Control of strawberry gray mold fungus with combined application of different species of Trichoderma and salicylic acid

The rot caused by strawberry gray mold (Botrytis cinerea) is one of the most important rots causing damage in the field and market. The purpose of this research is that biological control agents and compounds inducing plant defense reactions seem to lead to a reduction in the frequency of spraying or not spraying fungicide compounds on the crop.

Different isolates of B. cinerea were collected from greenhouses and farms in Kurdistan province, and their morphological and molecular characteristics were determined. In the following, different concentrations of salicylic acid (SA) either individually or in combination with different Trichoderma species were investigated in the laboratory and greenhouse on strawberry gray mold.

In the comparison of averages, the highest percentage of inhibition in the cross-culture between Trichoderma spp and Botrytis sp. is related to T. orientalis (60.82%), the highest percentage of inhibition of the extracellular secretions of Trichoderma isolates on the growth of Botrytis in each two concentrations of 15 and 30% related to T. ceramicum was 85.57% and the effect of volatile compounds of different Trichoderma species on the growth of B. cinerea showed that the highest percentage of inhibition was related to the treatment of T. asperellum isolate with 63.70%. Investigating the effect of salicylic acid in preventing the mycelium growth of botrytis fungus in the laboratory showed that with increasing concentration of salicylic acid from 1 to 2 millimolar, the inhibition percentage of Botrytis cinera increased to 61%.

The results of the experiment showed that the use of some Trichoderma species along with salicylic acid increases the resistance and control of strawberry to gray mold disease in the field and laboratory.