豇豆萌芽期耐冷性综合鉴定与评价

Comprehensive Identification and Evaluation of Cold Tolerance of Cowpea at Germination Stage

以50个豇豆品种为试验材料,测定低温胁迫下(14℃)下能够发芽的43个品种低温胁迫与常温对照的相对发芽率(RGR)、相对发芽指数(RGI)、相对发芽活力指数(RVI)、相对胚根长(RRL)、相对胚根鲜质量(RRM)、相对总鲜质量(RTM)6个指标;采用主成分分析法、隶属函数分析法、聚类分析法、逐步回归分析法对14℃条件下发芽的43个品种进行萌芽期耐冷性分析。结果表明,统计的相对发芽率(RGR)、相对发芽指数(RGI)、相对发芽活力指数(RVI)、相对胚根长(RRL)、相对胚根鲜质量(RRM)、相对总鲜质量(RTM)6个指标仅相对发芽率(RGR)与相对胚根长(RRL)的相关性不显著,其他各指标间均呈显著性正相关,利用主成分分析法和隶属函数分析法得到耐冷性综合评价D值,利用聚类分析法对D值进行分类,将参试的43个豇豆的耐冷性分为4类:Ⅰ类(耐冷型)、Ⅱ类(中度耐冷型)、Ⅲ类(耐冷较差型)、Ⅳ类(冷敏感型);利用回归分析法建立适宜评价不同豇豆品种萌芽期耐冷性的最优回归方程:D=-0.357+1.032 X2+0.404 X3+0.555 X6。研究筛选到耐冷型豇豆品种7个,冷敏感的品种9个。

Total 50 cowpea varieties were used in the experiment,43 varieties could germinate at low temperature stress(14℃).The cold resistances of 43 varieties based on six indicators:the relative germination rate(RGR),relative germination index(RGI),relative germination vigor index(RVI),relative radicle root length(RRL),relative radicle root fresh mass(RRM)and relative total fresh mass(RTM)were analyzed by principal component analysis,membership function analysis,cluster analysis and stepwise regression analysis.The results showed that the correlation was significant among the relative germination rate(RGR),relative germination index(RGI),relative germination vigor index(RVI),relative radicle root length(RRL),relative radicle root fresh mass(RRM)and relative total fresh mass(RTM)except the relative germination rate(RGR)and the relative radicle length(RRL).Through principal component analysis,6 single indexes were converted into 2 mutually independent comprehensive indexes.The D value of cold tolerance was obtained by using the principal components analysis and membership function analysis,and the cold tolerance of the 43 cow peas was divided into 4 categories by cluster analysis method:typeⅠ(Resistant),typeⅡ(Medium resistant),typeⅢ(Low resistant)and typeⅣ(Cold Sensitive);using regression analysis,the optimal regression equation for evaluating cold tolerance of different cowpea varieties at germination stage was established:D=-0.357+1.032 X 2+0.404 X 3+0.555 X 6.Seven cold-resistant cowpea varieties and nine cold-sensitive varieties were screened out.