Shen Z J, Ma R J, Cai Z X, Yu M L, Zhang Z
College of Horticulture, Nanjing Agricultural University, Nanjing, China.
Institute of Horticulture, Jiangsu Academy of Agricultural Sciences, Nanjing, China.
Genet Mol Res. 2015 Jan 15;14(1):101-17. doi: 10.4238/2015.January.15.13.
The fruit peach originated in China and has a history of domestication of more than 4000 years. Numerous local cultivars were selected during the long course of cultivation, and a great morphological diversity exists. To study the diversity and genetic background of local peach cultivars in China, a set of 158 accessions from different ecological regions, together with 27 modern varieties and 10 wild accessions, were evaluated using 49 simple sequence repeats (SSRs) covering the peach genome. Broad diversity was also observed in local cultivars at the SSR level. A total of 648 alleles were amplified with an average of 13.22 observed alleles per locus. The number of genotypes detected ranged from 9 (UDP96015) to 58 (BPPCT008) with an average of 27.00 genotypes per marker. Eight subpopulations divided by STRUCTURE basically coincided with the dendrogram of genetic relationships and could be explained by the traditional groups. The 8 subpopulations were juicy honey peach, southwestern peach I, wild peach, Buddha peach + southwestern peach II, northern peach, southern crisp peach, ornamental peach, and Prunus davidiana + P. kansuensis. Most modern varieties carried the genetic backgrounds of juicy honey peach and southwestern peach I, while others carried diverse genetic backgrounds, indicating that local cultivars were partly used in modern breeding programs. Based on the traditional evolution pathway, a modified pathway for the development of local peach cultivars in China was proposed using the genetic background of subpopulations that were identified by SSRs. Current status and prospects of utilization of Chinese local peach cultivars were also discussed according to the SSR information.
桃起源于中国，已有4000多年的驯化历史。在漫长的栽培过程中，人们选育出了众多地方品种，形态多样性十分丰富。为研究中国地方桃品种的多样性和遗传背景，利用覆盖桃基因组的49个简单序列重复（SSR）标记，对来自不同生态区域的158份材料、27个现代品种和10份野生材料进行了评估。在SSR水平上，地方品种也表现出广泛的多样性。共扩增出648个等位基因，每个位点平均观察到13.22个等位基因。检测到的基因型数量从9个（UDP96015）到58个（BPPCT008）不等，每个标记平均有27.00个基因型。STRUCTURE软件划分出的8个亚群与遗传关系聚类图基本一致，且能被传统类群所解释。这8个亚群分别为水蜜桃、西南桃I、野生桃、寿星桃+西南桃II、北方桃、南方脆桃、观赏桃以及山桃+甘肃桃。大多数现代品种具有水蜜桃和西南桃I的遗传背景，而其他品种则具有多样的遗传背景，这表明地方品种在现代育种计划中得到了部分利用。基于传统的演化途径，利用SSR鉴定出的亚群遗传背景，提出了中国地方桃品种演化的修正途径。还根据SSR信息讨论了中国地方桃品种的利用现状与前景。
