Judul: The Effect of Actinobacteria Consortium, Carrier Materials, and NPK Fertilizers on the Growth of Rice Plants
Abstrak: Kebutuhan akan beras mengalami peningkatan seiring dengan kenaikan jumlah penduduk, sehingga perlu dilakukan peningkatan produksi untuk menjamin ketersediaannya. Peningkatan produktivitas padi dapat dilakukan melalui pemupukan yang tepat dan berimbang. Bio-inokulan aktinobakteri yang diformulasikan dengan bahan pembawa dapat meningkatkan pertumbuhan dan perkembangan tanaman karena kemampuannya sebagai bakteri pemacu pertumbuhan tanaman. Penelitian ini bertujuan menganalisis pengaruh penggunaan bio-inokulan aktinobakteri yang diformulasi dengan bahan pembawa gambut atau zeolit, serta pupuk NPK pada pertumbuhan tanaman padi. Penelitian ini berdasarkan pada Rancangan Acak Kelompok yang terdiri dari 18 perlakuan dan tiga ulangan, yaitu berupa kombinasi antara pemberian konsorsium aktinobakteri (dilakukan dan tidak dilakukan penambahan), jenis carrier (zeolit, gambut, dan kombinasi) dan dosis pupuk NPK (0 g/pot, 0,375 g/pot, dan 0,75 g/pot). Perlakuan penambahan konsorsium aktinobakteri, kombinasi gambut-zeolit 1:3, dan pupuk NPK dosis 0,75 g/pot (A2C3P3) memberikan hasil yang konsisten dalam meningkatkan hasil rata-rata parameter vegetatif dan reproduktif tanaman padi yang diamati di rumah kaca. Perlakuan A2C3P3 memberikan pengaruh nyata pada jumlah anakan, lebar daun bendera, bobot kering akar dan tajuk padi yang diamati pada umur 10 MST dibandingkan dengan kombinasi perlakuan lainnya., The high demand for rice is due to the increasing population. Therefore it is necessary to increase rice production to ensure its availability, through proper and balanced fertilization. Actinobacterial bioinoculum formulated with carriers can enhance plant growth and development due to their ability as plant growth promoting bacteria. This study aims to analyze the effect of using actinobacterial bio-inoculants formulated with peat or zeolite carrier materials, as well as NPK fertilizer on the growth of rice plants. This study was based on a randomized block design consisting of 18 treatments and three replications, namely in the form of a combination of actinobacterial consortium administration (added and not added), type of carrier (zeolite, peat, and combination) and doses of NPK fertilizer (0 g/ pot, 0.375 g/pot, and 0.75 g/pot). The addition of actinobacteria consortium, peat-zeolite combination 1:3, and NPK fertilizer at a dose of 0.75 g/pot (A2C3P3) gave consistent results in increasing the average yield of rice vegetative and reproductive parameters observed in the greenhouse. The A2C3P3 treatment had a significant effect on the number of tillers, width of flag leaf, dry weight of roots and shoots of rice observed at 10 WAP compared to other treatment combinations.
Keyword: actinobacteria, in planta, NPK, peat, zeolite

Judul: The Effect of ZeomicAgro Soil Ameliorant on the Productivity of Rice on Sawah Baru Experimental Field Dramaga
Abstrak: Perbaikan kesuburan tanah dan peningkatan efisiensi penggunaan pupuk anorganik penting diupayakan dalam meningkatkan produktivitas pertanian, antara lain dengan penambahan bahan pembenah tanah. Salah satu pembenah tanah adalah ZeomicAgro yang berbahan dasar zeolit, bahan humat, dan kapur. Tujuan dari penelitian ini untuk mengetahui pengaruh pemberian ZeomicAgro terhadap sifat kimia tanah, pertumbuhan dan produktivitas padi. Penelitian dilakukan di Kebun Percobaan Sawah Baru, dengan jenis tanah Latosol, dan menggunakan benih padi IPB 3S. Penelitian dilakukan menggunakan rancangan acak lengkap (RAL) non faktorial dengan lima perlakuan dan empat ulangan. Perlakuan merupakan kombinasi dosis ZeomicAgro dan pemupukan, dengan P1 (kontrol, tanpa ZeomicAgro dan tanpa pupuk), P2 (pemupukan standar, tanpa ZeomicAgro, Urea 200 kg/ha, SP-36 100 kg/ha, dan KCl 100 kg/ha), P3 (ZeomicAgro 100 kg/ha, Urea 100 kg/ha, SP-36 75 kg/ha, dan KCl 75 kg/ha), P4 (ZeomicAgro 200 kg/ha, Urea 100 kg/ha, SP-36 75 kg/ha, dan KCl 75 kg/ha), P5 (ZeomicAgro 300 kg/ha, Urea 100 kg/ha, SP-36 75 kg/ha, dan KCl 75 kg/ha). Hasil penelitian menunjukkan bahwa perlakuan ZeomicAgro dosis 200 kg/ha nyata meningkatkan kadar Corganik, NO3 - , P-tersedia dan K-dd, serta cenderung meningkatkan N-total dan KTK. Pemberian ZeomicAgro berpengaruh nyata terhadap tinggi tanaman dan jumlah anakan pada umur tanaman 9 MST, serta meningkatkan jumlah anakan produktif. Perlakuan ZeomicAgro dengan dosis 200 kg/ha dapat mengurangi dosis pemupukan urea hingga 50 %, pupuk SP36 dan KCl hingga 25%, dengan tingkat produktivitas tidak berbeda nyata dengan perlakuan standar., Improving soil fertility and increasing the efficiency of using inorganic fertilizers are important efforts to increase agricultural productivity, including by adding soil ameliorant. One soil ameliorant is ZeomicAgro which is made from zeolite, humic substance and lime. The aim of this research is to determine the effect of ZeomicAgro on the growth and productivity of rice. The research was carried out at the Sawah Baru, IPB Experimental Field, with Latosols soil type, and using IPB 3S rice seeds. The research was conducted using a non-factorial completely randomized design (CRD) with five treatments and four replications. The treatment was a combination of ZeomicAgro doses and fertilization, with P1 (as a control, without ZeomicAgro and fertilizer), P2 (standard fertilization, without ZeomicAgro, Urea 200 kg/ha, SP-36 100 kg/ha, and KCl 100 kg/ha), P3 (ZeomicAgro 100 kg/ha, Urea 100 kg/ha, SP-36 75 kg/ha, and KCl 75 kg/ha), P4 (ZeomicAgro 200 kg/ha, Urea 100 kg/ha, SP-36 75 kg/ ha, and KCl 75 kg/ha), P5 (ZeomicAgro 300 kg/ha, Urea 100 kg/ha, SP-36 75 kg/ha, and KCl 75 kg/ha). The results showed that ZeomicAgro treatment with a dose of 200 kg/ha (P4) significantly increased levels of organic-C, NO3 - , available-P and exchangeable-K, and tended to increase totalN and CEC. The application of ZeomicAgro had a significant effect on plant height and number of tillers at 9 WAP, as well as increasing the number of productive tillers. ZeomicAgro treatment with a dose of 200 kg/ha can reduce the doses of urea fertilizer by up to 50%, SP36 and KCl fertilizer by up to 25%, with productivity levels not significantly different from standard treatment.
Keyword: Bahan Humat, Efisiensi pemupukan, latosol, Zeolit, IPB 3S, Fertilizer efficiency, humic substance, IPB 3S, Latosols, zeolite

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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