组培品种黑珍米与供体的形态差异及其RFLP分析

Studies on the Differences between Tissue Culture Variety Heizhenmi and Its Donor by Conventional and RFLP Analysis

由水稻组织培养后代选育的品种黑珍米与亲本Basmati 370相比,其形态性状,如株高,每穗总粒数,穗长,单株有效穗数,千粒重和生育期等发生了显著变化;并且使原来的白稃尖和白谷壳变成了紫稃尖和紫色谷壳,应用分布于12条水稻染色体的121个DNA探针分析黑珍米与其亲本的RFLP,结果表明:有24.8％的探针检测到了多态性,分布于10条染色体。结合4种限制性内切酶(EcoRⅠ,BamHⅠ,HindⅢ和XbaⅠ)分析的67个DNA探针中,18个探针检测到多态性,其中14个只能在一种酶检测到多态性,是由点突变引起;而其他4个能在3种或4种酶同时检测到多态性,是由插入或缺失引起。说明组培产生的无性系变异主要来源于点突变。

Tissue culture variety Heizhenmi was compared with its donor variety Basmati 370. Significant differences were observed on several characters, insluding plant height, number of total grains per panicle, growth duration, panicle length, effective panicles per plant and 1000-grain weight. Mutations of purple hull and purple apiculus were also discovered. RFLP analysis with 121 DNA probes on 12 rice chromosomes detected allelic differences between Heizhenmi and Basmati 370 at 30 loci(24. 8%)istributed on 10 chromosomes. In 67 marker loci assayed with 4 different restriction enzymes (EcoR Ⅰ, BamH Ⅰ , HindⅡand XbaⅠ), allelic differences were detected at 18 loci, among which 14 loci were caused by point mutation, and 4 loci by insertion or deletion. This result suggesed hat point mutation might be a main source of so-maclonal variation.