Glomus fasciculatum, a Weak Pathogen of Heterodera glycines
Francl, L.J.; Dropkin, V.H.
Journal of Nematology 17(4): 470-475
1985
ISSN/ISBN: 0022-300X PMID: 19294126 Document Number: 251654
The occurrence of chlamydospores of G. fasciculatum (Gf) within cysts of H. glycines, and the effects of vesicular-arbuscular mycorrhizae on nematode population dynamics and soyabean plant growth were investigated. Chlamydospores occupied 1-24% of cysts recovered from field soil samples. Hyphae of Missouri isolate Gf1 penetrated the female nematode cuticle shortly after she ruptured the root epidermis. Convoluted hyphae filled infected eggs, and sporogenesis occurred within infected eggs. G. microcarpum, G. mosseae and 2 isolates of Gf were inoculated with H. glycines on plants of 'Essex' soyabeans. Each of the 2 Gf isolates infected about 1% of the nematode eggs in experimental pot cultures. The Gf1 isolate decreased the number of first-generation adult females by 26%, compared with nonmycorrhizal control. The total numbers of first-generation plus 2nd-generation adult females were similar for both Gf isolates and 29-41% greater than the nonmycorrhizal control. Soyabean plants with Gf and H. glycines produced more biomass than did nonmycorrhizal plants with nematode, but only Gf1 delayed leaf senescence.