Efficacy of Some Systemic Fungicides for the Control of Phytophtora parasitica in Stem Rot of Betel Vine

Abstract

The efficacy of five systemic fungicides was compared in-vitro for the control of Phytophthora parasitica Dqst., the causal organism of stem rot of betel vine in Khonkaen Province, Thailand. The radial growth of fungal colonies was assessed on potato dextrose agar (PDA) impregnated with the different fungicides. The growth of the fungal hyphae from the fungal disk was completely inhibited when the PDA was impregnated with either ofurace (Vamine 15% WP), or benalaxyl (Galben 10% WP) at concentrations of 50, 100, 250 and 500 ppm a.i., etridiazole (Terrazole 35%Wp) at 100, 250 and 500 ppm a.i. and metalqxyl (Ridomil 35% WP) at 500 ppm a.i. fosetyl aluminium (Aliette 80% WP) was unable to completely inhibit the growth of the fungal hyphae even at a concentration of 500 ppm a.i.