Judul: Morpho-physiological Responses of Cacao Seedlings to The Addition of Papuan Ayamaru Phosphate Rock, Humic Acid, and the Inoculation AM Fungi and Phosphate Solubilizing Bacteria
Abstrak: The purposes of the study were to obtain a humic acid dosage, an arbuscular mycorrhizal fungi (AMF) inoculant, and a phosphate solubilizing bacteria (PSB) isolate for improving the response of cacao seedlings to Ayamaru phosphate rock (APR). The study was conducted in the Cikabayan research garden of IPB. F1 UAH cacao seeds from Coffee and Cacao Research Center, Jember, East Java was used and the seedlings were grown on Ultisol, acid soil from Jasinga in 20 cm x 30 cm sized polybag. The seedlings were grown under 60% of shading net for the period of four months.
Keyword: arbuscular micorrhizal fungi, phospate solubilizing bacteria, acid soil, West Java, East Java

Judul: Respon pertumbuhan bibit karet (Hevea brasiliensis Muell. Arg.) terhadap pemberian inokulan cendawan mikoriza arbuskula dan pemupukan fosfor
Abstrak: The rubber plant is one of the commodities that have significance in the socio-economic aspects of Indonesian society. To increase the production and quality of the rubber must be done with good seeding techniques. This research objective to study the response of Arbuscular Mycorrhizal Fungi inoculants and dose of fertilizer P to the growth of rubber stump (Hevea brasiliensis Muell. Arg). The research was conducted at Cikabayan Experimental Farm from May to August 2014. The experiment designed as a randomized complete block design (RKLT) factorial with two factor and three replications. The first factor was three levels arbuscular mycorrhizal fungi inoculants dosage, i.e. without mycorrhizal inoculants, 10 g per plant, and 20 g per plant. Mycorrhizal inoculants was applied one month after rubber stump planted. The second factor were four level dosage of phosphorus of SP-36 fertilizer (0, 0.5, 1.0, 1.5 dosage recommended that is giving 3.88 g per plant at first month and 7.76 g per plant in the third month). The results showed that arbuscular mycorrhizal fungi inoculants was not significantly difference to length of buds, diameter of buds, number of petiole, number of roots, longest roots, dry weight and wet weight of roots, dry weight and wet weight of shoots. Phosphorus fertilization significantly affect to length of buds, and dry weight and wet weight of roots with linear response pattern. There was an interaction between the giving of arbuscular mycorrhizal fungi inoculants and dosage of phosphorus to length of buds, diameter of buds, and number of petiole. The best combination was 0.5 dosage recommended of SP-36 fertilizer and giving mycorrhizal inoculant 20 g per plant.
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