8个新疆野苹果优良无性系抗寒性比较

为获得新疆野苹果抗寒育种的优良资源,本试验分析比较了8个新疆野苹果优良无性系在不同时期(1月、3月)的抗寒性差异,以8个新疆野苹果优良无性系的一年生枝条为试验材料,应用电导(EL)法和电阻抗图谱(EIS)法对其抗寒性进行测定与对比分析,并在3月对低温处理枝条进行了生长恢复试验。结果表明,新疆野苹果无性系的相对电导率在-20℃低温处理下开始出现显著差异。两时期由EIS法参数中r_e、r_1计算的各无性系半致死温度与EL法所求得的半致死温度的相关系数分别达到显著水平和极显著水平(0.744*、0.751*、0.822**、0.824**),说明这2种方法适用于新疆野苹果的抗寒性测定。3月的半致死温度(-33.97~-32.33℃)均显著高于1月(-31.87~-26.33℃),部分无性系间的差异达到极显著水平,各无性系在两时期的半致死温度相关性不显著。无性系M-3、M-6、M-8枝条计算的半致死温度较低,1月分别为-32.76℃、-33.97℃、-33.52℃,3月分别为-30.47℃、-30.26℃、-31.87℃;在3月的苗木生长恢复试验萌芽率较高,-30℃处理条件下分别为76.19%、75.71%、67.38%,-50℃处理条件下分别为16.67%、17.72%、18.89%。因此,无性系M-3、M-6、M-8的抗寒表现较好,是抗寒育种的优良资源。本试验结果为深入研究不同时期新疆野苹果抗寒性差异和筛选抗寒育种的优良资源提供了科学依据。

Comparison of Cold Hardiness of 8 Malus sieversii Clones

To compare the difference of cold resistance of 8 Malus sieversii clones in different periods (January and March),and select the high-quality resources of Malus sieversii,breeding for cold resistance,the cold resistance of 8 Malus sieversii clones was measured and compared by electrical conductivity method (EL) and electrical impedance spectroscopy (EIS) in two periods.The germination experiment was carried out after low temperature treatment in March.Both methods can calculate the cold resistance of Malus sieversii,according to the calculated semi-lethal temperature and germination percentage after low temperature treatment.The results showed that the relative conductivity of 8 Malus sieversii clones were significantly different at-20℃ in the periods.The semi-lethal temperature calculated by re,r1 and the conductivity method were significantly correlated in the periods(0.744*,0.751*,0.822**,0.824**);The semi-lethal temperature in March (-33.97℃ ～-32.33℃) was significantly higher than that in January (-31.87℃ ～-26.33℃),and the difference among some clones reached the extremely significant level.The semi-lethal temperature of each clone had no significant correlation at 2 periods;The calculated semi-lethal temperature of clones M -3,M-6 and M-8 were lower which were-32.76℃,-33.97℃,-33.52℃ in January,and-30.47℃,-30.26℃,-31.87℃ in March.The germination rate of clones M-3,M-6 and M-8 were higher in the growth and recovery experiment in March which were 76.19％,75.71％ and 67.38％ under-30℃ and 16.67％,17.72％ and 18.89％ at-50℃.Clones M-3,M-6 and M-8 had better performance in 2 periods'cold resistance and germination experiment,which are the good resources for cold-resistant breeding.The results provide a scientific basis for further study of cold hardiness of Malus sieversii in different periods and select high-quality resources of cold-resistant breeding.