Judul: Pertumbuhan Anggrek Phalaenopsis amabilis pada Perlakuan Chitosan dan Asam Salisila
Abstrak: Phalaenopsis orchid plant vegetative growth is influenced by environmental condition such as light, temperature, and humidity. Certain organic material affected on the growth, development and plant resistance to pests and diseases, including chitosan and salicylic acid. The objective of this research was to test the application of organic compound chitosan and salicylic acid on the growth of Phalaenopsis amabilis. This research was arranged in a randomized completely design with organic compound as a single factor. There were six treatment, 3 ppm chitosan, chitosan 6 ppm, 5 ppm salicylic acid, salicylic acid 10 ppm and 3 ppm chitosan + 5 ppm salicylic acid. Each treatment was repeated five times with 3 plantlets per bottle. Organic compound were mixed in ½ MS in vitro medium and planlets were transfered to the treatment medium and cultured in the tissue culture laboratory for four weeks. Planlets subsequently were acclimatizated to spaghnum ii moss medium in greenhouse. Treatment were continued by spraying of organic compound to planlets every two weeks. The results of the experiment showed that the best treatment of organic compound, was chitosan 3 ppm. This is showed by length of youngest leaf and percentage growth of plant on treatment of chitosan 3 ppm.
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Judul: Pengaruh Pupuk Organik Guano dan Chitosan terhadap Pertumbuhan dan Perkembangan Anggrek Phalaenopsis spp.
Abstrak: This research was conducted to determine the effect of organic fertilizer guano and chitosan on the growth and development of phalaenopsis orchid conducted in the Gunung Batu nursery, Bogor in March until August 2011. This research used a completely randomized block design with 4 treatments and 4 replications. Fertilizer treatments consisted of Thaichung fertilizer 1 g /l, Thaichung fertilizer 1 g/l + chitosan 10 ppm, Thaichung fertilizer 1 g/l + guano 10 ml / l, and Thaichung fertilizer 1 g/l + chitosan 10 ppm + guano 10 ml / l. Thaichung fertilizer 1 g/l were needed for P. bellina and P. modesta, and guano 10 ml/l were needed for P. amabilis in compot in the hot and dry conditions.
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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