Judul: The potency of antifungal bioactive compound producing bacteria to control rice sheath blight disease
Abstrak: The objectives of this research were to (i) screen some potential bacteria as biological control agents of the sheath blight disease caused by R. solani, (ii) identify character of the selected bacteria strains as biological control agents, and (iii) characterize the antifungal activities of the antifungal bioactive compound produced by the selected strains against R. solani. The antagonist bacteria were isolated from rhizospheric soil, rice plant, and pond water collected from several locations. Screening of bacteria strains on the growth inhibition of R. solani was conducted in the laboratory, while the selection of bacteria for their effectiveness to suppress sheath blight disease were done in the screen house. The result of this research showed that there are three bacterial isolates which antifungal activity significantly suppressed the rice sheath blight disease, i.e. TT47, SS19, and BR2 with suppression ability of 79,6, 56,4, and 49,47%, respectively. Molecular analysis of partial sequence of 16S rRNA showed that SS19, TT47, and BR2 isolates were Serratia marcescens, Ralstonia pickettii, and Bacillus subtilis, respectively. These biocontrol agents are not phythotoxic, produce siderophore, and phosphate-solubilizing. S. marcescens SS19 and R. pickettii TT47 were chitin-degrading bacteria but B. subtilis BR2 was not. The filtrate from fermentation broth of the R. pickettii TT47 and B. subtilis BR2 inhibited the growth of R. solani. The antifungal bioactive compound was relatively stable on pH range from acidic to basic (pH 4, pH 7, and pH 10). The optimum activity of antifungal bioactive compound was at room temperature (25-27 0C) and tend to decrease at higher temperature (60, 80. 100, and 121 0 Key words: The rice sheath blight, antifungal bioactive compounds, Serratia marcescens, Ralstonia pickettii, Bacillus subtilis. C). The antifungal activity of hexane extract of R. pickettii TT47 and ethyl acetate extract of B. subtilis BR2 in vitro revealed significant growth inhibition to R. solani, respectively by 86,3% and 77,8%. MIC of hexane extract and ethyl acetate extract were 0,1 mg/l and 10 mg/l respectively, and both extracts are not phythotoxic against the rice seedling.
Keyword: Bacillus subtilis, Rhizoctonia solani Kühn, Plant diseases

Judul: Pengaruh Suhu, pH, dan Konsentrasi terhadap Senyawa Bioaktif Antifungi Ralstonia pickettii dalam Menekan Pertumbuhan Rhizoctonia solani
Abstrak: Rice sheath blight disease, caused by Rhizoctonia solani is an important disease on rice and loss of harvest up to 30%. Ralstonia pickettii was one of the biological agent from the group of bacteria which was able to suppress the growth of R. solani. In the laboratory scale, a filtrate of R. pickettii antifungal bioactive compound was able to suppress the growth of fungi up to 100%. Temperature and pH were the factors which were expected to influence the bioactive compound activity. The concentration of this antifungal bioactive filtrate also influenced the growth of R. solani inhibition. Therefore, this research was aimed to know the effectiveness of temperature, pH and concentration of R. pickettii to suppress the growth of R. solani. This research used factorial randomize complete design (RAL) which temperature: 25oC, 30oC and 40oC as the first factor and pH: 5, 6, 7, 8, and 9, were the second factor in three times of repetition. The result of this research showed that at temperature of 25oC and 35oC, antifungal bioactive compound were effective to suppress R. solani activity and pH did not show significant effect to bioactive compound activity. The concentration of 7.5 and 10 % was able to suppress R solani with 40% of the inhibition value.
Keyword: 

Judul: Studi kasus migran pedagang kaki lima di pasar Senen, Jakarta Pusat
Abstrak: Sejak Jakarta menjadi ibukota negara RI, Jakarta tidak pernah sepi dari arus migrasi penduduk. Masuknya para migran ke Jakarta disebabkan karena pertumbuhan fisik yang nyata, yaitu dari pembangunan gedung perkantoran, fasilitas hiburan dan lainnya, memberi daya tarik bagi orang bukan penduduk Jakarta. Termasuk di antara migran adalah kaum golongan kecil yang berasal dari kalangan sirkuit bawah desa. Alasan utama migrasi di sirkuit bawah, yaitu khususnya yang akhirnya bekerja sebagai pedagang kaki lima di Pasar Senen ini pindah ke Jakarta, adalahJakarta menawarkan kesempatan kerja bagi siapa saja yang mau bekerja. Karena di desa tak ada pekerjaan yang dapat menampung golongan muda, kaum migran meninggalkan desa menuju Jakarta. Pola migrasi masuk ke Jakarta tidak dipengaruhi oleh kemungkinan golongan muda mampir di kota-kota kecil sebelum tiba di Jakarta. Keberanian dan tekad bulat meninggalkan desa asal didorong pula oleh sumber cerita tentang Jakarta (saudara/kenalan) yang juga mengalami bahwa setiba di Jakarta mereka akan langsung bekerja. Pendidikan rendah, tidak memiliki ketrampilan, orang petani/buruh tani, merupakan bagian kecil latar tua belakang sosial migran pedagang kaki lima. Memperoleh pekerjaan apa saja asal halal pada mulanya, tempat tinggal dimana saja, modal kecil dan pendapatan harian yang rendah juga mewarnai hidup para migran pedagang kaki lima di Jakarta. Namun sekalipun demikian mereka tetap hidup, bahkan dapat mengirim uang ke desa asal, pulang ke desa minimum setahun sekali dan sedikit-sedikit mampumenabung. Bekerja sebagai pedagang kaki lima sudah ditekuni selama lebih dari lima tahun bahkan ada yang lebih dari tujuh tahun. Inipun dimulai setelah minimum selama dua tahun migran mengerjakan apa saja di Pasar Senen: yang penting dapat uang dan bisa hidup di Jakarta. Bahkan modal membuka usaha kaki lima diperoleh dari selama bekerja mula-mula itu. untuk pengumpulan upah Sekalipun terdapat kenaikan tingkat kehidupan sosial di kota dibandingkan dari desa, kaum migran pedagang lima di Pasar Senen ini tetap berada bawah kota. di kaki bawah sirkuit Ikatan-ikatan baru di kota hampir tidak terjadi kecuali ikatan-ikatan kedaerahan yang terus dipertahankan.
Keyword: