Trichoderma root colonization dynamics and their correlation with phosphorus mobilization in tropical soils

Abstract

Somewhere between the soil particle and the root surface lies a biological battlefield where microorganisms compete for carbon and nutrients and Trichoderma species are among the most effective colonizers. This research investigated root colonization dynamics of four Trichoderma species (T. harzianum, T. viride, T. asperellum, T. koningii) and a consortium of all four on mung bean (Vigna radiata L.) in a tropical Fluvisol at Bangladesh Agricultural University, Mymensingh, during the 2022-2023 kharif season. T. asperellum achieved the highest individual colonization rate (56.8%), while the consortium reached 63.2%. Root colonization correlated strongly with rhizosphere acid phosphatase activity (r = 0.87) and phosphorus solubilization (r = 0.81). The consortium treatment increased available soil P by 34.1 mg kg⁻¹ and grain yield by 38.7% over the uninoculated control. These findings show that multi-species Trichoderma inoculation can serve as a biological alternative for phosphorus management in tropical legume systems.