Novel green formulation of Trichoderma asperellum as an effective field antiviral candidate for sustainable eco-friendly management of potato virus Y
Abstract
Potato virus Y (PVY) is the most destructive virus affecting potato plants and ranks the fifth most economically significant plant virus worldwide. It continues to pose a serious threat to global potato production. This study aimed to develop a Trichoderma-based bioformulation for combating PVY under field conditions. Formulating biocontrol agents offers multiple advantages, including enhanced sustainability, improved efficacy, and ease of application. Screening experiments identified formula No. 6 (79 ml TCF + 18 ml garlic oil) as exhibiting the highest anti-PVY activity; thus, it was selected for further evaluation of its protective and post-inoculation suppressive effects under both growth chamber and open field conditions. In the growth chamber experiment, qPCR analysis revealed that treatment C3 (20 ml L−1) outperformed C1 (5 ml L−1) and C2 (10 ml L−1) in both protective and post-inoculation applications, reducing PVY content by 100% and 78.33% (protective) and 89.92% and 75.66% (post-inoculation) relative to the PVY-infected control at 21 and 42 dpi, respectively. Additionally, C3 treatment markedly upregulated PR1-b gene expression and increased total phenol and flavonoid contents. In open field trials, the C3 treatment effectively protected and reduced the PVY content in the treated PVY-infected potato plants by 92% (post-inoculation double spray), 86% (protective), and 72% (post-inoculation single spray) compared with the PVY-infected control. The post-inoculation (double spray) treatment significantly reduced disease incidence and severity by 60.26% and 70.10%, respectively. In addition, this treatment significantly improved plant growth parameters compared with the PVY-infected control, resulting in increases of 19.45% in chlorophyll content, 30.23% in fresh weight, and 90.50% in dry weight. These findings suggest that the formulation is a promising candidate for sustainable PVY management, although further validation is needed before commercial application. The developed product has been submitted to the Egyptian Patent Office.