Morphological, phylogenetic and pathogenicity characterisation of Fusarium species associated with wilt disease of pumpkin (Cucurbita pepo Linnaeus

Fusariumis a well-known soil-borne fungus where most species belonged in this genus is prominently phytopathogenic. Nevertheless, this pathogenic species has affected the production of pumpkin worldwide. This study underlines the morphological, phylogeny and pathogenicity characteristics of Fusariumfor a better disease-control strategy. Twenty-six Fusariumisolates were collected from wilt infected pumpkin in various locations of Peninsular Malaysia. From the combinations of morphological and molecular identifications, four species were identified as F. oxysporum(2 isolates), F. solani(4 isolates), F. proliferatum(7 isolates) and F. incarnatum(13 isolates). Microscopic and macroscopic observation visualized distinct characteristics of the identified Fusariumspecies. Sequence analyses of tef1αand β-tubgenes inferred by maximum likelihood tree resulted in distinctsection-specific characteristics. Meanwhile, pathogenicity test of Fusariumisolates presented by the seed inoculation produced various degrees of severities. Fusarium solaniC2526P recorded the highest severity of 93.8% after 30 days of post inoculation (dpi). Symptoms have been identified as early as 10 dpi producing stunted growth of the plants. On the other hand, Fusarium oxysporumD2532P recorded 85.3% disease severity. Pathogenic Fusariumcaused stunted growth, chlorosis, wilting and necrosis especially at the root of pumpkin plants. This study provides valuable information and methods to manage wilt infected pumpkin in the future.