Interactions Between a Vesicular-Arbuscular Mycorrhizal Fungus and Root-Knot Nematode on Soybean

Publisher Website
Google Scholar
Abstract
In greenhouse tests, roots of cultivar Pickett soybean [Glycine max] plants were inoculated with chlamydospores of Glomus macrocarpus and/or eggs of Meloidogyne incognita by using an aluminum foil funnel technique. Soybeans were inoculated with 1 organism 10 days prior to the 2nd organism or with both organisms simultaneously either at or 10 days after planting. After 14 wk, plants which were infected with both organisms had significantly fewer galls per gram of root, greater root weights and higher yields than did those infected with the nematode alone. Chlamydospore production and percentage of mycorrhizal roots were not significantly different in the presence or absence of nematodes. Atypical hyphae, vesicles and arbuscules of the fungus were observed in galled tissue and 57% of the galls examined were not associated with mycorrhizal roots. With the level of nematode inoculum used in these tests, the presence of G. macrocarpus reduced the number of galls produced by M. incognita; the presence of the nematode affected mycorrhizal development in the immediate area of the gall, but had little effect on the mean percentage of mycorrhizal roots or the number of chlamydospores produced by the fungus.