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苦荞在中国具有广泛的栽培种植地区,长时间演化形成了丰富的遗传多样性。为了研究和利用苦荞资源,以国内北方苦荞产区(内蒙古、青海、陕西、山西、甘肃)、西南苦荞产区(西藏、四川、贵州、云南)、国内其他地方品种(江西、安徽、湖北、湖南、广西)及国外品种(尼泊尔)共计67份苦荞材料为研究对象,PCR扩增其PAL基因并测序。在此基础上分析苦荞的遗传多样性,并采用NJ法(neighbor-joining)对67份苦荞材料构建系统进化树。结果表明,供试的67份苦荞材料的PAL基因序列长度为2011 bp,其中,变异位点为160个,占序列总长度的7.9%,简约信息位点为33个,占序列总长度的1.64%,突变的类型主要是碱基的转换与颠换,高变异位点均集中在外显子2的N端。不同来源的苦荞材料间的遗传距离分布于0.002~0.016之间,来源于中国四川组的苦荞材料种内平均遗传距离最大(0.016),中国内蒙古组的最小(0.002)。中国四川地区的材料与其他地区来源的材料间的遗传距离位于0.010~0.016之间,而其他地区间的遗传距离为0.004~0.013。67份苦荞材料的平均π值和θ值分别为0.0034和0.0143。其中,中国四川材料的π值为0.0148。基于PAL基因序列构建的NJ进化树中,67份苦荞材料分为7个类群,分类与地理来源无关。仅中国西藏来源的5份材料聚集为一类,说明PAL基因序列较为稳定,多数材料间变化差异较小。中国四川地区的苦荞材料具有丰富的遗传多样性,中国西藏地区的某一材料中有较多的SNP位点,推测中国西藏的部分材料可能存在突变的热点区,预示着PAL基因新的突变位点区域。
Tartary buckwheat in China has a wide range of cultivation areas, a long time evolution has formed a wealth of genetic diversity. In order to research and utilize the resources of tartary buckwheat, the main producing areas of bitter buckwheat in Inner Mongolia (Inner Mongolia, Qinghai, Shaanxi, Shanxi and Gansu), the southwest buckwheat producing areas (Tibet, Sichuan, Guizhou and Yunnan), other domestic varieties , Hubei, Hunan and Guangxi) and foreign cultivars (Nepal), a total of 67 tartary buckwheat materials were selected as the research objects. The PAL gene was amplified by PCR and sequenced. Based on this, the genetic diversity of tartary buckwheat was analyzed, and phylogenetic tree was constructed on 67 tartary buckwheat materials using neighbor-joining method. The results showed that the length of the PAL gene sequence of the 67 tartary buckwheat materials tested was 2011 bp, of which there were 160 mutation sites, accounting for 7.9% of the total length of the sequence and 33 parsimony information sites, accounting for the total sequence length 1.64%. The types of mutations are mainly base conversion and transversion. The high variation sites are all concentrated on the N-terminal of exon 2. The genetic distance between tartary buckwheat materials from different sources ranged from 0.002 to 0.016. The average genetic distance (0.016) within tartary buckwheat from China Sichuan group was the lowest (0.002) in Inner Mongolia. The genetic distance between the materials in Sichuan, China and the materials from other regions is between 0.010 and 0.016, while the genetic distance between other regions is 0.004 and 0.013, respectively. The average pi and theta values of tartary buckwheat materials are 0.0034 and 0.0143. Among them, the value of π in China’s Sichuan material is 0.0148. Among the NJ phylogenetic trees based on PAL gene sequences, 67 tartary buckwheat materials were divided into seven groups, and their classification was unrelated to geographical origin. Only five materials from Tibet of China gathered into one group, which showed that PAL gene sequence was stable and the difference between most materials was small. The genetic diversity of tartary buckwheat in Sichuan of China is abundant. There are many SNPs in a material in Tibet of China. It is speculated that there may be some hot spots in some of the materials in Tibet of China, indicating a new mutation of PAL gene Site area.