Identification of sources of resistance to Fusarium oxysporum in Physalis sp. genotypes.

Abstract

The resistance of Cape gooseberry to Fusarium oxysporum was evaluated in 70 accessions of Physalis peruviana and related taxa (P. philadelphica, P. ixocarpa, P. floridana, P. pubescens, P. angulata, P. pruinosa, P. viscosa, P. mexicana, Nicandra physalodes, and Solanum auriculatum). These accessions were obtained from different national and international collections, including accessions from the Colombian productive sector. These represented wild materials, commercial cultivars, native and foreign weeds, and commercial ecotypes from the main producing countries: Colombia, South Africa, Kenya, and Peru. The evaluation of resistance to F. oxysporum was carried out under greenhouse conditions using the most aggressive strain supplied by the Fusarium collection maintained by the molecular microbiology laboratory of the Center for Biotechnology and Bioindustry (CBB), currently in charge of the Working Collection of Microorganisms of Agrosavia, which was isolated from infected fields. The symptoms were monitored using a severity scale, containing 10 degrees and five categories. Data information obtained from daily evaluations was analyzed through a severity evaluation and different statistical analyses. The results identified one accession belonging to Physalis peruviana and two related taxa (Physalis floridana and Solanum auriculatum) as resistant to this pathogen. These accessions could be directly used in breeding programs, either as improved cultivars or as race-specific resistance donors for other Physalis peruviana genotypes.

Keywords

• fungi disease
• induced resistance
• phytogenetic
• plant breeding
• vascular wilt