Judul: Pertumbuhan Protocorm Like Bodies (Plb) Dua Populasi Hasil Persilangan Anggrek Phalaenopsis pada Beberapa Komposisi Media
Abstrak: In vitro propagation of orchids had shortened the time required to produce plants in large quantities. The objective of this research was to determine the effect of medium composition on the growth of protocorm like bodies (Plb) of two populations of Phalaenopsis hybrid. Research laid out in completely randomized design with two factors, namely the Phalaenopsis hybrid populations and medium composition. The first hybrid of population was generated from a crossing between the white standard and the pink standard of Phalaenopsis hybrid accession and the second hybrid was the reciprocal of the first crossing. Seeds were germinated on MS 1/2 to produce Plb, then the Plb subsequently cultured in four media composition, i.e MS 1/2 , MS 1/2 + coconut water 150 ml l-1, complex fertilizer Hyponex (2 g l-1), and Hyponex (2 g l-1) + coconut water 150 ml l-1. The results showed that the increase of Plb was significantly influenced by population, medium composition, and the interaction between the two factors. Population 1 showed better growth (average 5.4 Plb per 16 weeks) compared with the population 2 (average 2.2 Plb per 16 weeks). The best medium for the growth of Plb into plantlets in both populations is Hyponex (2 g l-1) or Hyponex (2 g l-1) + coconut water 150 ml l-1.
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Judul: Pengaruh komposisi media dalam pertumbuhan protocorm like bodies, planlet, dan aklimatisasi phalaenopsis amabilis
Abstrak: Phalaenopsis amabilis, known as ‘anggrek bulan’, is one of the most popular kind of orchids and was inaugurated as one of the national flower as 'Puspa Pesona'. The purpose of this study was to determine and study the effects of various tissue culture media composition on Protocorm Like Bodies (PLBs) multiplication, growth of plantlets, and acclimatization of Phalaenopsis amabilis. Basic medium used was a half strengh of Murashige and Skoog (1/2MS) and Hyponex (Hyp) with additional coconut water (CW), benzylaminopurine (BAP), and chitosan. In PLBs multiplication experiments, ½ MS + 15% CW medium produced the highest percentage of survival rate. Treatment with ½ MS + 15% CW medium and Hyp. 2 g/l + 15% CW + 2.5 ppm chitosan medium gave the best effect on the fresh weight of plantlets. The composition of the culture medium significantly affect the fresh weight and length of root on 8-WAP(week after planting) in the acclimatization stage.
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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