Phylogeography and Molecular Species Delimitation of Pratylenchus capsici n. sp., a New Root-Lesion Nematode in Israel on Pepper (Capsicum annuum).

ABSTRACT

Root-lesion nematodes of the genus Pratylenchus parasitize the roots of numerous plants and can cause severe damage and yield loss. Here, we report on a new species, Pratylenchus capsici n. sp., from the Arava rift, Israel, which was characterized by integrative methods, including detailed morphology, molecular phylogeny, population genetics, and phylogeography. This species is widely spread across the Arava rift, causing significant infection in pepper (Capsicum annuum) roots and inhibiting plant growth. Both morphological and molecular species delimitation support the recovered species as a new species. We found high cytochrome oxidase subunit I haplotype diversity, and phylogeography analysis suggests that contemporary gene flow is prevented among different agricultural farms, while population dispersal from weeds (Chenopodium album and Sonchus oleraceus) to pepper occurs on a relatively small scale. Our results suggest that weeds are an important reservoir for the dispersal of P. capsici n. sp., either as the original nematode source or at least in maintaining the population between growing seasons.