Mikrobaendofitik Dari Taman Nasionalbatang Gadis Sumatera Utara: Potensinya Dalam Menghasilkan Senyawa Antimikrobaterhadapmikrobapatogen [Endophytic Microbes From Batang Gadis National Park, North Sumatra: Their Potential for Producing Antimicrobes Bioactive Compound Againts Pathogenic Microbes]

Batang Gadis National Park (TNBG) is one of the tropical forests in North Sumatra with megabiodiversity of flora and fauna including microorganism. Endophytic microbes conservation from varieties of forest plants in Batang Gadis National Park has been completed. Nineteen endophytes isolates from TNBG have been screened for their potential on producing bioactive compound against the pathogenic bacteria. Qualitative screening has been done using the growth agar media and identified the clear zone appeared surrounding the bacteria colony. The result indicated that isolate MSCI 87.4 showed high strengthening secresion (4.35) againts Xanthomonas campestris, whereas isolate MSCI 37.1 showed high secretion against Bacillus subtilis (2.69) and Escherichia coli (2.60). Isolate MSCI 37.4 showed potential on producing bioactive compound againts Staphylococcus aureus (4.41). Isolates MSCI 87.4, MSCI37.1, MSCI 37.4 and MSCI 58.1 even could produce bioactive compound against four pathogenic bacteria that are Xanthomonas campestris, Bacilus subtilis, Escherichia coli and Staphylococcus aureus, whereas isolate MSCI 15.5b potential on producing bioactive compound against two isolates namely Xanthomonas campestris and Bacillus subtilis. The endophytes bacteria mainly belong to the Gram negative group and four out of nineteen isolates tested belong to the Gram positive group. The cell mainly coccus and only one is bacilli without fiagella. The five most potential isolates has been maintained under freeze dried condition for futher conservation and study. Thin Layer Analysis using semipolar organic separation solution showed that most isolates identified were able to produce bioactive compound except two isolates i.e. MSCI 48.4a and MSCI 53.1; however further analysis is needed to confirm the product

Peningkatan Galur Pada Bakteri Penghasil Iaa Yang Diisolasi Dari Bintil Akar Tanaman Turi (Strain Improvement on Iaa-producing Bacteria Isolated From Root Nodules of Sesbania Grandiflora (L))

Produksi hormon Indole Acetic Acid (IAA) dari bakteri dapat ditingkatkan melalui peningkatkan kualitas galur. Peningkatan galur dapat dilakukan dengan mutasi kimia dan fisik. Tujuan penelitian ini adalah untuk meningkatkan produksi IAA bakteri yang diisolasi dari bintil akar tanaman turi melalui mutasi asam nitrat dan sinar UV. Bintil berwarna merah muda, sehat dan segar telah diisolasi dari akar tanaman Turi (Sesbania grandiflora (L)). Sebanyak 15 isolat bakteri telah diperoleh dan diuji kemampuannya dalam menghasilkan hormon IAA. Hasil analisis kolorimetri menunjukkan bahwa isolat TC 4.3.1.2 menghasilkan IAA tertinggi (17,72 μg/ml) dalam kultur yang ditambah L-triptofan. Berdasarkan analisis gen 16S rRNA, isolat TC 4.3.1.2 teridentifikasi sebagai Rhizobium sp. BGC8. Isolat penghasil IAA tertinggi diuji dengan perlakuan mutasi. Mutan asam nitrat menghasilkan hormon IAA (20,31-24,48 μg/ml) lebih tinggi dibandingkan mutan UV (0,61-19,55 μg/ml)

Respon Padi Gogo terhadap Pupuk Hayati di Lahan Kering Kabupaten Konawe Selatan, Sulawesi Tenggara

Response of Upland Rice towards Biological Fertilizer on the Dry Land in South Konawe District, South East Sulawesi. As the productivity of upland rice is still low, it requires technology improvement such as high yield variety and biological fertilizer. The purpose of this research was to determine the adaptability of upland rice varieties combined with biological fertilizer application. The experiment was conducted in the dry land of South Konawe District, South East Sulawesi using a factorial randomized block design with four replications of two factors. The first factor was three upland rice varieties namely Inpago LIPI Go1, Inpago LIPI Go2 and local varieties Kolono; the second factor was the combination of inorganic fertilizers and biological fertilizers. The experiment was carried out from December 2013 to March 2014. The results showed that the highest productivity was achieved by Inpago LIPI Go2 (4.5 to 5.2 t/ha) combined with the fertilizer combination as follow; Biofertilizer; Biofertilizer + 25% of recommended inorganic fertilizer; and Biofertilizer + 50% of recommended inorganic fertilizer without loosing the yield