The effect of the fungicides two Vitaflo, Topsin-M and the fungus Trichoderma harzianum Rifai in inhibiting the growth of some fungi isolated from wheat grains prepared for planting

Abstract

This research aimed to study the compatibility of the fungicides Vitaflo (Carboxin+Thiram) and Topsin-m (Thiophanate methyl) with the fungus Trichoderma harzianum Rifai (1969) or fungal filtrate in inhibiting the growth of some fungi isolated from wheat grains prepared for cultivation. The research was carried out in 2025 in the Pesticide Research Laboratory of the Plant Protection Department, Faculty of Agricultural Engineering, Damascus University, Syria.

The medium poisoning method was used to study the effect of the fungicides at half, recommended and double concentrations in inhibiting the growth of the fungi T. harzianum, F.culmorum, Aspergillus niger and Alternaria sp,  and filtrate at concentrations of 5, 10 and 15% on the fungi isolated from wheat. The double culture method compared T. harzianum with the tested fungi. The results showed that the effect of fungicides on inhibiting T. harzianum growth in PDA varied according to the chemical composition, concentrations used and time after incubation. It was found that Vitaflo gave the highest inhibition rates of fungal growth compared to Topsin-M at all concentrations and tested periods. Vitaflo provided the highest inhibition rates for fungal growth compared to Topsin-M at all concentrations and tested periods. The growth-inhibiting effect of both fungicides increased with increasing concentration, while the effect decreased with the duration of

preparation. The inhibition rate at the recommended concentration reached 28.24% and 15.29% for both Vitaflo and Topsin-M after 6 days of incubation. The data also showed that the effect of the tested fungicides, fungal filtrate, and T. harzianum fungi varied in inhibiting the tested fungi F.culmorum, Aspergillus niger and Alternaria sp. The effect increased with increasing concentration. Alternaria sp. was the least sensitive fungus to fungicides, and  Aspergillus niger was the most sensitive to the fungicides. The results showed that combining the fungicides at half concentration with the filtrate at 10% concentration or T. harzianum fungi gave the highest effect in inhibiting the tested fungi compared to the separate treatments. As a result, the tested fungicides can be combined with the fungus or fungal filtrate and incorporated into integrated fungal control after field trials.