苹果砧木耐盐性鉴定及其指标判定

采用ＮａＣｌ型盐渍土浸提液,对１９种苹果砧木进行了耐盐性测定。以相对生长量(ＲＧ)和盐害指数(ＳＩ)为指标进行聚类分析,将其划分为耐盐能力高Ｈ(３．０ｍｇ/ｇ)、中Ｍ(２．５ｍｇ/ｇ)、低Ｌ(２．０ｍｇ/ｇ)３组,其中Ｌｕｏ－２、Ｌｕｏ－１、珠眉海棠(Ｍａｌｕｓ ｚｕｍｉ Ｒｅｈｄ．)属于Ｈ组,Ｌｕｏ－２优选株系耐盐能力达３．５ｍｇ/ｇ。通过判别分析表明,以３．０ｍｇ/ｇ和３．５ｍｇ/ｇ两个盐浓度下的ＲＧ和ＳＩ值可以准确鉴定苹果砧木耐盐能力的高低,且有利于把Ｈ、Ｍ和Ｌ区分开来。ＲＧ与ＲＩ显著负相关,均可以单独作为苹果砧木耐盐能力鉴定指标。

Salt-Tolerance Identification on Apple Rootstocks

Salt tolerance of 19 species or genotypes of apple rootstocks,including 2 new clones was measured with salt solu-tion extracted from NaCl-typed salt soil. According to cluster analysis with the relative growth (RG) and salt tolerance index(SI), the experimented rootstocks were classified into three groups with salt tolerance: High (H,≈3.0 mg/g),Middle (M,≈2.5 mg/g) and Low (L, ≤2.0 mg/g). Luo-2, Luo-1 and M.zumi Rehd. were in group H in which the clone of Luo-2 with 3.5mg/g salt tolerance was screened. Discriminant analysis showed RG or SI under 3.0mg/g and 3.5mg/g could accurately dif-ferentiate the levels of salt tolerance and were favorable for dividing three groups H, M and L. RG or SI were negative correla-tion significantly,and be used alone as identification index.