20个烟草品种低温逆境下发芽和苗期生理生化特性的变化及耐寒性评价

摘要

试验对低温逆境下20个烟草品种发芽和苗期生理生化特性变化进行分析,并对其耐寒性进行鉴定.在常温(20～30℃)和低温(11℃)逆境下测定种子发芽特性及幼苗生长、生理生化等指标,将各性状在低温与常温下测定值的比值作为耐寒性评价指标.相关性分析表明,相对发芽率,相对发芽指数,相对活力指数和相对丙二醛(MDA)含量之间显著相关,是较好的耐寒性评价指标.通过聚类分析,将20个品种分为耐寒型、中等耐寒型和低温敏感型3类,聚类结果与相关性分析结果一致.%The cold tolerance of 20 tobacco cultivars at germination and seedling stages were investigated by determining germination characteristics, seedling physiological and biochemical characteristics at normal temperature (20 -30℃ ) and low temperature ( 11℃ ) stress.The ratios (relative values) of traits at low temperature to those at normal temperature were used to assess cold tolerance.The correlation analysis showed that the relative values of germination percentage, germination index, vigor index and malonaldehyde content were significantly correlated to each other,which were suitable for evaluating cold tolerance.By cluster analysis, 20 tobacco cultivars were grouped into three classes: cold tolerance, intermediate cold tolerance and cold sensitivity, and the results were consistent with that of correlation analysis.