Joint Influence of Pratylenchus penetrans (Nematoda) and Glomus fasciculatum (Phycomyceta) on the Ontogeny of Phaseolus vulgaris
Keywords: Root-Lesion Nematode, Dry Beans, Vesicular-Arbuscular Mycorrhizae
AbstractThe joint influence of Pratylenchus penetrans and Glomus fasciculatum on the ontogeny of Phaseolus vulgaris (navy beans) was examined under greenhouse conditions. Root colonization by G. fasciculatum was less in the presence of P. penetrans than in its absence. Population densities of P. penetrans were initially (prior to 600 cumulative degree days at a base of 10C [DD]) lower in plants exposed to only P penetrans than in plants grown in the presence of both organisms. After 600 DD, nematode population densities were greater in plants exposed to both P. penetrans and G. fasciculatum than in those grown only in the presence of the nematode. In addition, the reproductive rate of G. fasciculatum was reduced in the presence of P. penetrans. Plant growth and yield were reduced in the presence of P. penetrans, and increased in the presence of G. fasciculatum.