Entomopathogen Metarhizium anisopliae Promotes the Early Development of Peanut Root

The benefit of the entomopathogen Metarhizium anisopliae to early root development was evaluated. Two inoculating methods, conidia-suspension-drenching (T-1) and conidia-coating (T-2), were used when sowing peanut. The results showed that taproot length and lateral root number in T-1 significantly increased compared to the control (T-0) in days 4-10 after treatment, whereas no significant difference was found between T-2 and T-0. The fungal density by T-1 and T-2 fluctuated in the first 8 days, followed by a gradual decline. The ratio of the taproot length or lateral root number in T-1 and T-0 was significant relative to the fungal persistence. It suggested that M. anisopliae promotes peanut root development and should be considered as important factor in plant protection besides pest controls.