Judul: Study on the effect of Pup1 (P Uptake1) introgression for increasing rice tolerancy to Phosphorus deficiency
Abstrak: Phosphorus is one of the major nutrient for plant. P-deficiency occurs in most of soil, mostly due to the bounding of P to minerals, such as Ca, Fe, and Al, therefore, P is not available for plants. Rice plant having tolerance to Pdeficiency is very important, because it can decrease the input of P fertilizer, lime, and organic matter. Genes related to P uptake had been mapped (Pup1/P Uptake 1) and some molecular markers for selection purposes have already been developed. Activities for introgression of Pup1 into Indonesian modern rice varieties were conducted to increase the yield and to observe effect of Pup in the Indonesian varieties. Pup1 from Kasalath and NIL-443 was introgressed into Situ Bagendit and Batur, through conventional breeding (backcross method). They are Situ Bagendit x Kasalath, Situ Bagendit x NIL-C443, Batur x Kasalath, and Batur x NIL-C443. Their progenies were selected using molecular markers (spesific markers for Pup1 and SSR markers). This experiments were conducted in Indonesia and IRRI (Philippines) since August 2006 up to June 2009. Development of Pup1 lines were conducted using foreground, recombinant, dan background markers up to BC2F3 lines for each crossing. Based on molecular analysis, genotype condition of Pup1 locus indicated homozygote locus for all of BC2F2 selected lines, and this result was also found in the subsequent generation. Small part of donor segment (Kasalath or NIL-C443) still remaining in the BC2F3 lines in different location, so it will influence plant performance. These donor parent segment were 1.6 – 2.6 % of genome total lenght of rice genome. Testing on BC2F3 lines were performed using 3 methods : nutrient solution (0.5 ppm P and 10 ppm P under 0 ppm Al and 45 ppm Al), Ultisol soil from Kentrong Village (2 kg P/ha and 25 kg P/ha), and field experiment at Taman Bogo, Lampung (no P fertilizer and add P fertilizer). The results showed that many variation of agronomic characters at each BC2F3 lines occurs for each experiment, but effect of Pup1 on agronomic characters can be clearly detected on less P compared with adequate P. Pup1 on BC2F3 lines influenced on the increasing of plant dry weight compared the parent, but tend to decrease on generative phase (especially weight of filled grain/plant), eventhough some lines showed better performance than their parent on both, dry weight and the weight of filled grain/plant. For further experiment, the BC2F3 lines had been selected at Taman Bogo field experiment, Lampung, by individual plant.
Keyword: 

Judul: Improve Selection Method of Rice for Suboptimum Phosphorus
Abstrak: Ketersediaan fosfor (P) yang rendah di tanah masam dan daya beli petani yang rendah merupakan faktor yang menyebabkan permasalahan kekurangan unsur hara P di berbagai wilayah budidaya padi. Pengembangan varietas yang adaptif terhadap kondisi P suboptimum sangat penting untuk meningkatkan produktivitas padi pada wilayah tersebut. Metode seleksi yang efektif merupakan faktor penting dalam program pemuliaan untuk mengatasi permasalahan kondisi P suboptimum. Penelitian ini bertujuan mengembangkan metode seleksi yang efektif untuk menghasilkan galur padi yang adaptif pada kondisi tanah P suboptimum. Kegiatan penelitian dilaksanakan selama empat musim tanam dari bulan April 2012 hingga bulan Desember 2014 di KP Muara, Bogor dan lahan petani di Desa Leuwiliang. Dua kombinasi persilangan digunakan pada penelitian ini yaitu IR6008023/Bemas Prima dan Gampai/Progol. Dua populasi generasi F 3 ditanam pada lingkungan seleksi P suboptimum di KP Muara Bogor, mulai bulan April sampai Agustus 2012 dengan menggunakan metode seleksi bulk. Benih generasi F 4 dipanen dan dibagi empat untuk diseleksi pada lingkungan P optimum (36 kg ha-1 P2O5) dan P suboptimum (tanpa diberi pupuk P) dengan metode pedigree dan bulk modifikasi hingga generasi F 5• Dari setiap populasi, metode seleksi dan lingkungan seleksi dipilih 40 tanaman untuk dievaluasi pada generasi F6• Evaluasi generasi F6 dilakukan di lahan petani Desa Leuwiliang, Jawa Barat dari bulan Juli sampai Desember 2014. Populasi generasi F6 ditanam pada lingkungan produksi P optimum dan P suboptimum menggunakan rancangan augmented., The low availability of phosphorus (P) in acid soils and low purchasing power of farmers is a factor that led to the problem of P deficiency in different rice cultivation areas. The development of varieties that are adaptive to P sub-optimum condition is important to increase the productivity of rice in the region. Effective selection method is an important factor in breeding programs to overcome the problems of P sub-optimum conditions. This research aimed to develop an effective selection method to produce rice lines that are adaptive to the sub-optimum P conditions. The research was carried out during four seasons from April 2012 to December 2014 in Muara Experimental Farm, Bogor and farmers' land in the Leuwiliang village. Two cross combinations were used in this research i.e IR6008023/Bernas Prima and Gampai/Progol. Two populations of F3 generations were planted in the sub-optimum P selection environment in Muara Experimental Farm, Bogor from April to August 2012 using bulk selection method. The F 4 generation seed were harvested and split into four to be selected at the optimum P environment (36 kg ha-1 P2O5) and sub-optimum P (without P) with pedigree and bulk modified methods until F5 generation.
Keyword: bulc modification, pedigree selection method, rice, selection environment, Rice Cultivation, Acid Soils, Adaptasi Tanaman, Plant Biotechnology, Rice Productivity, production environment, optimum and suboptimum phosphor

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular