Impact of arbuscular mycorrhizal fungi, Trichoderma viride and Pseudomonas fluorescens on the growth enhancement of Vitex negundo

In the present investigation a pot experiment with sixteen different combinations of Glomus mosseae (G), Acaulospora laevis (A), Trichoderma viride (T) and Pseudomonas fluorescens (P) was carried out to assess the interaction between bioinoculants and their consequent effect on the growth and nutrition of Vitex negundo a medicinal plant. The result obtained indicated the dependence of Vitex negundo, on mycorrhizal symbiosis. The different growth parameters increased significantly after 120 days of inoculation in comparison to control. Among all the growth parameters plant height (85.1±2.50), fresh shoot weight (21.6±0.57), dry shoot weight (16.0±0.51), fresh root weight (24.2±0.69), dry root weight (15.1±0.54), root length (40.2±1.67), leaf area (29.0±0.35), spore count number (78.4±5.55), percent root colonization (92.6±1.48), total chlorophyll content (2.055±0.003), phosphorus contents in roots (0.406±0.003) and shoots (0.243±0.005) were highest in combination of G. mosseae + A. laevis + T. viride + P. fluorescens. These results indicate that combined inoculation with two native AMF isolates (G. mosseae and A. laevis), T. viride and P. fluorescens significantly increased growth and other parameters. Thus, the improvement in plant growth could be attributed to the enhancement of nutrients via an increase in the absorbing root surface area due to mycorrhizal symbiosis.