Biomass Production and Formulation of Bacillus Subtilis for Biological Control

Bacillus subtilis is a widespread bacterium found in soil, water, and air. It controls the growth of certain harmful bacteria and fungi, presumably by competing for nutrients, growth sites on plants, and by directly colonizing and attaching to fungal pathogens. When applied to seeds, it colonizes the developing root system of the plants and continues to live on the root system and provides protection throughout the growing season. The study on biomass production and formulation of B. subtilis for biological control was conducted in the laboratory of Department of Plant Pathology, College of Agriculture, University of the Philippines Los Baños (UPLB-CA), College, Laguna from May to July 2005. The objective of the study was to determine the optimum pH and a good carbon source for biomass production of B. subtilis and to develop a seed treatment formulation of B. subtilis as biological control agent. Results showed that the optimum pH for growth of B. subtilis was pH 6 (1.85 x 109 cfu/ml). In laboratory tests for biomass production using cassava flour, corn flour, rice flour, and brown sugar as carbon sources, it grew best in brown sugar plus yeast extract medium (6.8 x 108 cfu ml-1 in sterile distilled water and 7.8 x 108 cfu ml-1 in coconut water). In test for bacterial biomass carriers, talc proved to be the best in terms of number of bacteria recovered from the seeds (3.98 x 105 cfu seed-1)

Biologi, Gejala Serangan, Dan Pengendalian Hama Bubuk Jagung Sitophilus Zeamais Motschulsky (Coleoptera: Curculionidae)

Salah satu kendala dalam penyimpanan jagung adalah serangan hamagudang. Salah satu hama gudang jagung adalah Sitophilus zeamaisMotschulsky (Coleoptera: Curculionidae). Hama ini ditemukan didaerah panas maupun lembap. Hama ini bersifat polifag, dapatmerusak serealia seperti beras/gabah, jagung, gandum, dan sorgum,namun dilaporkan sebagai hama penting pada jagung. Kehilanganhasil jagung di wilayah tropis akibat S. zeamais berkisar antara 30-100%. Biji jagung yang disimpan selama 6 bulan menunjukkankerusakan 85% dan bobot biji menyusut 17%. Telur hama tersebutdiletakkan di dalam biji dan dalam beberapa hari akan menetasmenjadi larva. Larva menyelesaikan siklus hidupnya di dalam biji.Telur berwarna putih Bening, berbentuk lonjong, lunak dan licin,berukuran 0,7 mm x 0,3 mm. Larva berwarna putih kekuningan,tidak bertungkai, kepala berwarna cokelat, terdiri atas empat instar,panjang 1,5–4 mm. Periode larva berlangsung 25 hari. Imago S.zeamais berukuran 3-4,5 mm. Hama S. zeamais dapat dikendalikandengan cara: 1) menyimpan jagung dalam wadah maupun gudangsecara higienis, 2) menanam varietas tahan, 3) menggunakanmusuh alami yaitu parasit, predator, dan patogen, seperti parasitoidLariophagus distinguendus dan Anisopteromalus calandrae, sertapatogen Beauveria bassiana, 4) memanfaatkan insektisida nabatiyang memiliki toksisitas tinggi terhadap S. zeamais, yaitu Ageratumconnyzoides (bandotan), Andropogon nardus (serai), Allium sativum(bawang merah), Nicotiana tabacum (tembakau), Zingiber officinale(jahe), dan Azadirachta indica (mimba), serta 5) menyemprotkaninsektisida sintetis metil pirimifos

Efektivitas Biopestisida Bacillus Subtilis Bnt 8 Dan Pestisida Nabati Untuk Pengendalian Penyakit Hawar Pelepah Dan Upih Daun Jagung

Effectiveness of the biopesticide of Bacillus subtilis BNt 8 and botanical pesticide in controlling banded leaf and sheath blight disease on maize. Banded leaf and sheath blight disease (BLSB) caused by the fungus Rhizoctonia solani is difficult to control because it pertained soil borne fungus that can survive in a long time in the soil. Control the disease with synthetic pesticide causing contamination to the environment, so that an environmentally friendly alternative control is needed. This study aimed to obtain a Bacillus subtilis formulation as biological agents and selected botanical pesticides that effective to control BLSB in the field. The study was conducted at the Plant Pathology Laboratory of Indonesia Cereals Research Institutein Maros and at the Bajeng Experimental Farm in Gowa, held from February to August 2015. The reatments consists of several botanical pesticides, B. subtilis formulation, a synthetic fungicide, positive and negative controls. In vitro test was inhibition test between botanical pesticide with R. solani and antagonistic test between the B. subtilis and botanical pesticides, each of them consists of 6 treatments and 3 replications, while the field activity consists of test of effectiveness of single treatment and combination between B. subtilis formulation and botanical pesticides. The results showed that combination of formulated B. subtilis with botanical pesticide of cloves leaves, betel leaves, and turmeric were not significantly different from single treatment of formulated B. subtilis and botanical pesticides. Formulated B. subtilis suppressed the severity of BLSB as much as 39.1% and yield reached 8.4 t/ha

Evaluasi Lima Jenis Inner Carrier Dan Formulasi Bacillus Subtilis Untuk Pengendalian Hawar Pelepah Jagung (Rhizoctonia Solani Kuhn)

Evaluation of five inner carriers and Bacillus subtilis formulation to control banded leaf and sheath blight (Rhizoctonia solani Kuhn). One alternative control method against plant pathogens is the use of antagonistic microorganisms, such as Bacillus subtilis. The use of the antagonistic bacteria on corn especially in Indonesia is still lack. The objective of this research was to evaluate some inner carrier and to make formulated antagonistic B. subtilis to be used as biological control agents on corn diseases. This research consists of laboratory and greenhouse activities. The laboratory activities consist of B. subtilis biomass production, formulation of B. subtilis, and evaluation of five types of inner carrier. In the greenhouse, testing the formulation B. subtilis with talc as an inner carrier, which is compared with the treatment solution of B. subtilis, nordox, metalaxyl fungicides. The data collected in this study were percentage of germination, damping off due to pathogen R. solani, plant height, plant fresh weight, and percentages of R. solani incidence on 14 DAP. The results showed that talc powder and corn flour were the best inner carrier to be used in sorage formulation of antagonistic Bacillus. Formulated Bacillus subtilis TM4 showed no negative affect on seed germination and able to suppress the development of R. solani in greenhouse

Skrining Ketahanan Galur S1 Jagung Terhadap Penyakit Bulai Dan Pembentukan Galur S2 Tahan Penyakit Bulai

Biotic stress, especially downy mildew (Peronosclerospora philippinensis) incidence, is one of the most important constraints in the development of corn in the country, because it attack on young plant of susceptible varieties, it can cause damage up to 100%. Resistance screening of 84 of S1 maize lines to downy mildew and the formation of S2 lines resistant to downy mildew was conducted in Bajeng Experimental Farm at Gowa, South Sulawesi lasted from February to May 2013. This study aimed to screen the S1 lines resistant to downy mildew and forming S2 lines resistant to downy mildew. Four weeks before the S1 lines planted, the source of inoculum (Anoman variety) was planted in two rows around the test plot. One week after Anoman was planted, it was sprayed with a conidial suspension of the fungus P. philipinensis in the early morning. Three weeks after inoculation of Anoman, 84 of S1 lines to be screened for downy mildew were planted. In this test, resistant check MR14 and susceptible check Anoman was included, each planted in two rows along the 5 m, a spacing of 75 x 25 cm with two replications. Urea fertilizer was used at a dose of 350 kg/ha and Ponska with a dose of 300 kg/ha. Observation of the percentage of downy mildew incidence started at 30 days after planting. The results showed that only three lines and MR14 resistant showed moderately resistant to downy mildew. Percentage of disease incidence ranged from 36–100 percent. However, from this test a number of 580 S2 lines resistant to downy mildew were obtained

Genetic Diversity of S3 Maize Genotypes Resistant to Downy Mildew Based on Ssr Markers

The compulsory requirement for releasing new high yielding maize varieties is resistance to downy mildew. The study aimed to determine the level of homozygosity, genetic diversity, and genetic distance of 30 S3 genotypes of maize. Number of primers to be used were 30 polymorphic SSR loci which are distributed over the entire maize genomes. The S3 genotypes used were resistant to downy mildew with homozygosity level of >80%, genetic distance between the test and tester strains >0.7, and anthesis silking interval (ASI) between inbred lines and tester lines was maximum 3 days. The results showed that 30 SSR primers used were spread evenly across the maize genomes which were manifested in the representation of SSR loci on each chromosome of a total of 10 chromosomes. The levels of polymorphism ranged from 0.13 to 0.78, an average of 0.51, and the number of alleles ranged from 2 to 8 alleles per SSR locus, an average of 4 alleles per SSR locus. The size of nucleotides in each locus also varied from 70 to 553 bp. Cophenetic correlation value (r) at 0.67 indicated that the Unweighted Pair-Group Method Using Arithmetic Averages (UPGMA) was less reliable for differentiating genotypes in five groups. Of the total of 30 genotypes analyzed, 17 genotypes had homozygosity level of >80% so it can be included in the hybrid assembly program

Identifikasi Molekuler Menggunakan Gen 16S-rNA Dan Seleksi Limbah Organik Sebagai Carrier Terhadap Rhizobakteri Indigenous Asal Rhizosfer Padi Sawah

Penelitian terdahulu telah berhasil membuktikan secara in-vitro rhizobakteri indigenous yang diisolasi dari rhizosfer padi sawah, yaitu isolat kode KMV 5 dan GMP 2 berpotensi sebagai agen bioremediasi, biofertilizer dan memiliki aktivitas antimikroba tertinggi. Namun identitas strain isolat tersebut belum diketahui dan carrier yang tepat untuk menunjang pemanfaatannya sebagai agen hayati belum ditemukan.  Penelitian ini bertujuan untuk (1) melakukan identifikasi molekuler terhadap isolat rhizobakteri indigenous KMV5 dan GMP2 untuk mengetahui strain dengan metode sekuensing gen 16S-rNA  melalui tahapan ekstraksi DNA, amplifikasi gen 16S-rRNA dan PCR. (2) melakukan seleksi terhadap limbah organik yaitu air cucian beras, air kelapa dan molase sebagai carrier yang tepat bagi kedua rhizobakteri dengan metode pengamatan nilai absorbansi pada spektrofotometer UV-VIS dengan panjang gelombang 550 nm. Hasil penelitian diperoleh (1) rhizobakteri indigenous isolat KMV5 dan GMP2 teridentifikasi memiliki tingkat homologi 93%-95% dengan Bacillus cereus strain ATCC 14579 (2) media organik terbaik dan tepat sebagai carrier  adalah air cucian beras

Identifikasi Molekuler Menggunakan Gen 16S-rNA Dan Seleksi Limbah Organik Sebagai Carrier Terhadap Rhizobakteri Indigenous Asal Rhizosfer Padi Sawah

Penelitian terdahulu telah berhasil membuktikan secara in-vitro rhizobakteri indigenous yang diisolasi dari rhizosfer padi sawah, yaitu isolat kode KMV 5 dan GMP 2 berpotensi sebagai agen bioremediasi, biofertilizer dan memiliki aktivitas antimikroba tertinggi. Namun identitas strain isolat tersebut belum diketahui dan carrier yang tepat untuk menunjang pemanfaatannya sebagai agen hayati belum ditemukan.  Penelitian ini bertujuan untuk (1) melakukan identifikasi molekuler terhadap isolat rhizobakteri indigenous KMV5 dan GMP2 untuk mengetahui strain dengan metode sekuensing gen 16S-rNA  melalui tahapan ekstraksi DNA, amplifikasi gen 16S-rRNA dan PCR. (2) melakukan seleksi terhadap limbah organik yaitu air cucian beras, air kelapa dan molase sebagai carrier yang tepat bagi kedua rhizobakteri dengan metode pengamatan nilai absorbansi pada spektrofotometer UV-VIS dengan panjang gelombang 550 nm. Hasil penelitian diperoleh (1) rhizobakteri indigenous isolat KMV5 dan GMP2 teridentifikasi memiliki tingkat homologi 93%-95% dengan Bacillus cereus strain ATCC 14579 (2) media organik terbaik dan tepat sebagai carrier  adalah air cucian beras