中国紫粒小麦品种(系)染色体多样性的FISH分析

Chromosome Diversity Analysis of Chinese Purple-Grained Wheat Cultivars(Lines)with FISH

彩色小麦富含花青素、酚类等生物活性成分,是改善小麦营养品质的重要基因资源,目前中国已经育成并推广了60多个彩色小麦品种,但对其染色体多样性研究尚缺乏报道。本研究以全国不同地区收集的50个紫粒小麦品种(系)为试材,寡核苷酸探针套#7(ONPM#7)FISH分析发现,49个品种(系)为染色体纯合类型,1个为染色体杂合类型,由此构建了50个核型;共发现113种染色体多态类型,出现频率介于2.0%~100%之间,其中12种多态类型出现频率大于50%,代表中国紫粒小麦的主要染色体类型。染色体多态信息含量分析表明,A染色体组变异最大,其次为B染色体组,D染色体组变异最小;单染色体中6A变异最大,3D和4D变异最小。基于染色体多态性可以将供试材料全部清晰区分,50份紫粒小麦可以分为4个亚群,其中G1-1和G1-2类群分别包含4和8个品种(系),均为T1BL·1RS;G2-1和G2-2类群分别包含12和26个品种(系),均为非T1BL·1RS。ONPM#7产生的丰富染色体带纹为彩色小麦品种识别提供了简单直观的细胞学标记。

Color-grained wheat is rich in anthocyanins,phenols and other bioactive components,representing an important genetic resource for improving wheat nutritional quality.To date,more than 60 color-grained wheat cultivars have been developed and promoted in China,but no information is available on their chromosome diversity.In this study,50 purple-grained wheat cultivars(lines)collected from different regions of China were analyzed for chromosome constitutions using oligonucleotide probe multiplex#7(ONPM#7)FISH.The results showed that 49 cultivars(lines)were homozygous and 1 cultivar was heterozygous.A total of 50 karyotypes were further developed.A total of 113 chromosome polymorphic types were found,ranging from 2.0%to 100%,and 12 of polymorphic chromosomes showed a frequency more than 50%,representing the dominant types.Chromosome polymorphic information content(CPIC)analysis showed that A subgenome varied the largest,followed by B subgenome,and D subgenome the least.Among single chromosomes,6A varied the largest,while 3D and 4D the least.Based on the polymorphic chromosomes,50 cultivars(lines)were grouped into four subgroups:G1-1 and G1-2 respectively containing 4 and 8 accessions,all of which carry T1BL·1RS,and G2-1 and G2-2 containing 12 and 26 accessions,all of which carry non-T1BL·1RS.The results indicated that ONPM#7 was a powerful tool for color-grained wheat chromosome identification.