高寒半湿润地区不同苜蓿品种越冬期根系生理及构型特征  

Root Physiology and Characteristics of Different Alfalfa Varieties During Overwintering in Alpine Sub-humid Area

作　　者：孙万斌[1] 马晖玲[1] 周青平 陈有军 张伟 张俊超 刘文辉[3] SUN Wan-bin;MA Hui-ling;ZHOU Qing-ping;CHEN You-jun;ZHANG Wei;ZHANG Jun-chao;LIU Wen-hui(College of Pratacultural Science, Gansu Agricultural University/ Key Laboratory of Grassland Ecosystem Ministry of Education/Pratacultural Engineering Laboratory of Gansu Province/ Sino-U. S. Center for Grassland Ecosystem Sustainability, Lanzhou, Gansu Province 730070, China;Institute of Qinghai-Tibet Plateau, Southwest Minzu University/ Sichuan Zoige Alpine Wetland Ecosystem National Observation and Research Station/ Engineering Laboratory of Sichuan Provincial Development and Reform Commission, Chengdu, Sichuan Province 610041, China;Key Laboratory of Superior Forage Germplasm in the Qinghai-Tibetan Plateau, Qinghai Academy of Animal Science and Veterinary Medicine, Qinghai University, Xining, Qinghai Province 810016, China)

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 [2]西南民族大学青藏高原研究院/四川若尔盖高寒湿地生态系统国家野外科学观测研究站/四川省发改委工程实验室,四川成都610041 [3]青海省青藏高原优良牧草种质资源利用重点实验室青海大学畜牧兽医科学院,青海西宁810016

出　　处：《草地学报》2022年第4期919-930,共12页Acta Agrestia Sinica

基　　金：国家重点专项(2017YFC0504806);国家牧草产业技术体系(CARS-34)资助。

摘　　要：为明确在青藏高原海拔3500 m半湿润地区不同苜蓿(Medicago sativa L.)品种越冬期根系生理及构型特征与越冬率的关系,选取10个不同苜蓿品种,在越冬不同时期,测定根及根颈中超氧化物歧化酶、过氧化物酶、过氧化氢酶活性和丙二醛、脯氨酸、可溶性糖含量,并在越冬前挖取根系以获取根系形态特征。结果表明:返青前根颈中可溶性糖含量变化比根部剧烈;越冬率较高的苜蓿品种根系分支模式更接近于叉状分支;返青前根部脯氨酸含量、越冬初根颈可溶性糖含量、总根长、总根表面积、主根平均直径与越冬率呈极显著正相关关系(P<0.01),返青前根颈脯氨酸含量、总根体积、根尖数、分叉数与越冬率呈显著正相关关系(P<0.05);主成分分析显示分叉数、总根表面积、总根长对苜蓿越冬率影响较大。参试苜蓿在该地自然越冬过程中,根颈生理活动比根部敏感,根系发达、扩展性强的‘WL319HQ’、‘皇后’、‘太阳神’、‘驯鹿’等品种具有较好的越冬适应性。To clarify the relationship between root physiological and root configuration and overwintering rate of different alfalfa(Medicago sativa L.)varieties in the semi-humid region of the Qinghai-Tibet Plateau at an altitude of 3500 m.10 different alfalfa varieties were planted in this area.The activity of superoxide dismutase,peroxidase,catalase,and the content of malondialdehyde,proline,soluble sugars in roots and crown were determined at different stages of overwintering.The root system was picked before overwintering to obtain root morphological characteristics.The results showed that before turning green,the content of soluble sugar in the crown changed more drastically than that in roots.Alfalfa varieties with a higher overwintering rate were closer to dichotomous branches and had better cold resistance.The proline content in the roots before turning green,the soluble sugar content in the crown at the beginning of overwintering,total root length,root surface area,average taproot diameter were significantly positively correlated with the overwintering rate(P<0.01).Proline content in the crown before turning green,root volume,root tips,root forks were significantly positively associated with the overwintering rate(P<0.05).Principal component analysis showed that the root forks,root surface area,and total root length had a greater influence.During the natural overwintering process at this area,the root crown physiological activities was more sensitive than the roots of alfalfa.The varieties‘WL319HQ’,‘Alfaqueen’,‘Sun-god’and‘AC Caribou’had well-developed root systems and strong expansion with better overwintering adaptability.

关 键 词：苜蓿 越冬率 根系特征 抗氧化酶 渗透调节物质 

分 类 号：S963.223.3[农业科学—水产养殖]