墨西哥中部致病疫霉单倍型I-b的首次报道

First Report of Haplotype I-b of Phytophthora infestans in Central Mexico.

作者信息

Garay-Serrano E, Fernández-Pavía S P, Rodríguez-Alvarado G, Flier W G, Lozoya-Saldaña H, Rojas-Martínez R I, Goss E M, Grünwald N J

机构信息

Instituto de Investigaciones Agropecuarias y Forestales, UMSNH, Tarímbaro, Michoacán, México.

Plant Research International, Wageningen, the Netherlands.

出版信息

Plant Dis. 2007 Jul;91(7):909. doi: 10.1094/PDIS-91-7-0909B.

DOI:10.1094/PDIS-91-7-0909B

PMID:30780417

Abstract

Central Mexico is considered a center of genetic diversity for Phytophthora infestans on the basis of a range of genotypic and phenotypic characteristics (3). Surprisingly, while mitochondrial DNA (mtDNA) haplotypes I-a, II-a, and II-b have been reported from central Mexico, haplotype I-b has not been found in central Mexico (1). Therefore, a more extensive search for haplotypes was conducted in areas where sexual reproduction occurs. During the summer of 2003, leaflets of cvs. Rosita and Tollocan with a single lesion of late blight were collected in the area of Villarreal, located in Terrenate County in Tlaxcala, Mexico (170 km northeast of Mexico City). Fourteen P. infestans isolates were characterized for mtDNA haplotype, isozyme genotype (glucose 6- phosphate isomerase [Gpi] and peptidase [Pep]), and mating type. Isolation, mating type, and isozyme genotype were characterized following reported protocols (1,4). MtDNA haplotype was determined by amplifying and digesting the P2 and P4 regions and comparing amplicons to those of reference strains of known haplotype (1,2). Twelve isolates were mtDNA haplotype I-a and two were I-b. While the mtDNA I-b has been associated with the US-1 lineage (mating type: A1, Gpi: 86/100, Pep: 92/100), the genotypes for the Mexican isolates were A2, 86/100 Gpi, 100/100 Pep from cv. Rosita and A2, 86/100 Gpi, 92/100 Pep from cv. Tollocan. To our knowledge, this is the first report of the I-b mtDNA haplotype of P. infestans from central Mexico and it is now clear that all four haplotypes exist in Mexico. This finding therefore, stresses the importance of including a representative regional sampling of Mexican and Andean isolates in studies inferring the origin of this species. References: (1) W. G. Flier et al. Phytopathology 93:382, 2003. (2) G. W. Griffith and D. S. Shaw. Appl. Environ. Microbiol. 64:4007, 1998. (3) N. J. Grünwald and W. G. Flier. Ann. Rev. Phytopathol. 43:171, 2005. (4) N. J. Grünwald et al. Phytopathology 91:882, 2001.

摘要

基于一系列基因型和表型特征，墨西哥中部被认为是致病疫霉的遗传多样性中心（3）。令人惊讶的是，虽然在墨西哥中部已报道有线粒体DNA（mtDNA）单倍型I-a、II-a和II-b，但尚未在墨西哥中部发现单倍型I-b（1）。因此，在有性生殖发生的地区对单倍型进行了更广泛的搜索。2003年夏季，在位于墨西哥特拉斯卡拉州特雷诺特县的比利亚雷亚尔地区（墨西哥城东北170公里处）收集了带有晚疫病单个病斑的罗西塔和托洛坎品种的小叶。对14个致病疫霉分离株进行了mtDNA单倍型、同工酶基因型（葡萄糖6-磷酸异构酶[Gpi]和肽酶[Pep]）及交配型的鉴定。按照已报道的方案（1,4）对分离、交配型和同工酶基因型进行了鉴定。通过扩增和消化P2和P4区域并将扩增子与已知单倍型的参考菌株的扩增子进行比较来确定mtDNA单倍型（1,2）。12个分离株为mtDNA单倍型I-a，2个为I-b。虽然mtDNA I-b与US-1谱系相关（交配型：A1，Gpi：86/100，Pep：92/100），但来自罗西塔品种的墨西哥分离株的基因型为A2，86/100 Gpi，100/100 Pep，来自托洛坎品种的为A2，86/100 Gpi，92/100 Pep。据我们所知，这是墨西哥中部致病疫霉I-b mtDNA单倍型的首次报道，现在很清楚墨西哥存在所有四种单倍型。因此，这一发现强调了在推断该物种起源的研究中纳入墨西哥和安第斯分离株的代表性区域样本的重要性。参考文献：（1）W.G.弗利尔等人，《植物病理学》93:382，2003年。（2）G.W.格里菲思和D.S.肖，《应用与环境微生物学》64:4007，1998年。（3）N.J.格伦瓦尔德和W.G.弗利尔，《植物病理学年度评论》43:171，2005年。（4）N.J.格伦瓦尔德等人，《植物病理学》91:882，2001年。