Judul: Respon kedelai clark 63 normal dan clark rj1 terhadap pemupukan nitrogen
Abstrak: Penelitian ini bertujuan untuk mengetahui kontribusi N bakteri Rhizobium japonicum, dengan mengetahui jumlah N-fiksasi dalam bahan kering dan biji, nilai ekuiva­len N-pupuk terhadap N-fiksasi, beberapa sifat pertumbuhan dan produksi. Yang diperqunakan adalah galur-galur hampir isogenik Clark 63 (berbintil akar) dan Clark rj1 (tidak berbintil akar). Dipakai Rancanqa n Kelompok Terpisah dengan empat V ulangan. Galur kedelai di tempatkan sebagai perlakuan baris dan pemupulcan nitrogen sebagai perlakuan lajur. Taraf pupuk nitrogen adalah: o, 45, 90 dan 135 kg N/ha dalam bentuk urea. Pola respon basil biji Clark 63 terhadap pemupukan nitrogen bersifat kuadratik dengan maksimum pada 90 kg N/ ha, sedangkan pada Clark rj1 naik secara linier sampai 135 kg N/ha dan saling berpotongan pada 121 kg N/ha. Penamt,ahan pup uk nitrogen menaikkan jumlah N-bahan kering dan biji, tetapi menurunkan jumlah N-fiksasi pada Clark 63, Kontribusi N-fiksasi pada bahan kering dan biji masing-masing 46 % ctan 56 % dengan rata-rata 51 %, yang ekuivalen dengan N-pupuk 91 kg/ha. Pada pemupukan antara 50 dan 121 kg N/ha, N-fiksasi dan N-pupuk menghasilkan biji yang optimum, Disim2ulkan juga bahwa di atas 121 kg N/ha bintil akar bersifat para­sitis dan menurunkan produksi Clark 63.
Keyword: Kontribusi N bakteri, Rhizobium japonicum, Galur kedelai, Pemupukan nitrogen, Clark 63, Bintil Akar

Judul: Pengaruh pemupukan N, P dan K terhadap perkembangan bintil akar, pertumbuhan dan produksi kedelai clark 63
Abstrak: Penelitian ini bertujuan untuk mempelajari pengaruh pemberian pupuk N, P dan K terhadap perkembangan bintil akar, pertumbuhan dan produksi kedelai Clark 63 normal. Digunakan Rancangan Anak-anak Petak Terbagi dengan tiga ulangan. Dua taraf pupuk- N (Urea), yaitu: 0 dan 100 kg N/ha merupakan petak utama; empat taraf pupuk P (TSP), yaitu: 0, 100, 200 dan 300 kg P2o5/ha merupakan anak petak dan dua taraf pupuk K (ZK), yaitu: 0 dan 100 kg K20/ha merupakan anak-anak- petak. Pengamatan dilakukan untuk tinggi tanaman, jumlah dan bobot bintil akar, komponen produksi dan produksi bij i kering/ha, jumlah N bah an kering tanaman dan jumlah N biji kedelai. Pemupukan 100 kg N/ha tidak menaikkan tinggi tanaman secara nyata, Pemupukan 300 kg P205/ha memberikan tinggi tanaman yang tertinggi yang berbeda nyata dengan taraf pemupukan 0 kg P205/ha. Pemupukan 100 kg K20/ha tidak memperlihatkan menaiknya tinggi tanaman secara nyata. Pemupukan 100 kg N/ha menurunkan jumlah dan bobot bintil akar. Pemupukan 200 kg P205/ha memberikan jumlah dan bobot bintil akar yang tertinggi. Pemupukan K20/ha mempengaruhi jumlah dan bobot bintil.
Keyword: Glycine max;, Fertilizer;, Soybean production;, Bogor Agricultural University;

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