Spatial analysis of nuclear and mitochondrial RFLP genotypes in populations of the chestnut blight fungus, Cryphonectria parasitica
Spatial analysis of nuclear and mitochondrial RFLP genotypes in populations of the chestnut blight fungus, Cryphonectria parasitica
复制标题
板栗疫病真菌 Cryphonectria parasitica 群体核和线粒体 RFLP 基因型的空间分析
作者：
M. Milgroom;S. Lipari
采用多种空间自相关检验方法，对栗疫病菌几个种群的核型和线粒体RFLP的空间结构进行了研究。从受感染的板栗树上采集真菌个体，并绘制每棵树的位置图。测定每个个体的单基因座核RFLP、核指纹和线粒体DNA单倍型。在五个样地中的四个样地中，具有相同DNA指纹基因型的个体发生的距离比随机预期的更近，而线粒体DNA单倍型在所有五个样地中都聚集在一起。在五个群体中的四个群体中，个体间的遗传距离与个体间的欧几里得距离显著相关(r<；0.18)，用1减去指纹和线粒体单倍型共有的限制性片段大小类别的比例表示。相同的DNA指纹和单拷贝核RFLP等位基因出现在同一棵树或紧邻的树上的频率比随机预期的要高。所有三个遗传标记的大部分聚集发生在同一簇板栗茎内的个体之间或邻近的树木上。一个种群缺乏空间自相关性可能是由于较大规模的采样太粗糙而无法检测到任何模式。寄生毛囊线虫的显著基因聚集性很可能是由于种群内某种程度的限制扩散所致。讨论了限制扩散的含义与繁殖系统和在种群中的距离隔离。寄生毛囊线虫。
Spatial structure of both nuclear and mitochondrial RFLPs were studied in several populations of the chestnut blight fungus, Cryphonectria parasitica, using a variety of spatial autocorrelation tests designed to detect nonrandom patterns. Fungal individuals were sampled from cankers on infected chestnut trees, and the location of each tree was mapped. Single‐locus nuclear RFLPs, nuclear fingerprints, and mitochondrial DNA haplotypes were determined for each individual. Individuals with the same DNA fingerprint genotypes occurred closer together than would be expected at random in four of the five plots, while mitochondrial DNA haplotypes were aggregated in all five plots. Genetic distances between individuals, expressed as one minus the proportion of shared restriction fragment size classes for fingerprints and mitochondrial haplotypes, were significantly correlated with Euclidean distances between individuals in four of the five populations, but these correlations were very weak (r < 0.18). The same DNA fingerprint and single‐copy nuclear RFLP alleles occurred on the same trees or immediately neighbouring trees more often than would be expected at random. Most of the aggregation for all three genetic markers occurred among individuals within the same cluster of chestnut stems or on neighbouring trees. Lack of spatial autocorrelation in one population was probably due to sampling on a larger scale that was too coarse to detect any patterns. Significant aggregation of genotypes in C. parasitica is most likely caused by some degree of restricted dispersal within populations. The implications of restricted dispersal are discussed in relation to the breeding system and isolation by distance in populations of. C. parasitica.
影响因子：
3.3
作者：
M. Nei;F. Tajima
通讯作者：
M. Nei;F. Tajima