Antagonistic potential of Trichoderma erinaceum and Trichoderma asperelloides to gray stem rot corn

Stem rot is among the main diseases that affect corn stalks, compromising the translocation of water and nutrients, resulting in a reduction in grain filling and, at the end of the cycle, causing plants to lodge. In Brazil, this disease has a high incidence in both soybean and corn producing regions. It has been difficult to control due to the wide range of hosts it affects, production of survival structures and the absence of chemical products registered in the country for control. Based on this and growing adoption of microbiological products for controlling plant diseases, this study sought to select and identify Trichoderma isolates with potential antagonistic action against Macrophomina species that cause gray stem rot. Initially, 19 isolates from soybean and corn producing regions were identified as Macrophomina phaseolina . An isolate of Macrophomina pseudophaseolina was added to perform in vitro antagonism tests. In these tests, three Trichoderma isolates were selected in the pairing tests, volatile organic compounds tests, and non-volatile organic compounds tests as well as in the in vivo biocontrol test where both the Trichoderma erinaceum isolates and the T. asperelloides isolates. Therefore, this study contributes important information for the use of T. erinaceum and T. asperelloides in the biocontrol of diseases caused by Macrophomina spp. in maize.