Chromosome constitution of hybrid strains constructed by protoplast fusion between the tomato and strawberry pathotypes of Alternaria alternata

Yasunori Akagi, Masatoki Taga, Mikihiro Yamamoto, Takashi Tsuge, Yukitaka Fukumasa-Nakai, Hiroshi Otani, Motoichiro Kodama

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

To analyze the genetics of host-specific toxin production and its relation to the specific pathogenicity of a mitosporic fungus Alternaria alternata, we developed a protoplast fusion system. Protoplasts of drug-resistant transformants of the A. alternata tomato pathotype (AAL-toxin producer) and A. alternata strawberry pathotype (AF-toxin producer) were fused by electrofusion. Of five fusion strains examined, two strains were pathogenic on both tomato and strawberry host plants, whereas the rest of the fusion strains were pathogenic only on tomato. Pulsed-field gel electrophoresis analysis demonstrated that the hybrid strains pathogenic on both tomato and strawberry carry 1.0- and 1.05-Mb conditionally dispensable (CD) chromosomes derived, respectively, from the parental strains of the tomato and strawberry pathotypes. On the other hand, the fusion strains appeared to maintain only a single homologous chromosome derived from one of the parental strain in the case of essential chromosomes (A chromosomes). The results suggest that fusion strains between two different pathotypes of A. alternata might be haploid resulting from the deletion of extra sets of essential chromosomes in the fused nuclei, whereas the CD chromosomes derived from each parental strain could be maintained stably in a new genetic background with an expanded range of pathogenicity.

Original languageEnglish
Pages (from-to)101-109
Number of pages9
JournalJournal of General Plant Pathology
Volume75
Issue number2
DOIs
Publication statusPublished - Apr 2009

Keywords

  • AAL-toxin
  • AF-toxin
  • Alternaria alternata
  • Host-specific toxin
  • Protoplast fusion

ASJC Scopus subject areas

  • Agronomy and Crop Science
  • Plant Science

Fingerprint Dive into the research topics of 'Chromosome constitution of hybrid strains constructed by protoplast fusion between the tomato and strawberry pathotypes of Alternaria alternata'. Together they form a unique fingerprint.

  • Cite this