苹果实生砧木种质资源耐缺铁和耐盐碱性评价

为了解苹果实生砧木资源抗逆性的种间、居群间和株系间差异及株系内性状分离,用8个种20份苹果资源的二年生实生苗和16个种81份苹果资源当年实生苗分别进行低铁、高盐和高pH胁迫处理,并调查缺铁黄化指数、盐害指数和碱害指数。山定子和新疆野苹果不同居群间3个性状的变异均小于苹果属种间差异,株系间、株系内实生苗3个性状分离程度最严重,但新疆野苹果同居群内株系间各性状的变异与种间差异相当。苹果属种质资源耐缺铁黄化和耐碱2个性状之间相关性显著,而缺铁黄化和耐盐之间、耐盐和耐碱之间不相关。筛选出草原海棠、小金海棠和楸子为耐缺铁黄化、耐盐、耐碱优异实生砧木资源。苹果属种质资源耐缺铁黄化、耐盐、耐碱3个性状不仅存在显著的种间差异,也存在显著的居群间变异,株系间和株系内的变异更广泛。

Evaluation onthe tolerance of apple seedling rootstock resources to iron-deficiency,salinity and alkalinity

This study focused on the genetic variation of the resistance of apple rootstock resources among different species,populations,lines and the segregation within the same lines.2-year-old seedlings of 20 accessions in 8Malus species and 1-year-old seedlings of 81 accessions in 16Malus species were subjected to iron-deficient,high-salt and high-alkaline treatments.Chlorosis index,salt injury index and alkali injury index were also investigated.For M.sieversii and M.baccata,the genetic variation of the 3 traits among different species was larger than that among different eco-geographical populations,and it was about the same between lines and among lines,while the segregation of the 3 traits within the same lines was more remarkable than that among species.A significant correlation between iron-deficient tolerance and alkali tolerance was detected in Malus germplasm resources,which was not significant between iron-deficient tolerance and salt tolerance or between salt tolerance and alkali tolerance.Besides,M.ioensis,M.xiaojinensis and M.prunifolia were successfully identified,displaying strong tolerance to iron-deficiency,salinity and alkalinity.Tolerances of apple rootstock resources to iron-deficiency,salinity and alkalinity differed substantially among different species,and there was also an obvious difference among eco-geographical populations,lines and individuals within the same lines.