10个白三叶品种苗期耐寒性评价

Cold tolerance assessment of 10 Trifoliumrepenscultivars at the seedling stage

采用室内人工模拟低温(10、5、0、-5℃)处理方法,以25℃为对照,对10个白三叶(Trifolium repens)品种苗期植株叶片的相对电导率(REC)、丙二醛(MDA)、游离脯氨酸(Pro)、超氧化物歧化酶(SOD)、过氧化物酶(POD)等生理指标进行测定分析。结果表明,随处理温度的降低,REC、MDA、Pro和SOD均呈逐渐上升趋势,而POD呈先升后降再升高的"N"型变化趋势。通过-5℃下生理指标聚类,可将10个品种划分出3个耐寒级别:强耐寒性的Durana、Barbzan、Dutch White,中度耐寒的Alice、Rivendel、TahoraⅡ、Huia,弱耐寒的Haifa、Tribute、Prop。这与田间自然越冬率(Barbzan>Durana>Dutch White>Rivendel≈TahoraⅡ>Alice>Tribute≈Huia>Prop>Haifa)的实测结果基本一致。

The plant leaves of ten Trifolium repens cultivars at the seedling stage were respectively exposed to 25℃(control)℃,10℃,5℃,0℃and-5℃temperature treatments.The relative electrical conductivities(REC),malondialdehyde(MDA)contents,free proline(PRO)contents,superoxide dismutase(SOD)and peroxidase(POD)activities of these treatment leaves were measured,respectively,in order to assess the cold resistance of these 10 T.repens cultivars at the seedling stage.The results showed that the REC,MDA,PRO and SOD increased with the reduction of treatment temperature and the POD exhibited the'N'type which increased firstly,then decreased and increase again.The cluster analysis of these 5physiological indices at-5℃treatment for these 10 T.repens cultivars indicated that 10 cultivars could be divided into three groups which included the strong cold tolerance cultivars(Durana,Barbzan and Dutch White),the medium cold tolerance cultivars(Alice,Rivendel,TahoraⅡ and Huia)and the weak cold tolerance cultivars(Haifa,Tribute and Prop).This cluster analysis were similar with the wintering rates(Barbzan>Durana>Dutch White>Rivendel≈TahoraⅡ>Alice>Tribute≈Huia>Prop>Haifa)in the nature field.