting time on yield, nutrient composition, over-wintering rate and sustainable utilization of Medicago varia, the growth characteristics, hay yield, nutritional quality and over-wintering rate of Medicago varia Martin. cv. Caoyuan No.3 in the year of planting with different cutting time treatments were determined and analyzed. The results showed that the cutting time had no significant effect on the average plant height and growth rate of Medicago varia Martin. cv. Caoyuan No.3 in the year of planting, but had significant effects on the stem-leaf ratio, fresh-dry ratio and over-wintering rate （P〈0.05）. The highest stem-leaf ratio and the over-wintering rate were obtained in once cutting, which were 0.98% and 95%, respectively; higher average plant height, growth rate and fresh-dry ratio were observed under twice cutting treatment, which were 59 cm, 1.30 cm/d and 3.76, respectively; the highest whole-year hay yield was obtained in twice cutting, which was 5 211 kg/hm^2; the average value of crude protein content and relative feed value was higher with twice cutting treatment, which were 20.5% and 140, respectively; the average value of acid washing fiber content and neutral washing fiber content was lower with twice cutting treatment, which were 35.9% and 40.6%, respectively. Considering the growth characteristics, hay yield, nutrient quality and over-wintering rate comprehensively, one cutting time in the year of planting was recommended for Medicago varia Martin. cv. Caoyuan No.3.