| Abstract | Anthracnose caused byÃÂ Colletotrichum gloeosporoidesÃÂ is an important disease in cocoa.ÃÂ This research aimed toÃÂ determineÃÂ the effectiveness of secondary metabolites derived from three isolatesÃÂ ofÃÂ Pseudomonas fluorescensÃÂ to controlÃÂ cocoaÃÂ leaves anthracnose, and their influence on the growth of cocoa plants. The research was conducted atÃÂ a smallholderÃÂ cocoaÃÂ plantationÃÂ inÃÂ Putat Village, Patuk District, Gunung Kidul Regency, YogyakartaÃÂ for four months.ÃÂ A randomized block design was used with four replicates and seven treatments consisted of control, application of secondary metabolitesÃÂ fromÃÂ P. fluorescensÃÂ P60,ÃÂ P. fluorescensÃÂ P20,ÃÂ P. fluorescensÃÂ P8, combinationÃÂ P. fluorescensÃÂ P60 + P20,ÃÂ P. fluorescensÃÂ P60 + P8,ÃÂ andÃÂ P. fluorescensÃÂ P20 + P8. VariablesÃÂ observed were disease intensity, infection rate, number of healthy shoots andÃÂ qualitativeÃÂ phenolic compound. Resultsof the research showed that the secondary metabolitesÃÂ ofÃÂ P. fluorescensÃÂ P60, P20 and P8 alone or in combinationÃÂ ÃÂ suppressedÃÂ the disease intensityÃÂ by42.01-54.50%. The infection rate causedÃÂ by metabolite secondary ofÃÂ P. fluorescensÃÂ P60, P20, P8,ÃÂ P. fluorescensÃÂ P60+P20,ÃÂ P. fluorescensÃÂ P60+P8,andÃÂ P. fluorescensÃÂ P20+P8ÃÂ wasÃÂ 0.23; 0.25; 0.26; 0.26; 0.31; and 0.24 units/day,ÃÂ respectively. The secondary metabolitesÃÂ ofÃÂ P. fluorescensÃÂ P60 increasedÃÂ the number of healthy shootsÃÂ byÃÂ 67.44 %. The secondary metabolitesÃÂ ofÃÂ P. fluorescensÃÂ P60 increasedÃÂ phenolic compoundsÃÂ (tannin, saponin, and glycosides) in cocoa leaves.[Keyword:ÃÂ leaves anthracnose,ÃÂ Colletotrichum gloeosporoides,ÃÂ cocoa,ÃÂ secondary metabolites,ÃÂ Pseudomonas fluorescens]ÃÂ AbstrakAntraknosaÃÂ yang disebabkan olehÃÂ Colletotrichum gloeosporioidesÃÂ merupakan penyakit penting pada tanaman kakao.ÃÂ Penelitian bertujuan mengkaji keefektifan metabolit sekunderÃÂ dariÃÂ tiga isolatÃÂ Pseudomonas fluorescensÃÂ untuk mengendalikanÃÂ penyakit antraknosaÃÂ padaÃÂ daun kakao, serta pengaruhnya terhadap pertumbuhan tanaman kakao. Penelitian dilaksanakan di perkebunan kakao rakyat, Desa Putat, Kecamatan Patuk, Kabupaten Gunung Kidul, YogyakartaÃÂ selama empat bulan. Penelitian menggunakan rancangan acak kelompokÃÂ untuk menguji 7 perlakuan yang diulang 4 kali, perlakuan yang diuji adalahÃÂ kontrol, aplikasi metabolit sekunderÃÂ P. fluorescens P60, P. fluorescens P20, P. fluorescens P8, kombinasi P. fluorescens P60+P20, P. fluorescens P60+P8,ÃÂ dan P. fluorescens P20+P8. VariabelÃÂ pengamatanÃÂ meliputi intensitas penyakit, laju infeksi, jumlah tunas sehat, dan kandungan senyawa fenolÃÂ secara kualitatif. Hasil penelitian menunjukkan bahwa perlakuanÃÂ metabolit sekunderÃÂ P. fluorescensÃÂ P60, P20, dan P8 secara tunggal dan gabungan mampu menekan intensitas penyakit berkisar 42,01-54,50%. Laju infeksi perlakuan metabolit sekunderÃÂ P. fluorescens P60,ÃÂ P. fluorescens P20, P. fluorescens P8, kombinasi P. fluorescens P60+P20, P. fluorescens P60+P8 dan P. fluorescens P20+P8 berturut-turutÃÂ 0,23; 0,25; 0,26; 0,26; 0,31; dan 0,24 unit/hari. Metabolit sekunderÃÂ P. fluorescens P60 meningkatkan jumlah tunas sehat sebesarÃÂ 67,44%. PerlakuanÃÂ P. fluorescens P60 meningkatkan senyawa fenol (saponin, tanin, dan glikosida) pada daun kakao.[KataÃÂ kunci: antraknosa daun,ÃÂ Colletotrichum gloeosporoides,ÃÂ kakao, metabolitÃÂ sekunder,ÃÂ Pseudomonas fluorescens] |
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