中国草地学报2025，Vol.47Issue(5)：66-77,12.DOI:10.16742/j.zgcdxb.20240346
紫花苜蓿新品系幼苗对低温胁迫的响应
Responses of Seedlings from New Alfalfa Lines to Low Temperature Stress
摘要
Abstract
This research focused on four new alfalfa(Medicago sativa)lines(P1,P2,P3,and P4)and local M.sativa cultivar 'Longdong' to explore the changes and response mechanisms under low-temperature conditions.The morphological,physiological,and photosynthetic parameters of seedlings were measured at 0 d(CK),1 d,13 d,and 20 d under low-temperature stress(4 °C).The results showed that as the duration of low temperature stress increased,plant height,aboveground and belowground bio-mass,root-shoot ratio,root activity,chlorophyll a,chlorophyll b,carotenoids,total chlorophyll content,transpiration rate,net photosynthetic rate,stomatal conductance,and the contents of auxin,zeatin,and gibberellin in aboveground and belowground were decreased significantly(P<0.05).Water use effi-ciency,malondialdehyde content,and aboveground and belowground abscisic acid were significantly risen(P<0.05).The stomatal limitation value,along with the activities of peroxidase,superoxide dismutase,and catalase showed an initial increase followed by decrease,reaching their peak at 13 d under stress.In contrast,the intercellular CO2 concentration decreased initially and then increased,with the minimum value occurring at 13 d under stress.The comprehensive evaluation with the membership function indicated that cold resistance was ranked as P4>P2>P1>P3>'Longdong'.Linear regression analysis revealed that aboveground gibberellin,plant height,underground gibberellin,and belowground zeatin can be the pre-ferred indices for evaluating the cold resistance of alfalfa seedlings.These findings provide a theoretical basis for breeding new alfalfa cultivars with cold-resistant.关键词
紫花苜蓿/抗寒性/内源激素/隶属函数/回归分析Key words
Alfalfa/Cold resistance/Endogenous hormones/Membership function/Regression analy-sis分类
农业科技引用本文复制引用
马香香,南丽丽,王利群,杨丽丽,焦龙光,郭佳雨,田戈,何蓉..紫花苜蓿新品系幼苗对低温胁迫的响应[J].中国草地学报,2025,47(5):66-77,12.基金项目
国家自然科学基金(32160327) （32160327）
财政部和农业农村部:国家现代农业产业技术体系(CARS-34) （CARS-34）
