Abstract:
Fruit rot disease on watermelon has been detected in almost all country that growth it
commercially. The first visible symptom of fruit rot on watermelon was a soft circular
lesion on the surface of watermelon and can be seen in market and stall in Kuala
Terengganu and Kelantan. The infected fruit showed color changes from green to
purplish pigmentation on the watermelon skins. A total of 30 strains of Fusarium
species were isolated from fruit rot disease. For the identification of Fusarium
species, carnation leaves agar (CLA) and potato dextrose agar (PDA) medium were
used to observe the colony morphology, size and shapes of macroconidia and
microconidia. About 86.6% (26 isolates) were identified as F. solani, 10% (3 isolates)
as F. nygamai and 3.3% (1 isolates) as F. oxysporum. The in vitro and in vivo
experiments were done for antifungal studies and 15% of lime extraction was proven
to inhibit F. solani. For in vivo technique, the watermelon that wehich dipped into the
15% of lime extraction solution and than inoculated with F. solani can reduced the
weight loss of watermelon and maintained the total soluble solids of watermelon. As
the conclusion, fruit rot disease of watermelon caused by F. solani with 15% of lime
extraction may have the possibility to prevent the growth of F. solani and mantained
the post harvest quality of watermelon and merit further research.
