Evaluación in vitro de la actividad de Trichoderma spp. sobre Fusarium spp. como alternativa al uso de fungicidas químicos que producen contaminación ambiental en la florícola Happines Flowers.

Abstract

The purpose of this research is to evaluate in vitro the efficacy of Trichoderma spp. use as a method of biological control of Fusarium spp. in the cultivation of carnation (Dianthus caryophyllus) of Happines Flowers Growing. From soil samples and plant material, it go to isolate in medium of crop Agar Potato Dextrose (PDA) and identify macroscopic and microscopic only a strain of Trichoderma (Trichoderma harzianum) and two strains of Fusarium (Fusarium redolens and Fusarium oxysporum), causing vascular wilting in carnation plants. For the analysis of the antagonism between both genders three methods that determined the percentage of inhibition were applied. By dual method Trichoderma harzianum produced inhibition percentages of 20.3% for Fusarium redolens and 26.9% Fusarium oxysporum, whereas the method of volatilized compounds obtained a 35.23% and 27.5% respectively. By the method of inverted discs there was no growth so it could not assess the percentage of inhibition. In compatibility tests between different Trichoderma harzianum and different chemicals compounds used, a strong inhibition of mycelial growth was observed compared with fungicides carbendazim, pentacloronitrobenzeno and acaricide profenofos. The fungicides carboxin + captan, mancozeb and chlorothalonil, and insecticides thiodicarb and dicofol + tetradifom, were slightly compatible with this species. Insecticides and/or acaricides acetamiprid, methamidofos and fipronil showed greater compatibility and with this biological control agent, causing only some variations in appearance. For Fusarium spp. fungicides having a higher inhibitory activity are: carbendazim, pentacloronitrobenzeno and carboxin + and captan. Because Trichoderma harzianum is not able by itself to control the growth of Fusarium spp. and that only carboxin + captan let the growth of Trichoderma harzianum and inhibits the one of Fusarium spp., for the control of these pathogens recommended a treat combined of carboxin + captan to low doses and inoculation of Trichoderma harzianum, for the correct development of this combined treat it y should delete the use of profenofos, substituting it by acetamiprid or fipronil.