Effect of Temperature, Media and pH on Growth and Sporulation of Fusarium udum Causing Wilt of Pigeonpea Cajanus cajan (L.) Millsp

Abstract

Pigeon pea (Cajanus cajan) is an important legume crop worldwide, highly valued for its nutritional benefits, particularly its protein and vitamin content. However, the productivity of pigeon pea is often hindered by various abiotic and biotic stress factors. Fusarium wilt, caused by the soil-borne pathogen Fusarium udum, stands out as a critical biotic factor impacting pigeonpea production the disease significantly hampers yield by infecting the plant's vascular system, leading to severe wilting and eventual plant death. As the pathogen thrives in the soil, it poses a persistent challenge to crop health, resulting in considerable losses for farmers. To understand the optimal conditions for the growth of Fusarium udum, a laboratory experiment was conducted on the effects of different culture media, pH, and temperature on the pathogen's mycelial growth and sporulation. The study revealed that the Potato Dextrose Agar (PDA) and Czapek Dox Agar were particularly effective in supporting the growth and sporulation of the fungus. These media provide essential nutrients that facilitate the robust growth of fungal colonies. Furthermore, the optimal temperature range for mycelial growth and sporulation of Fusarium udum was found to be between 20-30°C. Additionally, the fungus exhibited maximum growth and sporulation at a pH range of 6 to 7, indicating a preference for slightly acidic to neutral conditions. Understanding these growth parameters is crucial for developing effective disease management strategies by manipulating factors like nutrition source, pH and temperature.