Judul: Pengaruh perlakuan benih "BIOPRIMING" dengan Pseudomonas spp terhadap rebah kecambah oleh Pythium sp pada ketimun
Abstrak: Pengendalian benih secara hayati dapat dikombinasikan dengan metode pengendalian yang lain untuk memperoleh hasil yang lebih baik. Biopriming merupakan kombinasi antara perlakuan bakterisasi benih dan perlakuan priming yang masing-masing bertujuan untuk menekan serangan Pythium. Penelitian ini bertujuan untuk mempelajari pengaruh perlakuan benih biopriming dengan menggunakan Pseudomonas spp sebagai agen antagonis untuk mengendalikan penyakit rebah kecambah oleh Pythium sp pada ketimun. Bakteri Pseudomonas spp kelompok fluoresen diisolasi dari rhizosfer kecambah ketimun sehat yang ditanam pada tanah alami dari daerah Cianjur. Isolasi dilakukan pada medium King's B dengan penambahan antibiotik sikloheksimid 100 ppm, ampisilin 50 ppm dan kloramfenikol 12.5 ppm. Pythium diisolasi dengan metode pengumpanan dari tanah daerah Cianjur yang terinfestasi Pythium secara alami. Isolasi Pythium dilakukan pada medium PDA. Patogenisitas semua isolat bakteri diuji dengan uji hipersensitif pada tembakau dan uji pembusukan kentang. Seleksi isolat bakteri secara invitro dilakukan dengan metode biakan ganda. Seleksi isolat bakteri lebih lanjut dilakukan dengan penanaman di rumah kaca untuk memilih lima isolat bakteri yang akan digunakan dalam perlakuan biopriming. Percobaan dilakukan dengan menggunakan rancangan acak lengkap dengan ulangan tiga kali pada masing-masing perlakuan. Data yang diperoleh dianalisa lebih lanjut dengan uji beda nyata terkecil (alpha = 0.05) . ...
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Judul: Pengaruh Pemupukan NPK Terhadap peningkatan Potensi Antagonis Trichoderma Sp. pada Pythium Sp. penyebab Rebah Kecambah Mentimun
Abstrak: Percobaan ini dilakukan untuk mengetahui pengaruh pu- puk N,P,K (dengan kombinasi 15-15-15) terhadap aktivitas Trichoderma sp. sebagai agen antagonis pada Pythium sp. penyebab rebah kecambah mentimun. Percobaan dilakukan di Laboratorium cendawan patogen tumbuhan dan rumah kaca Jurusan Hama dan Penyakit Tumbuhan, Fakultas Pertanian, Institut Pertanian Bogor. Isolat Patogen yaitu Pythium sp. dan antagonis Trichoderma sp. masing-masing diisolasi dari tanah Tajur dan Darmaga kemudian dibiakan pada media PDA. Telah diidentifikasi dua isolat Trichoderma sp. yang diperoleh dari hasil isolasi. Hasil identifikasi sementara menunjukkan bahwa isolat Tri- choderma yang diperoleh adalah T. koningii dan T. harzianum. Kedua isolat tersebut dibiakan secara massal pada medium campuran dedak padi dan serbuk gergaji ( 1 : 1 dalam volume) selama 14 hari. Sedangkan pembiakan massal Pythium sp. dilakukan pada media Corn-Meal Sand selama 7 hari. ...
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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