Importancia del aislamiento y del rango de concentracion de conidias en el efecto de Trichoderma asperellum sobre el crecimiento de plantulas de Solanum lycopersicum L

Longitudinal growth of shoot and roots was investigated in tomato seedlings (Solanum lycopersicum L) after application of four isolates of T. asperellum (T25, T46, T84 y T109). Only the isolate T109 caused a significant (p ≤ 0.05) increase of longitudinal growth of roots and shoots, and dry weight of seedlings was also stimulated from the first week after T109 application. The growth was significantly (p ≤ 0.05) stimulated by 105 and 106 conidia/ml, but it was not by 104, 107 and 108 conidia/ml. These results indicate that growth stimulus caused by T. asperellum in tomato seedlings, occurs only with specific isolates and at a specific concentration ranges.