Judul: Screening of upland rice (Oryza sativa L.) lines derived from anther culture to aluminium tolerance and blast resistance
Abstrak: Aluminium (Al) toxicity and blast disease caused by fungus Pyricularia grisea (Cooke) Sacc. are the most important yield-limiting factors for upland rice production in acid soils. A series of experiment were conducted to screen Al tolerant and blast disease resistance genotypes from doubled haploid (DH) lines derived from anther culture, to examine the contributions of Silicate (Si), Nitrogen (N), and Al accumulation in plant tissue to Al tolerance and resistance to blast disease in upland rice and to evaluate the performance of DH lines in field with Al and without Al toxicity.
Keyword: Pyriculariagrisea(Cooke) Sacc., Haploid ganda, Kultur antera, Akumulaasi silikat, Adaptasi tanaman pada tanah masam, Metode penapisan, Ketenggangan alumunium

Judul: Physiology and Inheritance of Nitrogen Efficiency er Aluminium Stress Condition in Upland Rice (O,yza sativa L.).
Abstrak: Salah satu pendekatan untuk mengatasi kendala pengembangan tanaman padi pada tanah mineral masam adalah menggunakan varietas yang tenggang terhadap keracunan aluminium dan efisien dalam keadaan kekurangan hara. Untuk itu perlu dilakukan pembentukan varietas tersebut melalui program pemuliaan tanaman. Untuk mengawali program ini maka diperlukan berbagai informasi dasar tentang fisiologi dan pewarisan efisiensi hara dalam keadaan cekaman aluminium. Penelitian ini telah melakukan serangkaian percobaan dengan tujuan mengidentifikasi galur padi gogo yang efisien nitrogen dalam keadaan cekaman aluminium, mempelajari mekanisme fisiologi efisiensi nitrogen serta pola pewarisan karakter efisiensi nitrogen pada padi gogo (Oryza sativa L.) dalam keadaan cekaman aluminium. Penelitian ini terdiri dari tiga bagian, yaitu (1) identifikasi galur, (2) studi fisiologi dan (3) studi pewarisan. Dalam identifikasi galur dilakukan penyaringan 150 galur padi gogo bagi ketenggangan terhadap aluminium dengan metode kultur larutan hara Yoshida yang mengandung 45 ppm Al. Tahap selanjutnya adalah melakukan penyaringan galur tenggang Al bagi efisiensi nitrogen dalam keadaan cekaman aluminium. Penyaringan dilakukan dengan metode kultur larutan hara Yoshida yang mengandung 5 ppm N dan 45 ppm Al., An alternative to overcome soil problems for upland rice development acid soil is by growing a variety that tolerant to aluminium toxicity and that efficient to low nutrient availability. Therefore, it is necessary to create the variety through a plant breeding program. The first step of the program is to investigate basic information of physiology and inheritance of nutrient element efficiency under aluminium stress condition. This study conducted some experiments in order to identify nitrogen-efficient upland rice lines, to investigate the physiological mechanisms of nitrogen efficiency and the inheritance of nitrogen efficiency characters under aluminium stress condition in upland rice. The study consisted of three levels, namely: (1) line identification, (2) physiological study, (3) inheritance study. The first step of the line identification was screening 150 upland rice lines (including landrace, breeding lines and cultivars) from various area of Indonesia for aluminium tolerance by the Yoshida nutrient solution culture method with 45 ppm Al. Subsequently, the Al-tolerant lines selected were screened for nitrogen efficiency by the Yoshida nutrient solution culture method with 5 ppm N and 45 ppm Al. In the physiology study, it was grown six upland rice lines differing in nutrient efficiency in four types of stress by the nutrient solution culture thod. At 14 days after planting, the seedling dry weight, nitrogen efficiency ratio (NER), nitrogen utilization efficiency (NUE), net nitrate and net
Keyword: Oryza sativa, Physiology, Nitrogen efficiency, Aluminium stress condition

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology