种植密度和行距配置对紫花苜蓿群体产量及品质的影响

摘要

以甘肃省主栽品种甘农3号紫花苜蓿(Medicago sativa cv.Gannong No.3)为研究对象,研究了甘肃荒漠灌区播种量(12,16,20和24 kg· hm-2)和行距配置[3种等行距10、15和20 cm,2种宽窄行距6行×10 cm(窄)+40 cm(宽)和6行×10 cm(窄)+30 cm(宽)]对其干草产量、茎叶比及营养成分的影响.结果表明,不同的行距处理中,20 cm行距的苜蓿干草产量显著高于15、10cm和两种宽窄行距(P＜0.05);不同的播种量处理中,播种量为16 kg·hm-2的苜蓿年总干草产量显著大于20,24和12 kg·hm-2(P＜0.05).播种量为16 kg·hm-2、行距为20 cm时,初花期苜蓿粗蛋白、粗脂肪、中性洗涤纤维、酸性洗涤纤维、钙、磷含量分别为21.89％、3.59％、33.69％、30.98％、1.34％、0.11％,其粗蛋白含量和年干草产量(32 841.71 kg·hm-2)显著高于其它处理(P＜0.05).从产量和营养品质综合考虑,该地区播种量为16 kg·hm-2、行距为20 cm是高产、稳产的最佳配置.本研究结果对苜蓿的栽培与管理有一定的指导意义.%This report describes the effects of seed sowing rate and row spacing on yield,stem:leaf ratio and nutrient composition of Medicago sativa cv.Gannong No.3 grown in the arid desert region of Gansu.Total yield was the highest when row spacing was 20 cm,which was significantly higher than other spacing of 15,10 cm,and two kinds of wide and narrow row spacing of planting rows.Total yield was also significantly higher at a seeding rate of 16 kg· ha-1 compared to other seeding rates of 20,24 and 12 kg · ha-1.Crude protein,crude fat,neutral detergent fibre,acid detergent fibre,calcium,and phosphorus contents were 21.89％,3.59％,33.69％,30.98％,1.34％,and0.11％ at early flowering stage,respectively.Total yield was 3.28 t· ha-1 and the total crude protein content was 21.89％,and both these were significantly higher at 16 kg · ha-1 seeding rate and 20 cm row spacing compared to all other treatments.Therefore,this may be the optimal combination,as it scored the highest in grey relational analysis on the comprehensive evaluation of major nutrients.These results offer valuable guidance for cultivation and management of alfalfa.