Epsilon Archive for Student Projects

Abstract

Potato is one of the most important staple crops worldwide. Potato productivity is severely threatened by pathogens such as Alternaria solani (early blight), Phytophthora infestans (late blight), and Rhizoctonia solani (black scurf). Chemical control is the dominant management strategy for these diseases, but it is unsustainable due to the development of fungicide-resistant pathogens, environmental risks, and economic costs. This study evaluated the effectiveness of Pythium oligandrum as a biological control agent through in vitro and in planta experiments. According to the results, P. oligandrum significantly inhibited both A. solani and P. infestans growth when co-inoculated. Dual culture assays of P. oligandrum and R. solani demonstrated strain-specific susceptibility through strong inhibition of AG3 but limited inhibition of AG5. Mycoparasitic interactions of P. oligandrum against R. solani, including hyphal coiling observed in microscopy. In planta trials, the ‘Desiree’ cultivar showed that foliar application of P. oligandrum reduced early blight lesion development rather than soil application. No significant suppression was observed in ‘Kuras’ due to its physiological stress by edema. Collectively, these findings indicate the possibility of P. oligandrum as a sustainable strategy in Integrated Pest Management (IPM) frameworks. Further research on application amounts and time periods, strain compatibility, and host–pathogen–biocontrol interactions will be essential for resilient and environmentally sound production systems.