不同根型苜蓿根系发育能力研究  

Study on root system development ability of different root-type alfalfa

作　　者：南丽丽[1] 师尚礼[1] 张建华[1] 

机构地区：[1]甘肃农业大学草业学院草业生态系统教育部重点实验室甘肃省草业工程实验室中美草地畜牧业可持续发展研究中心,甘肃兰州730070

出　　处：《草业学报》2014年第2期117-124,共8页Acta Prataculturae Sinica

基　　金：国家现代牧草产业技术体系-栽培与草地管理(CARA-35);国家自然科学基金-疏勒河流域绿洲荒漠过渡带土壤盐渍化演化的特征和机制(41163002);甘肃省高校基本科研业务费-种植年限对苜蓿地土壤微生物多样性及群落结构的影响;甘肃省自然科学基金-疏勒河流域绿洲荒漠过渡带盐渍化土壤碳过程研究(1208RJZA142)资助

摘　　要：从根系发育角度对根茎型清水苜蓿、直根型陇东苜蓿、根蘖型野生黄花苜蓿和甘农2号杂花苜蓿在甘肃省天水半湿润区、兰州半干旱区和武威干旱区生长前3年的适应性进行了连续研究。结果表明,不同根型苜蓿的根系特性差异明显。根茎型清水苜蓿主根长度最短,主根直径和侧根直径均最细,侧根数较少;根蘖型野生黄花苜蓿和甘农2号的主根长度较长,主根直径和侧根直径均较粗,侧根数较多;直根型陇东苜蓿各项根系指标介于根茎型和根蘖型苜蓿之间,与根蘖型苜蓿更接近。主根直径和侧根直径在温度较高的夏秋季增长较快。不同根型苜蓿根系体积、生物量在3个生态区均表现为从表层到深层逐次递减,随着年限的增长逐年增大。对各根型苜蓿综合分析,相对来说,根茎型清水苜蓿在天水半湿润区、根蘖型甘农2号和黄花苜蓿在兰州半干旱区和武威干旱区、直根型陇东苜蓿在天水半湿润区和兰州半干旱区具有较强的根系发育能力。Alfalfa is generally credited as the world＇s most important perennial leguminous grass, with a huge potential for development and utilization. Root types of alfalfa are divided into tap rooted, branch rooted, creeping rooted and rhizomatous rooted. Many alfalfa belong to the tap rooted variety, which are fitted to be mowed. The tap rooted alfalfa has an obvious taproot and a vertical standing stem. Many variegated alfalfa be- long to branch rooted variety, which are fitted both to be mowed and grazed. The branch rooted alfalfa has many lateral roots extended in a large area and a vertical or semi-vertical standing stem, but has no an obvious taproot. Compared with no-creeping rooted alfalfa, creeping rooted alfalfa has a high resistance on cold, arid, grazing and a large shaped area. The creeping rooted alfalfa has many horizontal roots extended in a large area and many adventitious buds, and the adventitious bud became a new plant in late. Rhizomatous rooted alfalfa are used to establish grass lands both for grazing and mowing, which has a relatively low root crown. The low root crown generated a stem similar to a root and the stem became a vegetative branch in late. Review paper of the past year in retrospect, a great number of studies have been focused on collecting forage resource, introduc- tion, breeding, resistance evaluation, productivity evaluation, and genetic diversity of tap rooted and creeping rooted alfalfa at home and abroad. Mechanism, genetic characters and environment impact branch rooted of al- falfa were studied, but only a few studies have been focused on the contrast of different root types. Therefore, the ability of different root-type alfalfa to development root systems were studied for three years in senti-humid regions of Tianshui, semi-arid regions of Lanzhou and arid regions of Wuwei in Gansu Province to analyze their adaptabilities. The results showed rhizomatous rooted Medicago sativa cv. Qingshui was found with the shor- test tap root length, the thinnest diameter of tap root and

关 键 词：根茎型苜蓿 根型 根系特征 生态区 

分 类 号：S541.9[农业科学—作物学]