Judul: Efektivitas Cendawan Mikoriza Arbuskula pada Coating Benih Selama Penyimpanan dan Serapan Hara P Tanaman Jagung Manis
Abstrak: The aim of this study was to find out 1) the effect of adhesive on corn seed quality and arbuscular mycorrhizal fungus (AMF) viability during storage, and 2) the effect of AMF coating method and fertilization P on uptake nutrient P, growth and production of sweet corn plants. This study is devided into two experiments: 1) The effect of adhesive on corn seed quality and AMF viability during storage and 2) The effect of AMF coating on the availability of P, growth, and production of corn plants. The first experiment used Split Plot Design with randomized complete. The first factor is storage period (0, 4, 8, 12, 16 weeks) as the main plot and the second factor is adhesive formulation (without coating, sodium alginate + AMF, gum arabic + AMF, and tapioca + AMF) as subplot. The seconds experiment was done using randomized complete block design with two factors. The first factor is the adhesive formulation (without AMF coating, sodium alginate + AMF, gum arabic + AMF, and tapioca + AMF) and the second factor is the dose of P2O5 fertilizer (no fertilizer, 60 kg ha-1 P2O5, and 120 kg ha-1 P2O5). The results showed that seed coating with sodium alginate, gum arabic, and tapioca gave the same effect on the seed germination. The seed germination decreased significantly at 12 weeks after the storage. In the germination speed, the effect of gum arabic and tapioca same with control, whereas germination speed of sodium alginate was lower. The best adhesive to maintaining the germination of AMF was sodium alginate. The germination of AMF can be maintained up to 16 weeks by 70%. Treatment seed coating with tapioca showed that highest Pavailable in the planting medium, P-content in the seed, and AMF infection in the roots after corn is harvested.
Keyword: 

Judul: Pelapisan Benih menggunakan Bakteri Probiotik untuk Mempertahankan Viabilitas Benih Jagung Manis (Zea mays saccharata Sturt.) selama Penyimpanan
Abstrak: This research aims to evaluate the effect of seed coating by Bacillus subtilis, Serratia marcescens, and Fluorescent Pseudomonads to sweet corn seed (Zea mays saccharata Sturt.) during storage. Research was conducted on nested plot design (Nested Design) with the main plot was the storage period ( 0, 3, 6, 9, 12, 15, 18, 21, and 24 week), and the subplot was the coating treatment ( control, Bacillus subtilis, Serratia marcescens, and Fluorescent Pseudomonads). Interaction of seed coating treatment and seed storage period showed significant effect to seed germination, seed vigour index, dry weight normal seedling, seed moisture content, and population of bacteria. The dry weight normal seedling of seed that was coated by bacteria showed the better dry weight normal seedling result than control seeds. Bacillus subtilis can maintain the seed germination up to 64.0%. Serratia marcescens can maintain the seed germination up to 60.0%, while control seed only have 56.7% seed germination. Based on seed germination result seed coating using Bacillus subtilis and Serratia marcescens are the treatment that more potential to be developed. Bacillus subtilis bacteria showed the best ability to survive until 24 week storage period. The population on Bacillus subtilis until 24 week storage period is 14.2 × 104 cfu g-1.
Keyword: 

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