白三叶新品系抗寒生理特性及其相关基因表达研究

发布时间：2018-04-01 21:09

  本文选题：白三叶(Trifolium　切入点：repens.L.)新品系　出处：《内蒙古农业大学》2017年硕士论文

【摘要】：本文以白三叶(Trifolium repens.L.)新品系、海法白三叶(Trifolium repe L.cv.haifa),雷司令白三叶(Trifolium repens L.cv.Riesling)为试验材料,研究各白三叶材料种子萌发和萌发期、幼苗期、越冬期其生理指标的变化,和幼苗期基因MYB4、CBF3、CAS5在叶片中的相对表达量的多少,从而了解各白三叶材料的抗寒性能力的强弱,为深入研究白三叶的抗寒机制和培育抗寒新品种奠定了理论基础。本研究通过方差分析、相关性分析、隶属函数综合分析法处理数据,得出以下结论:1.白三叶新品系种子萌发期和幼苗期抗寒性显著高于海法白三叶和雷司令白三叶2个对照品种。低温胁迫下,白三叶新品系种子发芽率和发芽指数均高于对照品种,种子萌发期在温度胁迫下超氧化物歧化酶SOD活性、可溶性糖SS、可溶性蛋白SP含量显著高于对照品种。生长期幼苗在5℃低温胁迫下也有相同的生理变化。2.在自然越冬过程中,白三叶新品系的抗寒性显著高于对照品种。随着温度下降,白三叶新品系根部POD、SOD、CAT、SS、SP、PRO的含量均显著高于对照品种,其中PRO含量在低温胁迫下增加量最大;而MDA、REC的含量均显著低于对照品种。3.MYB4、CBF3和CAS5基因均受低温胁迫诱导表达,且在低温胁迫过程中呈现一定的变化规律。其中CBF3基因随低温胁迫时间增加,表达量持续上升,MYB4、CAS5在温胁迫过程中表达量先增加后减少;这3个基因在白三叶新品系中的表达量均高于海法白三叶和雷司令白三叶,且CBF3基因的表达量最高,MYB4最低。研究结果从抗寒相关功能基因的表达特性方面初步揭示了白三叶新品系抗逆御寒分子机制。
[Abstract]:In this paper, a new strain of Trifolium repens.L.), Trifolium repe L.cv. Haifaa and Trifolium repens L.cv. Rieslingn) were used as experimental materials to study the changes of physiological indexes in seed germination and germination period, seedling stage and overwintering stage of white clover. And the relative expression of MYB4 CBF3CAS5 gene in leaves, so as to understand the cold resistance of white clover materials. This study laid a theoretical foundation for the further study of the cold resistance mechanism of white clover and the cultivation of new cold resistant varieties. The data were processed by means of variance analysis, correlation analysis and membership function comprehensive analysis. The following conclusions were drawn: 1. The cold resistance of the new white clover line was significantly higher than that of Haifa white clover and Riesling white clover at germination and seedling stage. The seed germination rate and germination index of the new white clover line were higher than that of the control variety, and the SOD activity of superoxide dismutase (SOD) in the seed germination period was higher than that of the control. The content of soluble sugar SSand soluble protein SP was significantly higher than that of the control variety, and there were the same physiological changes under 5 鈩，

本文编号：1697291