Estimation of Solubilization of Tricalcium Phosphate by Trichoderma spp. Isolated From Citrus Aurantium Roots

Abstract

The ability of eleven Trichoderma isolates obtained from the roots of Citrus aurantium in the Gharb region of Morocco to solubilize tricalcium phosphate was evaluated in vitro using the medium NBRIP with added Ca3(PO4)2.After 5 days of incubation on the agar medium, the colonies of all isolates reached their maximum diameter of 90 mm.In addition, after 7 days, isolates T-RB-3,T-RB-9;T-RB-5 have been able to produce a large number of conidia with respective concentrations of 34; 40, and 55 conidies.mm-2 whereas for the others sporulation was low to 0. In the liquid medium, a simultaneous increase in the soluble phosphorus concentration was recorded in the culture filtrates of the different Trichoderma isolates as a function of incubation time.Peak concentrations are observed on day 7 in cultures of isolates T-RB-3,T-RB-5,T-RB-8,T-RB-9T-RB-10, andT-RB-11, reaching a maximum value of14.33 μg.mL-1relative to white (0.48 μg.mL-1). PH values decreased to 4.38 in T-RB-2 from control (6.12).On day9,The highest value of fresh,dry weights, and soluble phosphorus were recorded in isolatesT-RB-3