不同紫花苜蓿品种根系发育能力的研究

Study on root system development ability of alfalfa cultivars

研究了12个国内外紫花苜蓿品种在渭北旱塬丘陵沟壑区根系的发育能力.结果表明,根系生物量、根系体积、侧根数在不同紫花苜蓿品种间差异显著,在土壤中从表层到深层逐渐递减;侧根的发生部位受不同深度土壤含水量的影响.占0～50cm土层根系生物量66.5%的根系集中分布在0～20cm土层中.而侧根发生的主要部位在0～20cm的主根段,40cm以下没有侧根发生.通过聚类分析,可把12个紫花苜蓿品种分为3类,其中WL-323ML、西香、苜蓿王、巨人在渭北旱塬丘陵沟壑区根系发育好,具有较强的根系发育能力.

Analyzing the root system development ability of twelve introduced and local alfalfa cultivars in the hilly and valley regions of Weibei highplateau.The results show that there are distinctly difference among alfalfa cultivars in root system biomass,root system volume and the number of secondary root.Vertical distribution of root system biomass,volume and secondary root are decreased from 0～10 cm depth to 40～50 cm depth.Secondary root is effected by soil water content in different depth.The secondary roots of alfalfa cultivars grow mainly from the taproot underground 0～20 cm depth,and there are no secondary roots below 40 cm depth.The ability of secondary roots are decided by the trait of cultivars.According to cluster analysis on twelve alfalfa cultivars,WL-323ML,Cimmaron,Emperor,Juren are suitable for planting on the hill and valley of Weibei highplateau due to their good root system development ability.