Judul: Kebugaran Staphylococcus epidermidis BC4, Bacillus subtilis AB89, dan Pseudomonas fluorescens RH4003 dalam Formulasi Biopestisda selama Penyimpanan.
Abstrak: Formulasi biopestisida adalah campuran antara biomassa agens pengendali hayati dengan bahan-bahan yang dapat meningkatkan keefektifan dan kemampuan hidup agens pengendali hayati. Formulasi agens pengendali hayati dapat berupa produk padat atau cair. Ketahanan hidup atau viabilitas bakteri dalam formulasi dipengaruhi oleh banyak faktor diantaranya adalah lama penyimpanan dan bahan pembawa. Penelitian ini bertujuan untuk mengetahui viabilitas Staphylococcus epidermidis BC4, Bacillus subtilis AB89, dan Pseudomonas fluorescens RH4003 dalam formulasi biopestisida selama penyimpanan. B. subtilis AB89, P. fluorescens RH4003 dan bakteri endofit S. epidermidis BC4 diformulasikan dengan dua bahan pembawa yaitu talc powder dan media air yang mengandung xanthan gum. Viabilitas bakteri dihitung menggunakan metode pengenceran berseri dan metode pencawanan (plate count method). Data yang diperoleh kemudian diolah dengan Microsoft Office Excel 2007. Berdasarkan uji viabilitas bakteri di dalam formulasi tepung maupun cair populasinya menurun pada bulan ke-1 setelah penyimpanan, kemudian stabil hingga 5 bulan penyimpanan. Laju pertumbuhan bakteri dalam formulasi selama penyimpanan lebih tinggi pada formulasi cair dibandingkan dengan formulasi tepung. Karakteristik morfologi bakteri sebelum dan setelah penyimpanan tidak ada perubahan.
Keyword: bakteri endofit, formulasi biopestisida, pengendalian hayati, PGPR

Judul: Viabilitas dan Efektivitas Formulasi Bacillus spp. pada Berbagai Bahan Pembawa sebagai Biokontrol Pseudomonas viridiflava
Abstrak: Busuk lunak yang disebabkan antara lain oleh Pectobacterium spp., Dickeya spp., dan Pseudomonas viridiflava merupakan salah satu penyakit yang menjadi kendala dalam budidaya tanaman hortikultura di Indonesia. Mekanisme patogenisitas bakteri-bakteri patogen tersebut dalam menimbulkan gejala busuk lunak terjadi melalui mekanisme quorum sensing. SGT3g, INT1c, NTT3a dan NTT3e adalah Bacillus penghasil enzim AHL-laktonase yang potensial untuk diformulasikan sebagai agen pengendali hayati untuk mengendalikan penyakit busuk lunak di lapangan. Penelitian ini bertujuan menguji talk, gambut dan kaolin sebagai bahan pembawa dalam mempertahankan viabilitas dan efektivitas biokontrol keempat Bacillus spp. tersebut dalam mengendalikan busuk lunak. Observasi viabilitas Bacillus spp. dalam formulasi dilakukan dengan metode Total Plate Count (TPC), sedangkan uji aktivitas penghambatan busuk lunak dilakukan dengan pengujian pada umbi kentang. Hasil uji aktivitas menunjukkan campuran kaolin dan gambut (BP3) dapat mempertahankan 92,7-99,2% populasi Bacillus spp. selama 12 minggu pada suhu ruang (27oC). Keempat formulasi Bacillus spp. memiliki kemampuan yang tinggi dalam menekan virulensi P.viridiflava pada umbi kentang. Kemampuan penghambatan tertinggi ditunjukkan oleh formulasi Bacillus sp. SGT3g pada BP2 dan BP3 serta Bacillus sp. NTT3e pada BP2. Berdasarkan hasil kedua uji tersebut disimpulkan bahwa formulasi Bacillus sp. SGT3g dalam campuran kaolin dan gambut (BP3) paling sesuai digunakan sebagai biokontrol P.viridiflava untuk aplikasi lapang.
Keyword: busuk lunak, bahan pembawa, anti-quorum sensing, P. viridiflava

Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite