ANTAGONISME BAKTERI Pseudomonad fluorescens TERHADAP JAMUR PATOGEN Fusarium oxysporum f. sp. melonis DI RIZOSFER PERKECAMBAHAN MELON

The aim of research was to prove antagonism bacteria of Pseudomonad fluorescens to inhibiting pathogenic fungal Fusarium oxysporum f. sp. melonis to result in defective. Research activities is undertaken in melon agricultural field in Technical Implementation Unit Agribusiness and Horticulture, Lebo, Sidoarjo; Karang Sinom Village, Indramayu; and Plant Protection Laboratory of Agriculture UPN "Veteran" East Java. This research carried out during October 2013 until February 2014. Method is arranged in a Randomized Completely Design with 3 treatments and 4 replications for antagonistic experiment bacteria of Pseudomonad fluorescens to inhibiting pathogenic Fusarium oxysporum f. sp. melonis, colonization pattern and biological agents in rhizosphere of melon germination using descriptive and destructive methods. In antibiosis experiment bacteria of Pseudomonad fluorescens from rhizosphere of melon germination to pathogenic Fusarium oxysporum f. sp. melonis is used a Randomized Completely Design with 4 treatments and 4 replications. Isolation and screening method of bacteria of Pseudomonad fluorescens have been found 9 isolate and 3 isolate is Pseudomonad fluorescens such as PfN2, PfN5 and PfN7. Antagonistic biological agents experiment to pathogenic fungal showed that PfN7 is the most effective inhibitor with inhibiting percentage 21.88 %, this isolate is used for the next experiment. The result of experiment with colonization pattern and biological agents in rhizosphere of melon germination show that biological agents were effective colonize in rhizosphere of melon germination. Result of statistic analyst showed that antibiosis of antagonist bacteria of Pseudomonad fluorescens from rhizosphere of melon germination have a significant influence for reducing pathogenic fungal Fusarium oxysporum f. sp. melonis with inhibition zone, 2nd days after inoculating has inhibiting percentage 6.25 %, and 4th days after inoculating has significant inhibiting percentage 8.81 %. In 6th days after inoculating has inhibiting percentage 11.88 %, and the most inhibiting percentage is showed in 8th days after inoculating e.g. 18.88 %. Key Words : Fusarium wilt , antagonism, Pseudomonad fluorescens, rhizospher