播种量和品种对紫花苜蓿植株动态变化、产量及品质的影响

本研究在河南农业大学科教试验园区进行,采用裂区设计,以播量(15.0,22.5,30.0kg/hm2)为主区,8个不同秋眠级苜蓿品种为副区,研究其对植株数量动态、干物质产量、营养品质的影响,旨在为苜蓿生产确定最佳播量和适宜品种,发展精准苜蓿产业提供科学依据。结果表明,(1)3种播量的越冬率无显著性变化(P0.01);但不同苜蓿品种的越冬率有差异,在85.53%~98.24%之间,其中秋眠和半秋眠苜蓿品种的越冬率都显著高于非秋眠品种,从安全越冬考虑,在河南省宜栽培秋眠和半秋眠品种。(2)播种量对植株数量动态变化有极显著影响(P0.01),随着播种量的增加,植株数量不断增加,这种变化趋势在第一生长年非常明显,但随着生长年限的延长,3种播种量的植株数量均呈现出第一生长年急剧下降、第二生长年缓慢下降、第三生长年趋于平稳一致的变化态势;植株数量随生长时间的延长尤其是在年际间变化的规律不因品种而改变。(3)播种量对年干物质产量无显著影响(P0.01),但干物质产量有随播种量增加不断提高的趋势;播种量对营养品质有一定影响,随着播种量的增加,其粗蛋白质(crude protein,CP)和粗脂肪(ether extract,EE)含量、相对饲喂价值(relative feed value,RFV)有上升的趋势,中性洗涤纤维(neutral detergent fiber,NDF)、酸性洗涤纤维(acid detergent fiber,ADF)含量有下降趋势。(4)不同品种对干物质产量和营养品质有一定的影响,从高产和品质综合考虑,以先行者最适合在郑州地区种植;播量在22.5~30.0kg/hm2情况下,有利于提高苜蓿的产量和品质。综上,在河南以种植半秋眠品种为宜,不同播量的苜蓿品种其植株数都有随生长期的延长而减少最后恒定的趋势,在适宜播量范围内,有利于提高苜蓿的产量和品质;在生产实践中,可根据生产目的和播种量选择适宜的品种。

Effects of seeding rate on plant number,production performance’ and quality of alfalfa

To determine the effects of seeding rate on the quantity,production performance,and quality of different alfalfa varieties,we used a split-plot design with three seeding rates (15.0 kg/ha,22.5 kg/ha,30.0 kg/ha) as the main plot,and eight different fall-dormant alfalfa varieties as the subplots.The results showed that the wintering rate ranged from 85.53％-98.24 ％,and did not differ significantly among the three seeding rates for any of the alfalfa varieties.The dormant and semi-dormant alfalfa varieties had higher wintering rates than those of non-dormant alfalfa varieties.Therefore,dormant and semi-dormant alfalfa varieties should be cultivated in Henan Province.The seeding rate significantly affected the number of plants.As the seeding rate increased,the number of plants increased,especially in the first growing year (2011.10.5-2012.10.6).On the whole,as the number of cultivation years increased,the number of alfalfa plants decreased sharply at an early stage (2012),decreased slowly at the middle stage (2013),and stayed the same at the later stage (2014).The seeding rate did not affect the dry matter yield of alfalfa.In the first year,as the seeding rate increased,the dry matter yield of alfalfa increased slightly,but there was no significant difference among the three treatments.Over the three growing years,the dry matter yield was higher for the middle seeding rate (22.5 kg/ha) than for the other two seeding rates.The seeding rate affected alfalfa plant quality.The crude protein content,ether extract,and relative feed value increased with increasing seeding rate,and the neutral detergent fiber and acid detergent fiber contents decreased.The dry matter yield and nutritive value differed among the alfalfa varieties,with the Concept'cultivar showing the best yield and quality.In conclusion,it is advisable to cultivate semi-fall dormant alfalfa varieties in Henan Province,and the sowing density should be 22.5-30.0 kg/ha.In practice,suitable varieties and seeding rates should be selected according to the intended purpose of the crop.