根瘤菌拌种量对库布齐沙地紫花苜蓿生长的影响

在内蒙古库布齐沙地研究了根瘤菌拌种比例对紫花苜蓿(Medicago sativa)生长和结瘤的影响。紫花苜蓿品种为"4010",按根瘤菌与苜蓿种子的质量比,设0、10、20g·kg~(-1) 3种处理,测定株高、根瘤数随时间的变化和两茬的产量和营养含量。结果表明,根瘤菌拌种对苜蓿株高、根瘤、产量以及第1茬的茎叶比和营养含量均有显著影响(P0.05)。经拌种处理的根瘤数比不拌种的对照组多14倍。20g·kg~(-1)拌种时株高和产量最高,株高比不拌种高6.8cm;两茬干草总产量比不拌种高1.79t·hm~(-2);10g·kg~(-1)拌种使第1茬的茎叶比减小、粗蛋白含量增加、酸性洗涤纤维和中性洗涤纤维含量减少。产量和营养没有同时达到最佳水平,在实际应用中,还应连同生产成本等因素综合考虑,选择最佳根瘤菌用量。

Effect of Rhizobium dosage on growth of alfalfa in Kubuqi Sandland

The effect of Rhizobium dosage on the growth and nodule characteristics of alfalfa (Medicago sativa ) was investigated in Kubuqi Sandland,Inner Mongolia.The seeds of alfalfa cultivar '4010'were mixed with Rhizobium Dormal at ratios of 0,10,and 20 g·kg-1 and then sown.Each treatment had three replicates.Indi-ces of growth,nodules,yield,and nutrient contents were measured periodically.The results showed that Rhi-zobium had a significant influence on plant height,nodule formation,yield,and nutrition content at the first harvest (P <0.05).Rhizobium inoculation resulted in a 14-fold increase in nodule number compared with the 0 g·kg-1 treatment.The 20 g·kg-1 treatment resulted in the highest values for plant height and hay yield, resulting in an increase in plant height of 6.8 cm and an increase in hay yield of 1.79 t·hm-2 .The 10 g·kg-1 treatment significantly decreased the stem/leaf ratio and resulted in a higher CP content and lower Acid Deter-gent Fiber (ADF)and Neutral washing fiber (NDF)contents at the first harvest.The maximum yield and best nutrition quality were not obtained simultaneously.In practical production,factors including cost also need to be taken into account when determining the optimal Rhizobium dosage.