SSR分子标记鉴定橡胶树异源四倍体自然减倍现象  

Ploidy Reduction of Allotetraploid Hevea brasiliensis(Willd. ex A. Juss.)Müll. Arg. Revealed by SSR Markers

作　　者：张源源[1] 张勇 胡彦师[1] 李维国[1] 黄华孙[1] ZHANG Yuan-yuan;ZHANG Yong;HU Yan-shi;LI Wei-guo;HUANG Hua-sun(Rubber Research Institute,Chinese Academy of Tropical Agricultural Sciences/State Centre for Rubber Breeding/Danzhou Rubber Tree Germplasm Repository,Ministry of Agriculture and Rural Affairs/Key Laboratory of Biology and Utilization of Genetic Resources of Rubber Tree,Ministry of Agriculture and Rural Affairs/Hainan Provincial Key Laboratory of Cultivation Physiology of Tropical Crops,Haikou 571101;Yunnan Honghe Institute of Tropical Agricultural Science,Hekou 661300)

机构地区：[1]中国热带农业科学院橡胶研究所/国家橡胶树育种中心/农业农村部儋州橡胶树种质资源圃/农业农村部橡胶树生物学与遗传资源利用重点实验室/海南省热带作物栽培生理学重点实验室,海口571101 [2]云南省红河热带农业科学研究所,河口661300

出　　处：《植物遗传资源学报》2021年第3期718-724,共7页Journal of Plant Genetic Resources

基　　金：国家重点研发计划(2019YFD1001105);现代农业产业技术体系(CARS-34-YZ2)。

摘　　要：植物体细胞染色体数目减少是一种罕见现象。本研究以同一份橡胶树野生种质的四倍体和嵌合体为材料,通过流式细胞术分析嵌合体中四倍体细胞比例的位置效应,利用SSR分子标记分析四倍体和嵌合体的来源途径。结果表明,嵌合体植株四倍体细胞的比例在第一蓬叶处为80.50%,在第七蓬叶位置的比例为65.58%,嵌合体中四倍体细胞比例随着植株的生长而下降。18对引物在四倍体和嵌合体中扩增出的32条带完全一致,与嵌合体的二倍体砧木中的扩增结果有28条差异条带,表明嵌合体来源于四倍体体细胞的自然减倍。18个位点中1个位点的2个等位基因相对扩增产物量为3∶1,表明该四倍体种质资源不是体细胞染色体加倍形成的同源四倍体,而是由2n卵细胞和2n花粉经有性多倍化途径形成的异源四倍体。本研究首次发现并证实了橡胶树异源四倍体体细胞减倍现象。The reduction of chromosome number in plant somatic cells is a rare phenomenon. In this study,the tetraploid and chimeric of the same wild germplasm of Hevea brasiliensis(Willd. ex A. Juss.)Müll. Arg. were used to analyze the position effect of tetraploid cell proportion in chimeras by flow cytometry,and the origins of tetraploid and chimeric identified by SSR markers. The results showed that the proportion of tetraploid cells in the chimera plants decreased to 65.58% in the seventh leaf layer from 80.50% in the first leaf layer. The 32 bands amplified by 18 pairs of primers were identical in the tetraploid and chimera,and there were 28 different bands compared with 28 bands of the diploid rootstock,indicating that the chimera was derived from the spontaneous somatic ploidy reduction of tetraploid. The peak ratio of two alleles in one of the 18 loci was 3∶1,indicating that the tetraploid germplasm was not an autotetraploid produced by chromosome doubling of somatic cells,but an allotetraploid derived from sexual polyploidization of the 2 n egg and 2 n pollen. This study discovered and proved the phenomenon of ploidy reduction of an allotetraploid in rubber tree.

关 键 词：橡胶树 野生种质 异源四倍体 减倍现象 

分 类 号：S794.1[农业科学—林木遗传育种]