Aplikasi metabolit sekunder dari tiga isolat Pseudomonas fluorescens untuk mengendalikan penyakit antraknosa pada daun kakao

Abstract

Anthracnose caused by Colletotrichum gloeosporoides is an important disease in cocoa. This research aimed to determine the effectiveness of secondary metabolites derived from three isolates of Pseudomonas fluorescens to control cocoa leaves anthracnose, and their influence on the growth of cocoa plants. The research was conducted at a smallholder cocoa plantation in Putat Village, Patuk District, Gunung Kidul Regency, Yogyakarta for four months. A randomized block design was used with four replicates and seven treatments consisted of control, application of secondary metabolites from P. fluorescens P60, P . fluorescens P20, P . fluorescens P8, combination P . fluorescens P60 + P20, P . fluorescens P60 + P8, and P. fluorescens P20 + P8. Variables observed were disease intensity, infection rate, number of healthy shoots and qualitative phenolic compound. Results of the research showed that the secondary metabolites of P. fluorescens P60, P20 and P8 alone or in combination suppressed the disease intensity by 42.01-54.50%. The infection rate caused by metabolite secondary of P. fluorescens P60, P20, P8, P . fluorescens P60+P20, P . fluorescens P60+P8, and P . fluorescens P20+P8 was 0.23; 0.25; 0.26; 0.26; 0.31; and 0.24 units/day, respectively. The secondary metabolites of P . fluorescens P60 increased the number of healthy shoots by 67.44 %. The secondary metabolites of P. fluorescens P60 increased phenolic compounds (tannin, saponin, and glycosides) in cocoa leaves.

Keywords

• leaves anthracnose
• colletotrichum gloeosporoides
• cocoa
• secondary metabolites
• pseudomonas fluorescen