Vegetative compatibility and genetic analysis of Colletotrichum lindemuthianum isolates from Brazil
Vegetative compatibility and genetic analysis of Colletotrichum lindemuthianum isolates from Brazil
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DOI：
10.4238/vol10-1gmr907
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发表时间：
2011-01-01
影响因子：
0.4
通讯作者：
Damasceno e Silva, K. J.
中科院分区：
文献类型：
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作者：
Barcelos, Q. L.;Souza, E. A.;Damasceno e Silva, K. J.
菜豆炭疽病的病原菌林德木硫炭疽菌（Colletotrichum lindemuthianum）具有相当大的遗传变异性和致病性，这使得抗病品种的培育变得困难。我们研究了C.通过营养体亲和群（VCGs）鉴定和RAPD分析，对lindemuthianum的亲缘关系进行了初步研究。从不同地区、不同寄主品种和不同年份采集的47个不同致病型的菌株中，获得295个nit突变体。在互补试验中，鉴定了45个VCG。用18个RAPD引物进行分子标记分析，共扩增出111条多态性条带。估计的遗传相似性，确定的Sorence-Dice系数，范围从0.42至0.97，聚类分析得到的树状图显示18组菌株。RAPD和VCG标记显示了较高的基因型多样性。RAPD、VCG和致病性标记之间的显著关联（P = 0.05）的数量从0（VCG）到80%（致病性）不等。RAPD标记的多位点关联检验（r（d））与0有极显著差异（P < 0.001），表明存在连锁不平衡。然而，VCG标记的结果显示存在重组机制。RAPD标记和VCGs技术可用于检测炭疽菌菌株间的遗传变异。Lindemuthianum。我们发现相当大的差异，从同一地理来源的菌株在很短的时间内，这表明快速进化。有必要进一步研究，以阐明该病原体在农业生态系统中的种群结构。
The causal agent of common bean anthracnose, Colletotrichum lindemuthianum, has considerable genetic and pathogenic variability, which makes the development of resistant cultivars difficult. We examined variability within and between Brazilian pathotypes of C. lindemuthianum through the identification of vegetative compatibility groups (VCGs) and by RAPD analysis. Two hundred and ninety-five nit mutants were obtained from 47 isolates of various pathotypes of the fungus collected from different regions, host cultivars and years. In complementation tests, 45 VCGs were identified. Eighteen RAPD primers were employed in the molecular analyses, producing 111 polymorphic bands. Estimates of genetic similarities, determined from the Sorence-Dice coefficient, ranged from 0.42 to 0.97; the dendrogram obtained by cluster analysis revealed 18 groups of isolates. RAPD and VCG markers presented high genotypic diversity. The number of significant associations (P = 0.05) between RAPD, VCG and pathogenicity markers ranged from 0 (VCG) to 80% (pathogenicity). The test of multilocus association (r(d)) for RAPD markers was significantly different from zero (P < 0.001), suggesting linkage disequilibrium. However, the results for VCG markers show the presence of recombination mechanisms. In conclusion, RAPD markers and VCGs were useful for detecting genetic variability among isolates of C. lindemuthianum. We found considerable diversity among isolates from the same geographic origin within a short interval; this suggests rapid evolution. There is a need for further studies to elucidate the population structure of this pathogen in agro-ecosystems.