Evaluation of phosphodissolvent IAA producing strains of Trichoderma, spp. through biometric response of Phaseolus vulgaris L
By: Dorcas Zúñiga-Silgado, León Darío Vélez Vargas
Key Words: Trichoderma sp., phosphodissolution, IAA production, Phaseolus vulgaris L.
Int. J. Biosci. 8(6), 103-118, June 2016.
Studies report that in addition to biocontrol effects, Trichoderma spp., exhibit phosphodissolvent and indole acetic acid (IAA) production capacities. In greenhouse laboratory conditions, the effects of four native strains of Trichoderma spp., were evaluated on the germination and growth of beans. Inoculants of each strain were prepared in concentrations of 104, 106, and 108 spores mL-1, which were then used to inoculate bean seeds and seedlings. The biometric variables evaluated were number of germinated seeds, germination percentage, germination velocity index, and median germination time. Later, germinated seeds were taken to greenhouse conditions and over the course of 90 days, height of seedlings, circumference of stalks, number of leaves, length of roots, number and mass of fruits, and overall dry mass were measured. The TRIC13 strain, with concentrations of 7 x 108 spores mL-1 , showed better results than the rest of the strains evaluated with respect to seed germination. However, in relation to growth and germination of bean plants, concentrations of 7 x 104 spores mL-1 were more efficient in all treatments evaluated. Considering the biometric variables evaluated, the study showed an ability of strains of Trichoderma to promote the growth and efficacy of greenhouse bean plants.