Judul: Respon Fisiologi Tanaman Jagung dan Cabai Terhadap Aplikasi Pupuk Organik yang Diperkaya dengan Pupuk Hayati pada Dua Lokasi Pengujian yang Berbeda.
Abstrak: It was known that biofertilizer can improve plant growth and production. The aim of this research was to study the influence of organic fertilizer enriched by biofertilizer on maize (Zea mays L.) and chili (Capsicum annum L.) planted in Bogor (West Java) and Kubu Raya (West Kalimantan). This research was conducted by using randomized block design with two factors. The first factor was the NPK fertilizer doses, which were 0%, 50%, and 100% of recommended dose. The second factor was different type of organic fertilizers, which were without compost, compost, and compost enriched with biofertilizer. Growth and production of both maize and chili increased in Kubu Raya as well as in Bogor. In combining with enriched compost, there was no significally different effect between NPK dose of 50% and 100%. The result showed that enriched compost was able to reduce the use of NPK fertilizer up to 50%. Production of maize in Kubu Raya was higher than that of in Bogor, while the chili production was higher in Bogor than that of Kubu Raya. Enriched compost affected leaf chlorophyll content of maize in Kubu Raya and Bogor, but it had no effect on vitamin C content of chili and total sugar content of maize planted in both locations.
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Judul: Kombinasi antara Pupuk Hayati dan Sumber Nutrisi dalam Memacu Serapan Hara, Pertumbuhan, serta Produktivitas Jagung (Zea mays L.) dan Padi (Oryza sativa L.)
Abstrak: The continues utilization of anorganik fertilizer might result in depletion of soil fertility. The objective of this research was to evaluate the effect of biofertilizer and nutrient sources in improving nutrient uptake, growth and productivity of maize and rice. The experiment was conducted in the plastic house Cikabayan IPB Farm for maize, while for rice it was held in a green house of Balai Besar Biogen Cimanggu, Bogor, West Java. Randomized Block Design was used for experimental design using 2 X 4 factors with 5 replications. The first factor is biofertilizer treatment which consist of application of biofertilizer (H1) and without biofertilizer as control (H0). The second one is the type of nutrient sources that comprise of 4 levels: Soil (N0), Soil + 100 % dosage of anorganik fertilizer (N1), Soil + 100 % dosage of compost (N2), Soil + 50 % dosage of compost + 50 % dosage of anorganic fertilizer (N3). The biofertilizer consist of Azospirillum sp., Pseudomonas sp., and Bacillus sp. selected by the Laboratory of Mikrobiologi, Bogor Agricultural University, Darmaga, Bogor, West Java. Each isolate was enriched in broth medium with the population of 108 cell/ml. The dosage of biofertilizer was 15 ml per pot. The dosage of anorganic fertilizer was 250 kg/ha Urea; 200 kg/ha SP-36, and 200 kg/ha KCl, whereas the compost dosage was 10 ton/ha. The result showed that application of biofertilizer significantly improved nutrient uptake, growth and productivity of rice and maize. For maize, the application of biofertilizer increased macronutrient uptake by 50-97 %, micronutrient uptake by 58,9-63,2 %, dry weight of plant up to 53,7 %, and dry weight of seed up to 36,6 %. For rice, application of biofertilizer resulted in an increase of macronutrient uptake by 10,9-22,5 %, plant dry weight 11,6 %, and total weight of rice seed 7,2 %. The result also showed that the nutrient sources significantly affect the nutrient uptake, growth and productivity of maize and rice. In maize, the highest macronutrient and micronutrien uptake (4,5 g/pot and 10,4 mg/pot respectively) and dry weighy of seed (36,6 g/pot) resulted from the treatment of N2, while the highest dry weight of plant resulted from N3 (6,9 g/pot). For rice, N2 treatment had the maximum macronutrient uptake (2,7 g/pot). The highest micronutrient uptake (5,9 mg/pot), dry weight of plant (41,4 g/pot), and total weight of rice seed (32,8 g/pot) resulted from the treatment of N3. In maize, the N2 treatment in combination with biofertilizer resulted in the highest seed dry weight (41,6 g/pot) and increased productivity by 97-137 % as compared to the treatment of N1 and N3. In rice, the combination treatment of N3 and biofertilizer resulted in the highest weight of rice seed (33,4 g/pot) as compared to the others.
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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