The Effect of Legundi (Vitex trifolia) Biofungicide Doses Fermented with Trichoderma on Fusarium Wilt Disease in Several Shallot Varieties (Allium ascalonicum L.)

Fusarium oxysporum f.sp. cepae (FoC), the causing agent of Fusarium wilt disease in shallot, is a destructive pathogen and causes serious crop damage and yield loss. To control this disease, legundi leaf extract biofungicide fermented with T. harzianum was applied. This experiment aimed to determine the effect of Trichoderma fermented legundi biofungicide doses (T. harzianum) on Fusarium wilt disease in two local shallot varieties. The experiment was arranged in a completely randomized factorial design (CRD) with tests in a greenhouse. The dose factor of the Trichoderma fermented legundi biofungicide consisted of 5 levels: 0 ml/plant, 2,5 ml/plant, 5 ml/plant, 7,5 ml/plant, and 10 ml/plant. The shallot variety factor consisted of Keta Monca and Bali Karet. The experimental results showed that the application of legundi Trichoderma biofungicide starting from a dose of 2,5 ml/plant was able to reduce the intensity of Fusarium wilt disease in both shallot varieties, with suppression percentages of 12,17-42,73% (Keta Monca) and 19,56-66,57% (Bali Karet), reduced the infection rate and the area under the disease progress curve (AUDPC). The highest disease suppression is obtained by the application of 10 ml/plant legundi Trichoderma biofungicide. Bali Karet showed lower disease incidence (35,40%) and lower AUDPC (222,7) than Keta Monca (68,74% of disease incidence and 1192,912 AUDPC).