Judul: Population of Plant-hoppers and Spiders in Biointensive and Conventional Rice Croping
Abstrak: Padi merupakan salah satu tanaman serelia penting yang digunakan sebagai makanan pokok sebagian besar penduduk dunia. Padi tergolong dalam tanaman pangan berupa rumput berumpun dan memiliki kemampuan beradaptasi yang tinggi pada berbagai kondisi lingkungan. Penelitian bertujuan mengetahui perbandingan populasi hama wereng dan populasi laba-laba pada pertanaman padi biointensif dan konvensional di Kampung Darim, Kecamatan Terisi, Kabupaten Indramayu, Provinsi Jawa Barat. Metode penelitian yang digunakan adalah metode pengamatan langsung dilakukan dengan menetapkan titik pengamatan secara terpilih yang mewakili bagian tengah lahan sawah dengan ukuran 10 m x 10 m. Pada setiap lahan sawah ditentukan 100 grid pengamatan, grid pengamatan berukuran 1 m2. Data diolah dan dianalisis menggunakan aplikasi Microsoft excel 2013. Hasil penelitian menunjukkan bahwa populasi wereng lebih tinggi pada lahan pertanaman padi dengan perlakuan biointensif, populasi laba-laba lebih tinggi pada lahan pertanaman padi dengan perlakuan biointensif. Spesies yang ditemukan yaitu Araneus inustus, Neoscona theisi, Atypena adelina, Pardosa pseudoannulata, Tetragnathidae sp., Oxyopes javanus, dan Harmochirus sp. Dominasi spesies yang ditemukan yaitu Atypena adelina baik pada lahan dengan perlakuan biointensif maupun konvensional. Famili yang mendominasi pada pada lahan dengan perlakuan biointensif maupun konvensional adalah Famili Araneidae., Rice is one of the important cereal crops which is used as a staple food for most of the world's population. Rice is classified as a food crop in the form of clump grass and has high adaptability to various environmental conditions. This study aims to determine the comparison of planthopper populations and spider populations in biointensive and conventional rice plantations in Darim Village, Terisi District, Indramayu Regency, West Java Province. The research method used is a direct observation method carried out by determining selected observation points that represent the middle of the rice field with a size of 10 m x 10 m. In each rice field, 100 observation grids are determined, the observation grid is 1 m2 in size. The data was processed and analyzed using the Microsoft Excel 2013 application. The results showed that the planthopper population was higher on rice plantations with biointensive treatment, the spider population was higher on rice plantations with biointensive treatment. The species found were Araneus inustus, Neoscona theisi, Atypena adelina, Pardosa pseudoannulata, Tetragnathidae sp., Oxyopes javanus, and Harmochirus sp. The dominant species found was Atypena adelina both on land with biointensive and conventional treatment. The family that dominates on land with biointensive and conventional treatment is the Araneidae family.
Keyword: dominasi, keragaman, musuh alami

Judul: SURVEY OF DISTRIBUTION OF BROWN PLANTHOPPER POPULATION IN RICE CROPS IN SUBANG REGENCY WEST JAVA
Abstrak: Padi (Oryza sativa L.) merupakan komoditas penting sebagai sumber pangan pokok di Indonesia. Budidaya tanaman padi seringkali mengalami kegagalan akibat serangan hama wereng batang cokelat (WBC) Nilaparvata lugens Stål. Penelitian ini bertujuan mengetahui persebaran populasi WBC di Kabupaten Subang, kerapatan populasinya, dan tingkat kerusakan tanaman padi di tiga lokasi ketinggian tempat yang berbeda. Penelitian ini dilakukan dengan menelusuri keberadaan serangan WBC di lahan persawahan di areal kabupaten Subang dan memetakan persebarannya, menentukan lahan perlakuan terinfestasi di tiga lokasi ketinggian tempat berbeda, mengamati tingkat kerusakan tanaman pada umur 4 MST dan kerapatan populasi WBC. Data penunjang diperoleh melalui wawancara terhadap petani tentang teknik budidaya padi setempat kaitannya dengan pengendalian WBC di lahannya. Luas serangan dan intensitas kerusakan tanaman tertinggi 91,5% dan 41%, dengan jumlah populasi WBC tertinggi 1.8 ekor/rumpun ditemukan di lahan padi dataran rendah pada ketinggian 27-38 m dpl, sebaliknya kerusakan paling rendah sebesar 22% dan 4.3% dengan jumlah populasi 0.35 ekor/rumpun ditemukan di dataran tinggi pada 516-526 m dpl. Penggunaan varietas padi Ciherang dan Inpari 31 tidak berpengaruh terhadap jumlah populasi WBC. Lokasi penanaman padi di dataran rendah dengan curah hujan dan suhu lingkungan yang tinggi berkontribusi dalam peningkatan populasi WBC, Rice (Oryza sativa L.) is an important commodity as the staple food in Indonesia. Rice cultivation often fails due to attacks by the brown planthopper (BPH) Nilaparvata lugens Stål. This study aims to determine the distribution of BPH population in Subang Regency, the population density, and the level of damage to rice crops at three different altitude locations. This research was conducted by tracing the presence of BPH infestation in paddy fields in the Subang district area and mapping their distribution, determining the infested treatment areas at three different altitude locations, observing the level of plant damage at 4 WAP and the population density of BPH. Supporting data was obtained through interviews with farmers regarding local rice cultivation techniques in relation to BPH control in their fields. The highest attack area and intensity of crop damage were 91.5% and 41%, with the highest number of BPH populations of 1.8 individuals/hills found in lowland rice fields at an altitude of 27-38 masl, whereas the lowest damage was 22% and 4.3% with the lowest populations of 0.35 individuals/hills found in the highlands at 516-526 masl. Ciherang and Inpari 31 rice varieties had no effect on the number of WBC populations. The location of rice cultivation in the lowlands with high rainfall and ambient temperature contributed to the increase in the BPH population.
Keyword: Intensitas, Ketinggian tempat, Luas serangan, Varietas padi, Altitude, Attack area, Intensity, Rice varieties

Judul: Pembuatan Film Tipis Cu2ZnSnS4 sebagai Lapisan Penyerap Cahaya pada Sel Surya Menggunakan Metode Elektrodeposisi
Abstrak: Thin film of Cu2ZnSnS4 (CZTS) is an alternative semiconductor used as light absorber layer on solar cell. CZTS can replace silicon that commonly used as commercial semiconductor. The advantage of using CZTS as absorber layer is due to the abundance of its chemical composer on earth, and its high value of absorption coefficient. The absorber layer was made by using electrodeposition method on ITO glass substrates. The films were deposited at room temperature using potentiostatic mode with a potential of –1.05 V for 30, 45, and 60 minutes. After that, the films were annealed at two different temperatures, 180 ºC and 500 °C, for 45 minutes in N2/H2S atmosphere. Based on X-ray diffraction analysis, the polycrystalline thin film obtained fall into kesterite crystal phase. This type of crystal was obtained when the CZTS was annealed at 500 °C in H2S/N2 atmosphere. The value of optical band gap energy for the CZTS thin film was 2.2 eV with the film thickness about 1.228–6.366 μm. The sample of CZTS with electrodeposition time of 45 minutes and annealing temperature of 500 °C showed the best result and in conformity with absorber layers criteria for solar cells.
Keyword: semiconductor, ITO glass, CZTS thin film, electrodeposition