EFFECT OF ARBUSCULAR MYCORRHIZAL FUNGI BIOFERTILIZER ON THE GROWTH OF CASHEW SEEDLING

The effects of several arbuscular mycorrhizal fungi (AMF) on thegrowth, nutrient uptake (nitrogen, phosphorus, and potassium), and acidphosphate activity of two promising numbers of Anacardium occidentaleseedling were evaluated. The experiment was conducted in the greenhouse of Indonesian Spices and Medicinal Crops Research Institute(BALITTRO) in 2002 for six months on a randomized design with twofactors and four replicates. First factor was isolate (six isolates of AMFand one control) consisting of : 1) control; 2) Glomus aggregatum; 3)Glomus etunicatum; 4) Mycofer; 5) Glomus sp.; 6) a mixture of Glomussp1, Glomus sp2, Glomus sp3, Glomus sp4, Glomus etunicatum,Gigaspora margarita, Gigaspora sp., and Enthropospora sp., and 7)Gigaspora sp. The second factor was two cashew promising numbers :Asembagus and Wonogiri. The results showed that AMF inoculationsignificantly affected the growth of cashew. Mycofer and mixed AMFwere more effective to Wonogiri promising number, while for Asembaguspromising number inoculation of mycofer was more effective. Inoculationwith mycofer to Asembagus promising number increased the uptake of Pand K nutrients by 65 and 53% while inoculation with mycofer and mixedAMF to Wonogiri promising number increased the uptake of N, P and Knutrients by 55, 38, and 17%, and by 18, 31, and 17%. Moreover, theAMF inoculation resulted in higher phosphatase activity. In mycorrhizalAsembagus promising number infected by mixed AMF, the increment ofphosphatase activity was 136.5%, whether in Wonogiri promising numberinfected by mycofer, the increment of phosphatase activity was 80% thancontrol. Key words: Anacardium occidentale, promising number, growth,phosphatase activity ABSTRAK Pengaruh Pupuk Hayati Fungi Mikoriza Arbuskula(FMA) terhadap Pertumbuhan Benih Jambu Mete Penelitian ini bertujuan untuk mengetahui pengaruh beberapa jenisfungi mikoriza arbuskula (FMA) terhadap pertumbuhan, serapan hara danaktivitas enzim fosfatase dari dua nomor harapan benih jambu mete(Anacardium occidentale). Penelitian dilakukan di rumah kaca Balittropada tahun 2002 selama 6 bulan, menggunakan rancangan acak yangterdiri dari dua faktor dan diulang empat kali. Faktor pertama adalahisolate (6 jenis isolat FMA dan satu kontrol) yaitu: 1). kontrol; 2). Glomusaggregatum; 3) Glomus etunicatum; 4). Mycofer; 5). Glomus sp.; 6).campuran dari Glomus sp1, Glomus sp2, Glomus sp3, Glomus sp4, Glomusetunicatum, Gigaspora margarita, Gigaspora sp., Enthropospora sp., dan7). Gigaspora sp. Faktor kedua adalah nomor harapan jambu mete, yaituAsembagus dan Wonogiri. Hasil penelitian mendapatkan bahwa inokulasiFMA berpengaruh nyata terhadap pertumbuhan jambu mete. Mycofer dancampuran FMA lebih efektif berpengaruh terhadap nomor harapanWonogiri, sedangkan mycofer lebih efektif berpengaruh terhadap nomorharapan Asembagus. Serapan hara P dan K pada nomor harapanAsembagus yang diinokulasi mycofer meningkat sebesar 65 dan 53%,sedangkan nomor harapan Wonogiri yang diinokulasi mycofer dancampuran FMA, serapan hara N, P, dan K meningkat masing-masingsebesar 55; 38; dan 17%, dan 18; 31; dan 17%. Selain itu, inokulasi FMAdapat meningkatkan aktivitas fosfatase akar jambu mete. Peningkatanaktivitas fosfatase akar jambu mete nomor harapan Asembagus yangterinfeksi oleh campuran FMA sebesar 136,5%, sedangkan pada nomorharapan Wonogiri yang terinfeksi mycofer, peningkatnnya sebesar 80%dibandingkan kontrol. Kata kunci: Anacardium occidentale, nomor harapan, pertumbuhan,aktivitas fosfatase