Judul: PRELIMINARY YIELD TRIAL of 35 RICE LINES (Oryza sativa L.) of F5 and F6 GENERATIONS as SHORT GENOTYPE for MULTICANOPY LINES
Abstrak: Sistem budidaya multikanopi merupakan teknik menanam padi yang mengombinasikan genotipe pendek dengan genotipe tinggi untuk ditanam secara berdekatan dalam satu lubang tanam. Penelitian ini bertujuan mengevaluasi daya hasil dan keragaan galur padi sebagai genotipe pendek pada sistem multikanopi. Tiga puluh lima galur padi generasi F5 dan F6 dan dua varietas pembanding digunakan sebagai genotipe pendek, dengan galur IPB187-F-40-1-1 sebagai genotipe tinggi. Penelitian ini dilaksanakan sejak Februari hingga Juli 2023 di Kebun Percobaan Sawah Baru, Bogor. Rancangan kelompok lengkap teracak (RKLT) dengan tiga ulangan digunakan dalam percobaan ini. Faktor genotipe berpengaruh sangat nyata terhadap seluruh karakter genotipe pendek. Terdapat delapan galur dengan produktivitas lebih tinggi daripada kedua pembanding di lingkungan multikanopi. Pola tanam multikanopi mampu meningkatkan rata-rata produktivitas total varietas pembanding sebesar 22,28% dibandingkan monokultur. Karakter tinggi tanaman vegetatif (TTV), jumlah anakan produktif (JAP), jumlah gabah bernas per malai (JGBM), dan bobot seribu butir (BSB) digunakan sebagai kriteria seleksi karena memiliki nilai pengaruh langsung yang besar terhadap produktivitas genotipe pendek. Karakter JAP dan JGBM diberi bobot lebih besar karena memiliki keragaman genetik yang lebih luas. Seleksi berdasarkan indeks seleksi terboboti dengan intensitas sebesar 20% menghasilkan delapan galur terbaik sebagai galur potensial. Galur potensial tersebut mencakup galur IPB201-F-15, IPB201-F-13, IPB204-E-11, IPB200-F-42, IPB200-F-30, IPB201-F-10, IPB200-F- 40, dan galur IPB200-F-32., The multi-canopy cropping system is a rice cultivation technique that combines short genotype with tall genotype to be planted closely on the same hill. This study aimed to evaluate the yield and agronomic performance of rice lines as a short genotype for the multi-canopy system. Thirty-five rice lines of F5 and F6 generation and two check varieties were used as short genotype, with IPB187-F-40- 1-1 as tall genotype. The experiment was conducted from February to July 2023 at the Sawah Baru experimental station at Babakan, Bogor; and was arranged in a randomized completed block design (RCBD) with three replications. The genotype's effect was highly significant for all traits related to the short genotype. In the multi-canopy system, eight lines exhibited higher productivity than both checks. The check varieties in the multi-canopy system achieved an average total yield of 22.28% higher than that of the monoculture. The vegetative plant height (VPH), number of productive tillers (NPT), number of filled grains per panicle (NFG), and thousand-grain weight (TGW) traits were employed as target selection because of their significant direct effects on the productivity of short genotypes. NPT and NFG were assigned higher weights because of their broader genetic diversity. Selection based on a weighted standardised selection index with an intensity of 20% yielded eight best-performing lines as promising lines. These promising lines included IPB201-F-15, IPB201-F-13, IPB204-E-11, IPB200-F-42, IPB200-F-30, IPB201-F-10, IPB200-F-40, and IPB200-F-32.
Keyword: cropping system, genetic parameter, path analysis, selection indices, yield advantage

Judul: Preliminary Yield Trial of 84 Lowland Rice Lines (Oryza sativa L.) of F5 and F6 Generation.
Abstrak: Beras merupakan sumber karbohidrat utama masyarakat Indonesia. Peningkatan potensi produktivitas padi untuk mencukupi kebutuhan masyarakat terus dilakukan melalui perbaikan mutu dengan kegiatan pemuliaan tanaman dimana salah satu tahapannya yaitu uji daya hasil pendahuluan. Penelitian ini bertujuan menguji daya hasil dan keragaan galur harapan padi generasi F5 dan F6 untuk memperoleh galur yang memiliki daya hasil dan karakter agronomi lebih baik sebagai galur yang akan diuji pada tahapan berikutnya. Penelitian dilaksanakan pada bulan Februari hingga Juli 2023 di Kebun Percobaan Sawah Baru, Kecamatan Dramaga, Bogor dan Laboratorium Pemuliaan Tanaman. Percobaan menggunakan Rancangan Kelompok Lengkap Teracak faktor tunggal dengan 84 galur dan 2 varietas pembanding sebagai perlakuan. Hanya galur IPB200-F-42 dengan daya hasil nyata lebih tinggi daripada Inpari 32 (4,58 ton ha-1) dengan produktivitas sebesar 7,16 ton ha-1, namun tidak berbeda nyata dengan Ciherang (5,21 ton ha-1) berdasarkan analisis statistik. Meskipun demikian, terdapat galur yang cenderung memiliki produktivitas lebih tinggi daripada varietas pembanding berdasarkan nilai rataan serta memiliki karakter agronomi sesuai dengan kriteria PTB. Galur-galur tersebut yaitu IPB200-F-2, IPB200-F-14, IPB200-F-15, IPB200-F-17, IPB204-E-6, IPB200-F-21, IPB200-F-22, IPB200-F-25, IPB204-E-10, IPB201-F-16, IPB200-F-43, IPB200-F-44, IPB187-F-40-1-1., Rice is the main source of carbohydrates for Indonesian people. Increasing the potential for rice productivity to meet community needs continues to be carried out through quality improvement through plant breeding activities, where one of the stages is preliminary yield testing. This study aims to test the yield and performance of the expected lines of F5 and F6 generations of rice in order to obtain lines that have better yield and agronomic characteristics as lines to be tested in the next stage. The research was conducted from February to July 2023 at the Sawah Baru Experimental Garden, Dramaga District, Bogor, and the Plant Breeding Laboratory. The experiment used a single factor randomized block design with 84 lines and two control varieties as treatments. IPB200-F-42 is the only one line which had significantly higher yields than Inpari 32 (4.58 tons ha-1) with a productivity of 7.16 tons ha-1, but was not significantly different from Ciherang (5.21 tons ha-1) based on statistical analysis. Nonetheless, there are lines that tend to have higher productivity than the control varieties based on the average value and have agronomical characteristics according to the PTB criteria. These lines are IPB200-F-2, IPB200-F-14, IPB200-F-15, IPB200-F-17, IPB204-E-6, IPB200-F-21, IPB200-F-22, IPB200-F-25, IPB204-E-10, IPB201-F-16, IPB200-F-43, IPB200-F-44, IPB187-F-40-1-1.
Keyword: genotype, new plant type of rice, productivity, selection

Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
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