Characterization of Pathogenic Fungi Infecting Citrullus lanatus in Different Agroecological Regions of Embu County, Kenya

Abstract: Watermelon (Citrullus lanatus) fruit is nutritious and a profitable cash crop. Its production in Kenya however has dropped from 379.36K metric tonnes to 173.70K metric tonnes in the last five years; attributed to pests, diseases and unpredictable climatic conditions. Study done between July and November, 2018 isolated and characterized fungi associated with watermelon determining their diversity and occurence frequency in Embu County, Kenya. Necrotic fruits and leaves (n=160) were sampled from random farms (n=16). Fungi isolated and  cultured on PDA.; characterized by morphological and molecular method. ANOVA was used to detect fungal prevalence differences among sites. Fusarium oxysporum was most prevelent with 73% frequency, Aspergillus niger (32%). Penicilliun crustosum and Fusarium brachygibbosum at 31%  each. Least prevalent was Trichoderma asperellum (1%). Significant differences (F= 23.365, p=0.05, df=13), were observed among agroecological sites except for Fusarium oxysporium and F. brachygibbosum. Majority of fungi identified were of significant economic importance.