Judul: Respon Morphophysiology and Consumptif Water Requirement of Paddy at Anorganik and Organik Fertilizer
Abstrak: Prioritas pembangunan pertanian untuk memenuhi kebutuhan pangan nasional semakin meningkat seiring peningkatan jumlah penduduk. Peningkatan produksi padi salah satunya dengan penggunaan pupuk anorganik, namun penggunaan yang terus menerus memicu terjadinya degradasi lahan dan air. Pupuk organik merupakan salah satu solusi untuk memperbaiki kondisi tersebut. Penelitian bertujuan untuk menganalisis perbedaan morfofisiologi dan efisiensi pemakaian air padi Inpari 33 pada pemupukan anorganik dan organik. Penelitian dilaksanakan pada bulan Juli - Desember 2020 di IP2TP Sukamandi Balai Besar Penelitian Tanaman Padi Subang Jawa Barat. Rancangan percobaan yang menggunakan Split Plot design dangan tiga ulangan. Petak utama adalah pupuk anorganik yang terdiri dari perlakuan tanpa NPK (kontrol), tanpa N (PK), tanpa K (NP), tanpa P (NK) dan NPK. Anak petak yaitu pupuk organik terdiri dari pupuk kandang sapi (pukan), kompos jerami dan tanpa organik. Hasil percobaan menunjukkan perlakuan pupuk anorganik tanpa P, tanpa K dan NPK meningkatkan pertumbuhan jumlah anakan sebesar 44-49%, nilai SPAD 6,9-10,98%, produksi 23- 51% dibandingkan perlakuan tanpa pupuk NPK dan tanpa N. Perlakuan pupuk anorganik tidak mempengaruhi laju fotosintesis namun mempengaruhi konduktansi stomata dan serapan hara. Efisiensi pemakaian air tertinggi yaitu 1,17 g gabah L-1 pada perlakuan tanpa P. Aplikasi pupuk organik belum mampu meningkatkan pertumbuhan, hasil, fotosintesis dan efisiensi penggunaan air. Konduktansi stomata dapat ditingkatkan dengan aplikasi pukan. Kebutuhan air konsumtif rata-rata tanaman padi selama penelitian adalah 469,48 mm dengan koefisien evapotranspirasi rata-rata sebesar 1,18. Interaksi pupuk anorganik dan organik mempengaruhi jumlah anakan, jumlah malai per rumpun, berat 1000 butir, serapan hara dan total evapotranspirasi. Penambahan pupuk kandang sapi sangat mempengaruhi jumlah anakan dan total evapotranspirasi pada perlakuan tanpa pupuk P. Penambahan bahan organik baik pupuk kandang maupun kompos jerami dapat mengurangi laju evaporasi dari dalam tanah. Kondisi tanaman yang tidak di pupuk P maka penambahan bahan organik dapat meningkatkan serapan hara P pada tanaman untuk tanah dengan karakteristik kandungan P potensial sedang sampai tinggi. Perlakuan kompos jerami mempunyai nilai efisiensi agronomis nitrogen mencapai 13,66., The priority of agricultural development is to supply national food in line with the increasing population. One of the ways to enhance rice production is to apply inorganic fertilizers, but the application of inorganic fertilizer in the long term causes soil and water degradation. The organic fertilizer would restore the soil condition. This research aims to determine differences in morphology rice Inpari 33 and water use efficiency in treatments inorganic and organic fertilization. The research was conducted from July to December 2020 in IP2TP Sukamandi, Indonesian Center for Rice Research, Subang-West Java. The treatments were Split Plot Design with three replications. The main plot was inorganic fertilizers, namely no application fertilizer of NPK, N, K, P, and NPK fertilizer. Sub-plots were organic fertilizers consisting of manure, straw compost, and non-organic fertilizers. The research result showed that inorganic fertilizers increased the number of tillers by 44-49%, SPAD value 6,9-10,98%, rice production 23-51%, water use efficiency 1.17% on minus P treatment. The treatment of inorganic fertilizers did not affect the rate of photosynthesis but did affect stomatal conductance and nutrient uptake. The highest efficiency of air use was 1.17 g of L-1 grain in the treatment without P.
Keyword: compost, evapotranspiration, photosynthesis, manure, stomata conductance

Judul: Increased Rice Yield (Oryza sativa L.) with Application of Organic Fertilizer Enriched with Microbes
Abstrak: Produktivitas padi Indonesia beberapa tahun terakhir mengalami penurunan. Pemupukan yang sesuai dengan kondisi tanah dan kebutuhan tanaman mampu meningkatkan produksi tanaman. Aplikasi pupuk organik diperkaya dapat meningkatkan kesuburan tanah. Mikroba yang hidup di perakaran tanaman atau PGPR dalam pupuk dapat meningkatkan ketersediaan hara dalam tanah dan mensintesis hormon pertumbuhan tanaman melalui aktivitas biologisnya. Penelitian ini bertujuan untuk mempelajari pengaruh aplikasi pupuk organik diperkaya terhadap peningkatan hasil padi sawah dan pengurangan dosis pupuk anorganik. Rancangan yang digunakan adalah rancangan kelompok lengkap teracak satu faktor yaitu dosis pupuk dengan 4 ulangan. Penelitian dilaksanakan di Kebun Pendidikan Sawah Baru IPB. Analisis tanah dan analisis kandungan pupuk dilaksanakan di Laboratorium Kimia dan Kesuburan Tanah, Departemen Ilmu Tanah dan Sumber Daya Lahan, Laboratorium Pengujian Departemen Agronomi dan Hortikultura, serta Laboratorium Tanah, Tanaman, Pupuk, Air, Balai Penelitian dan Pengembangan Pertanian. Pelaksanaan penelitian dimulai pada November 2020 hingga April 2021. Pengamatan dilakukan terhadap pertumbuhan, hasil, dan komponen hasil padi sawah. Hasil penelitian ini menunjukkan aplikasi pupuk organik diperkaya secara umum tidak meningkatkan pertumbuhan dan hasil per tanaman maupun hasil per hektar padi sawah. Aplikasi pupuk organik diperkaya dapat mengurangi 25% penggunaan pupuk anorganik dengan nilai efektivitas agronomi relatif sebesar 108,8%., Rice productivity in Indonesia has decreased in recent years. Fertilization that is suitable for soil conditions and plant needs can increase crop yield. The application of bioorganic fertilizer would be able to increase soil fertility. Microbes that live in plant roots could increase the availability of nutrients in the soil and synthesize plant growth hormones through their biological activities. The research aims to study the effect of the application of organic fertilizer enriched with microbes on increasing growth, yield, and yield components of lowland rice and the reduction of the dose of inorganic fertilizer. The experimental design used was a randomized complete group design with one factor, namely the dose of fertilizer with 4 replications. The research was carried out at the Sawah Baru Teaching Farm, IPB. Soil analysis and analysis of fertilizer content were carried out at the Laboratory of Chemistry and Soil Fertility, Department of Soil Science and Land Resources, Testing Laboratory of the Department of Agronomy and Horticulture, and the Laboratory of Soil, Plants, Fertilizer, Water, Agricultural Research and Development Center. The experiment was conducted from November 2020 until April 2021. The observations made were observations of vegetative and generative characters, as well as yields. Results shows, the application of enriched organic fertilizers did not increase growth and yield per plant or yield per hectare of lowland rice. Application of enriched organic fertilizers, however, could reduce 25% of inorganic fertilizers usage with a relative agronomic effectiveness value of 108.8%.
Keyword: effectiveness, organic fertilizer, PGPR, rice, yield

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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