Plant crop yield enhancement potentials of three indigenous arbuscular mycorrhizal fungi isolated from Ile-Ife, Southwest Nigeria

Food security in developing countries still remains a global concern requiring effective and sustainable solutions. This study investigated the effect of three indigenous arbuscular mycorrhiza (AM) fungal inocula namely; Funneliformis mosseae, Claroideoglomus luteum and Glomus viscosum on the growth and yield of a tomato cultivar (Lycopersicum sp.). The spores of the fungi were isolated from a fallow land in Ile-Ife, Nigeria and were propagated separately by maize pot culture. The obtained pure culture spores were used to infect tomato seedlings singly and in different combinations in a sterile soil culture. A control un-inoculated treatment consisted of sterile soil only. There were variations in the extent at which pots inoculated with AM inocula improved plant growth rate, fruit yield and fruit size after harvest. For the single inoculation treatments, Funneliformis mosseae had the best gross fresh fruit weight/pot (191.47 g), mean fruit weight (27.35 g), mean fruit size (85.47 cm2) and gross fruit weight per plant (68.83 g); the worst was G. viscosum which had gross fresh fruit weight/pot (191.47 g), mean fruit weight (27.35 g), mean fruit size (85.47 cm2) and gross fruit weight per plant (68.83 g). However, not all combinations of the AM inocula were effective in improving plant crop yield. The best combined AM species treatment (Funneliformis mosseae _Claroideoglomus luteum) had mean fruit weight (22.54 g) and mean fruit size (88.43 cm2), while F. mosseae_C. luteum_G. viscosum combination had the least mean fruit weight (9.33 g) and mean fruit size (51.28 cm2). On the other hand, the combination treatments were generally better in post-harvest residual spore yield in the soil than the single treatments. There was no association between fruit yield and residual spore densities. This study has shown that these indigenous AM inoculants have the potentials to individually enhance fruit yield compared to the simulated background combined effect was found in the fallow land. We conclude that adequate knowledge of AM interactions with their host plants will be required for proper composition of AM fungi inocula for optimal application in agriculture to enhance plant crop yield.