Recovery of Mutants Impaired in Pathogenicity After Transposition ofImpalainFusarium oxysporumf. sp.melonis

• DOI: 10.1094/phyto.2000.90.11.1279
• Publication Date: 2007-05-11T11:02:31Z
• Authors: Quirico Migheli; Christian Steinberg; Jean-Michel Davière; Chantal Olivain; Catherine Gerlinger; Nadine Gautheron; Claude Alabouvette; Marie-Josée Daboussi
• Keywords: Transposon mutagenesis; Transposition (logic); Insertional mutagenesis

The ability of transposon impala to inactivate genes involved in pathogenicity was tested Fusarium oxysporum f. sp. melonis. Somatic excision an copy inserted the nitrate reductase-encoding niaD gene positively selected through a phenotypic assay based on restoration reductase activity. Independent events were analyzed molecularly and shown carry reinsertedimpala more than 70% cases. Mapping reinserted elements large NotI-restriction fragments showed that transposes randomly. By screening 746 revertants plants, high proportion (3.5%) mutants impaired their pathogenic potential recovered. According kinetics wilt symptom development, strains clustered three classes: class 1 grouped two never induced symptoms host plant; 2 3 15 9 which caused 50 30 days after inoculation, respectively. first results demonstrate efficiency transposition generating affected pathogenicity, are usually difficult obtain by classical mutagenesis, open possibility clone altered with as tag.