Genomic differences between the new Fusarium oxysporum f. sp. apii (Foa) race 4 on celery, the less virulent Foa races 2 and 3, and the avirulent on celery f. sp. coriandrii

BMC Genomics

Samuel Brinker¹  Hannah Haensel¹  Lynn Epstein¹  Sukhwinder Kaur¹  Quyen Anh Tran Pham²  Radwan Barakat³  Peter Henry⁴  Oleg Daugovish⁵ 

[1] Department of Plant Pathology, University of California, Davis, 95616-8680, California, USA;Department of Plant Pathology, University of California, Davis, 95616-8680, California, USA;Current address: Janssen Biopharma, Inc., 260 E Grand Ave., 94080, South San Francisco, CA, USA;Department of Plant Pathology, University of California, Davis, 95616-8680, California, USA;Department of Plant Production & Protection, College of Agriculture, Hebron University, Hebron, Palestine;Department of Plant Pathology, University of California, Davis, 95616-8680, California, USA;USDA-ARS, 1636 East Alisal St., 93905, Salinas, CA, USA;University of California Cooperative Extension, 669 County Square Drive, Suite 100, 93003, Ventura, CA, USA;

关键词: Apium graveolens;    Celery;    Cilantro;    Coriander;    Coriandrum sativum;    Differentially expressed genes;    Fusarium oxysporum;    Fusarium oxysporum;    Fusarium yellows;    Transposable elements;   

DOI  :  10.1186/s12864-020-07141-5

来源: Springer

【 摘 要 】

BackgroundMembers of the F. oxysporium species complex (FOSC) in the f. sp. apii (Foa) are pathogenic on celery and those in f. sp. coriandrii (Foci) are pathogenic on coriander (=cilantro). Foci was first reported in California in 2005; a new and highly aggressive race 4 of Foa was observed in 2013 in California. Preliminary evidence indicated that Foa can also cause disease on coriander, albeit are less virulent than Foci. Comparative genomics was used to investigate the evolutionary relationships between Foa race 4, Foa race 3, and the Foci, which are all in FOSC Clade 2, and Foa race 2, which is in FOSC Clade 3.ResultsA phylogenetic analysis of 2718 single-copy conserved genes and mitochondrial DNA sequence indicated that Foa races 3 and 4 and the Foci are monophyletic within FOSC Clade 2; these strains also are in a single somatic compatibility group. However, in the accessory genomes, the Foci versus Foa races 3 and 4 differ in multiple contigs. Based on significantly increased expression of Foa race 4 genes in planta vs. in vitro, we identified 23 putative effectors and 13 possible pathogenicity factors. PCR primers for diagnosis of either Foa race 2 or 4 and the Foci were identified. Finally, mixtures of conidia that were pre-stained with different fluorochromes indicated that Foa race 4 formed conidial anastomosis tubes (CATs) with Foci. Foa race 4 and Foa race 2, which are in different somatic compatibility groups, did not form CATs with each other.ConclusionsThere was no evidence that Foa race 2 was involved in the recent evolution of Foa race 4; Foa race 2 and 4 are CAT-incompatible. Although Foa races 3 and 4 and the Foci are closely related, there is no evidence that either Foci contributed to the evolution of Foa race 4, or that Foa race 4 was the recent recipient of a multi-gene chromosomal segment from another strain. However, horizontal chromosome transfer could account for the major difference in the accessory genomes of Foa race 4 and the Foci and for their differences in host range.

【 授权许可】

CC BY