Judul: Pemanfaatan pupuk organik dan pupuk hayati dalam peningkatan produksi buncis mini dan perbaikan kualitas tanah
Abstrak: Conventional vegetable growers use only anorganic fertilizers. Using anorganic fertilizers only for long period of time, has negative impact on soil properties, hence soil degradation can not be avoided. Since the last few years, demand for healthy vegetable which is free from agrochemicals such as pesticide is increasing significantly. The objectives of the experiments were (i) to evaluate the effect of 3 kinds of organic fertilizers and 2 kinds of biofertilizers on vegetative growth and yield of french bean, (ii) to evaluate the effect of combination between organic fertilizer and biofertilizer at different rates of anorganic fertilizers on vegetative growth, yield of french bean and soil quality. This study consisted of two experiments. The first experiment was arranged on Randomized Complete Block Design with 2 factors, the first factor was organic fertilizer consisted of; chicken, goat, and cow manure. The second factor was biofertilizer consisted of: Control, Biost, Azozo. The result showed that the highest yield of french bean was achieved at chicken manure application produced greater in pod weight per plot 14.93% higher than goat manure and 23.66% than cow manure. The second experiment used Split Plot experiment that was arranged in Randomized Complete Block Design with 4 replications. Two applications the combination between organic fertilizer and biofertilizer as the main plot and 4 anorganic fertilizer rates 0%, 50%, 100% and 150% as sub plot. The result showed that the application between chicken manure and Azozo produced more pod weight per plot 58.9% higher than the application without the combination chicken manure and Azozo. Pod weight per plot from 50% rates of anorganic fertilizer produced 20.5% higher than 100% rates of anorganic fertilizer. Anorganic fertilizers can be substituted by organic fertilizers and biofertilizers for greater soil quality and sustainability of the crop productivity.
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Judul: Pengaruh Pemberian Pupuk Organik pada Produksi dan Serapan Hara Jagung Manis (Zea mays) di Latosol, Darmaga
Abstrak: There are two form of organic fertilizers, solid and liquid. Solid organic fertilizer is usually applied to the soil. The advantage in application of organic fertilizers able to adsorb nutrients that easily lost and supply availability of nutrients and therefore can increase efficiency of fertilizer. The purpose of this study was to study the effect of organic fertilizer application on Latosol, Darmaga to production and nutrient uptake of corn as plant indicator. The experiment was conducted in the greenhouse by using completely randomized design consisting of seven treatments and each treatment was repeated four times so that there were 28 pot experiments. Seven treatments were consisted of control, standard, 75% PO + 50% S, 75% PO + 75% S; 100% PO + 50% S; 100% PO + 75% S, and 125% PO + 50% S. The parameters measured were plant height, weight of shoot, root weight, ear weight with and without cornhusk, uptake of N, P, and K nutrients in shoot and plant roots and the Corganic content, N-total, and CEC (cation exchange capacity) soil after the experiment. The result of experiment showed that the application of organic and anorganic (standard) fertilizer on plant height and weight of shoot was not significantly different than standard fertilizer (100% S). The weight of plant roots and nutrient uptake of N, P, and K of the shoot and plant roots in the treatment of 100% PO + 75% S was significantly higher than other treatments. Treatment combination of organic and anorganic (standard) fertilizer at the lower doses of standard recommendation significantly increased ear weight with and without cornhusk. Dosage recommendations based on the RAE value are the treatment of 100%PO + 50%S (158,66%) and 75%PO + 50%S (142,52%). The analysis of soil after the experiment showed that the use of organic fertilizer combined with anorganic fertilizer (standard) produced levels of C-organic, N-total, and the CEC soils tend to be higher than the standard (100% S) and control treatments. The use of organic fertilizer combined with anorganic (standard) fertilizer at lower doses (50% S and 75% S) increased effectiveness of fertilizer to increase the growth and production of corn.
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Judul: Invers Drazin dari Matriks Toeplitz Singular
Abstrak: Matriks Toeplitz adalah matriks yang setiap unsur pada diagonal utama bernilai sama dan setiap unsur pada subdiagonal yang bersesuaian dengan diagonal utama juga bernilai sama. Matriks singular adalah matriks yang tidak bisa ditentukan inversnya. Akan tetapi, dapat diupayakan untuk ditentukan inversnya menggunakan invers matriks yang diperumum. Invers Drazin merupakan salah satu jenis invers matriks yang diperumum. Pada karya ilmiah ini ditentukan invers Drazin dari matriks Toeplitz singular dengan menggunakan metode Leverrier Faddeev. Kemudian, ditentukan invers Drazin dari matriks Toeplitz singular yang direpresentasikan sebagai penjumlahan segitiga bawah dan segitiga atas matriks Toeplitz berdasar pada teorema Gohberg dan Semencul., Toeplitz matrix is a matrix in with element on the main diagonal has the same value and on the subdiagonal corresponding to the main diagonal also has the same value. Singular matrix is a matrix that has no inverse. However, it can be attempted to determine the inverse using a generalized inverse matrix. Inverse Drazin is a type of generalized matrix inverse. This paper discussed the inverse Drazin for a singular Toeplitz matrix using the Leverrier Faddeev method. Then, the Drazin inverse of the singular Toeplitz matrix which is represented as a sum of products of lower and upper triangular Toeplitz matrix based on Gohberg and Semencul theorem.
Keyword: inverse Drazine, singular Toeplitz matrix