Judul: Ekspresi Gen PR1 dan PBZ1 yang terlibat dalam Sistem Toleransi Tanaman Padi terhadap Penyakit Blas (Isolat 173)
Abstrak: Pathogenesis Related 1 (PR1) and Pathogenesis Related 10 (PBZ1) genes are involved in the rice defense system against pathogen attack. The aim of this research is to analyze the expression of both genes on rice infected by Pyricularia grisea (isolat 173). The first step of this research was the analysis of virulence of P. grisea isolat 173B and 173M. The highest virulent isolat was subsequently used to analyze the resistance of five rice varieties (Cisokan, IR64, Krueng Aceh, Kencana Bali and Cirata). The second step was the analysis expression of the PR1 and PBZ1 genes in rice infected by P. grisea. The gene expression analysis was based on PCR method by using cDNA as the template and spesific primer. Result of this research showed that isolat 173M has higher virulence than 173B, so the isolat 173M then was used as inoculum to infect the rice for resistance analysis of five rice varieties against P. grisea and the analysis of genes expression. The analysis of resistance varieties of rice showed that Kencana Bali and Cirata were susceptible, IR64 was resistant, while Krueng Aceh showed the moderate susceptibility and Cisokan was moderate resistant against isolat 173M. The analysis of expression of PR1 and PBZ1 genes was carried out in Cisokan as a moderate resistant and Kencana Bali as susceptible varieties. The expression of PR1 and PBZ1 genes were induced by pathogen attack. The induction of PR1 gene expression in Kencana Bali was detected on 7th day after infection, while in Cisokan on 3rd day after infection. On the other hand the induction of PBZ1 gene expression in Kencana Bali was detected on 3rd until 7th day after infection, while in Cisokan at 1st until 7th day after infection. In control plants, both PR1 and PBZ1 genes were not expressed. This result indicate, that the expression rate of PR1 and PBZ1 genes has an important role in the tolerance system of rice to P. grisea.
Keyword: Oryza sativa, Pyricularia grisea, Expression, Uji Virulenssi

Judul: Resistance Test toward of 48 Lines Rice to Blast Disease (Pyricularia oryzae) Race 001
Abstrak: Blast disease, caused by Pyricularia oryzae Cav., is one of the major fungal diseases infected rice (Oryza sativa L.) in Indonesia. The aim of this research was to examine the resistance of rice from the infection of P. Oryzae race 001 and to detect the existance of Pi-ta gene in resistant lines of rice. Resistance evaluation to blast disease (Pyricularia oryzae) on Cisadane (resistant), Kencana Bali (susceptible) as control, and 48 lines of rice was carried out in the green house by using injection inoculated method with P. oryzae race 001. Rice seedling were planted on sterilize soil, and sixteen days old of rice were soaked in the fungal spore suspension (105 spores/ ml) in the dark for 24 hours, and moved to the light. Rice disease was observered on 7-9th days after infection. There were 2 step screening of blast-resistant, which screening I performed a total of three replicates and screening II performed from selected plant in screening I a total of two replicates for each line of rice, with 10 plants in each replication. The result of second screening at green house showed that 13 lines resistant to P. oryzae 001 were IPB140-F-2-1, IPB115-F-4-2-2, IPB113-F-2-2, IPB107-F-7-3, IPB140-F-5, IPB149-F-2, IPB149-F-8, Martapura, IPB149-F-4, IPB149-F-5, IPB113-F-1, IPB102-F-92-1-1, IPB107-F-5-1 with the percentage of resistance ≥ 80 %. Two pairs of DNA primers specific to the dominant indica Pi-ta gene were designed from DNA sequence in gene bank with accession number AF207842 to amplify the Pi-ta DNA fragments by polymerase chain reaction (PCR) method. The results revealed that all of 13 resistant and 2 susceptible lines (IPB107-F-18-4-2 and IPB107-F-16E-6) of rice carrying Pi-ta genes, even in Kencana Bali. The previous experiment shown that Kencana Bali does not have Pi-ta resistance gene. It is expected that Kencana Bali has deletion of Pi-ta resistance gene in the end part of exon 2. Further more, those results also indicated that Pi-ta gene did not confer resistance to race 001 of Pyricularia oryzae. Resistance to P. oryzae race 001 might be controlled by different resistant gene.
Keyword: 

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