Interaction of Glomus species and Vigna unguiculata in an oxisol subjected to simulated erosion.

Abstract

An experiment was conducted in the greenhouse to determine the effectiveness of three species of vesicular-arbuscular (VA) mycorrhizal fungi in an oxisol subjected to simulated erosion using cowpea [Vigtta unguiculata (L.) Walp, cv.'California Black Eye'] as an indicator host. Inoculation of the eroded soil resulted in increased VA mycorrhizal colonization of roots without enhancing shoot P concentration and dry matter yields. Inoculation of the uneroded soil, however, led to significant improvement in infection level as well as in symbiotic effectiveness. Based on the results of this study, it appears that the lack of expression of mycorrhizal effectivness in the eroded soil is a result of nutrient deficiency. The results thus suggest the importance of restoring lost nutrients before the benefits of VA mycorrhizal inoculation could be effectively exploited for a successful establishment of a mycorrhizal cowpea in eroded soils.