Effect of the fungus Trichoderma sp. about germination of weed plants and forage grasses

Abstract

Grasses are a predominant element in livestock areas, around 50% of these areas are degraded or in the process of degradation, favoring the appearance of weeds. Brazilian pastures contain numerous weeds, the main ones being Paspalum virgatum L. and Sporobolus indicus (L.) R.Br.. With degradation and infestation, there is a need to reform pastures, products derived from the microorganism Trichoderma sp. used as it is a growth promoter, but its interactions with grasses are unknown. The objective of this work was to evaluate the effect of the fungus on germination (G) and on the germination speed index (IVG) of weeds and forage grasses. The experiment was carried out at the State University of Mato Grosso-UNEMAT, municipality of Alta Floresta, and the production of the inoculum of Trichoderma sp was divided into two stages, the second in Petri dishes in a completely randomized design, with three replications, with 50 seeds per plate, in a double factorial arrangement 4x9, where the main factors are forage grasses (Brachiaria brizantha cv. Marandu and Panicum maximum cv. Mombaça), and weeds (Paspalum virgatum L. (razor grass) and Sporobolus indicus ( L.) R.Br. (capim-capeta)), the secondary factor to the doses of Trichoderma sp. (0 (witness); 0.05; 0.09; 0.14; 0.18; 0.23; 0.27; 0.32; 0.37 in ml). In the in vitro experiment, there was a significant interaction for both variables analyzed, with the dose 0.14 mL being indicated for application to the Marandu seed, as long as the navalha grass weed is not present. Doses above 0.05 mL are not recommended in the presence of razor grass.