Growth Characteristics of Fusarium Spp. Causing Wilt Disease in Psidium Guajava L. in India

Abstract

Fusarium oxysporum f. sp. psidii and F. solani, causal agents of wilt in guava are highly variable pathogens. This study was conducted on cultural and physiological (temperature and pH) characters. The data revealed that maximum mycelial growth was obtained in potato dextrose agar as semi-solid media i.e. 78.00 mm for F. oxysporum f. sp. psidii; 73. 83 mm for F. solani, while malt extract broth as liquid broth media i.e. 1 385 mg mycelia for F. oxysporum f. sp. psidii; 1491 mg for F. solani. Maximum sporulation was recorded in oatmeal agar and mycological broth. The optimum temperature and pH for growth of both Fusarium spp. isolates was 28C and 5.5. The isolates differed in their colony growth; mycelial mass, macro-conidia, and micro-conidia produced. These variations were characters of each of the isolates with respect to cultural and physiological characters.