不同苜蓿品种种子发芽对温度和模拟干旱的响应:基于积温和水势模型的分析  

Germination responses of different alfalfa cultivars to temperature and simulated drought:An analysis based on thermal time and hydrotime models

作　　者：郑艳 赵明 张红香[1] ZHENG Yan;ZHAO Ming;ZHANG Hongxiang(Key Laboratory of Wetland Ecology and Environment,State Key Laboratory of Black Soils Conservation and Utilization,Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences,Changchun 130102,China;Uni-versity of Chinese Academy of Sciences,Beijing 101408,China;Institute of Botany,Chinese Academy of Sciences,Beijing 100093,China)

机构地区：[1]中国科学院东北地理与农业生态研究所湿地生态与环境重点实验室,黑土地保护与利用全国重点实验室,长春130102 [2]中国科学院大学,北京101408 [3]中国科学院植物研究所,北京100093

出　　处：《生态学杂志》2024年第7期2010-2017,共8页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(41971069)资助。

摘　　要：积温模型用于研究种子在低于和高于最适温度下的发芽响应,水势模型用于描述发芽速度与水势之间的关系。为了研究和比较不同苜蓿品种的发芽对温度和模拟干旱的响应,本研究以北方育成的6个苜蓿品种——敖汉苜蓿、东苜1号、甘农3号、公农1号、龙牧803号紫花苜蓿和草原3号杂花苜蓿为对象,以聚乙二醇(PEG 6000)模拟干旱条件,设置8个温度(5、10、15、20、25、30、35和40℃)和6个水势(0、-0.2、-0.4、-0.6、-0.8和-1.0 MPa),开展发芽试验。结果显示:不同苜蓿品种对温度和干旱的响应不同。6个苜蓿品种的萌发最低温在-2.3~6.2℃,草原3号最低,龙牧803号最高。所有苜蓿品种在20℃或35℃萌发最快,40℃高温显著抑制苜蓿发芽。萌发最低水势在-0.91~-0.68 MPa,敖汉苜蓿萌发最低水势最低,甘农3号萌发最低水势最高,-0.8和-1.0 MPa显著抑制了所有苜蓿品种的发芽。从种子发芽响应的角度,草原3号和公农1号的抗寒性较高;敖汉苜蓿和龙牧803号的抗旱性较强。这些结果为苜蓿栽培和选育提供了重要信息。Thermal time model is used to examine the germination response of seeds at temperatures below and above the optimal one,while hydrotime model is used to fit the relationships between germination rate and water potential.We examined the germination responses of six alfalfa cultivars from the northern China(viz.Aohan,Dongmu 1,Gannong 3,Gongnong 1,Longmu 803 and Caoyuan 3)to temperature and simulated drought.Polyethylene glycol(PEG 6000)was used to simulate drought conditions.Germination tests were carried out at eight temperatures(5,10,15,20,25,30,35,and 40℃)and six water potentials(0,-0.2,-0.4,-0.6,-0.8,and-1.0 MPa).Results showed that different alfalfa cultivars responded differently to temperature and drought.The base germination temperatures(Tb)for the six cultivars were between-2.3 and 6.2℃,with Caoyuan 3 the lowest and Longmu 803 the highest.Germination rate of all the cultivars was the highest at 20 or 35℃.40℃high temperature significantly inhibited germination of all alfalfa cultivars.The base water potentials(Yb)of germination for the six cultivars were between-0.91 and-0.68 MPa,with Aohan the lowest and Gannong 3 the highest.Low water potentials-0.8 and-1.0 MPa greatly inhibited germination of all alfalfa cultivars.From the perspective of seed germination response,Caoyuan 3 and Gongnong 1 are more cold tolerant,while Aohan and Longmu 803 are more drought tolerant than other cultivars.These results provide important information for alfalfa cultivation and breeding.

关 键 词：发芽速度 聚乙二醇 积温模型 水势模型 苜蓿 抗寒性 抗旱性 

分 类 号：S541.9[农业科学—作物学]