摘要
为探讨紫花苜蓿新品系在低温环境下的变化及响应机制,以4份苜蓿新品系(P1、P2、P3、P4)以及地方品种陇东苜蓿为材料,在低温胁迫(4℃)下分别处理0 d(CK)、1 d、13 d与20 d后测定其幼苗形态、生理与光合等指标。结果表明:随低温胁迫时间延长,供试苜蓿株高、地上与地下生物量、根冠比、根系活力、叶绿素a、叶绿素b、类胡萝卜素、叶绿素总含量、蒸腾速率、净光合速率、气孔导度及地上、地下部生长素、玉米素、赤霉素均显著降低(P<0.05);水分利用效率、丙二醛与地上、地下部脱落酸均显著升高(P<0.05);气孔限制值、过氧化物酶、超氧化物歧化酶和过氧化氢酶活性均先升后降并在胁迫13 d时达最大值,胞间CO_(2)浓度先降后升并在胁迫13 d时达最小值。隶属函数综合评价显示供试材料抗寒能力依次为P4>P2>P1>P3>陇东,线性回归分析表明地上部赤霉素、株高、地下部赤霉素、地下部玉米素可作为苜蓿苗期抗寒性评价首选指标。研究结果以期为抗寒苜蓿新品种选育提供理论依据。
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 lowtemperature 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℃).The results showed that as the duration of low temperature stress increased,plant height,aboveground and belowground biomass,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 efficiency,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 CO_(2) 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 preferred indices for evaluating the cold resistance of alfalfa seedlings.These findings provide a theoretical basis for breeding new alfalfa cultivars with cold-resistant.
作者
马香香
南丽丽
王利群
杨丽丽
焦龙光
郭佳雨
田戈
何蓉
MA Xiangxiang;NAN Lili;WANG Liqun;YANG Lili;JIAO Longguang;GUO Jiayu;TIAN Ge;HE Rong(College of Pratacultural Science,Gansu Agricultural University/Key Laboratory of Grassland Ecosystem,Ministry of Education/Key Laboratory of Forage Gerplasm Innovation and New Variety Breeding of Ministry of Agriculture and Rural Affairs,Lanzhou 730070,China)
出处
《中国草地学报》
北大核心
2025年第5期66-77,共12页
Chinese Journal of Grassland
基金
国家自然科学基金(32160327)
财政部和农业农村部:国家现代农业产业技术体系(CARS-34)。
关键词
紫花苜蓿
抗寒性
内源激素
隶属函数
回归分析
Alfalfa
Cold resistance
Endogenous hormones
Membership function
Regression analysis
作者简介
马香香(1998-),女,安徽滁州人,在读硕士生,主要从事牧草栽培与育种研究,E-mail:1963962817@qq.com;通信作者:南丽丽,E-mail:nanll@gsau.edu.cn。
