Judul: Genetic Information Mapping of Helicoverpa armigera Nucleopolyhedrovirus DNA Polymerase Gene from Bogor Isolate
Abstrak: Nucleopolyhedrovirus (NPV) merupakan virus entomopatogen dari famili Baculoviridae yang ditemukan menginfeksi berbagai jenis serangga dari ordo Lepidoptera, salah satunya adalah Helicoverpa armigera dari famili Noctuidae. Jenis NPV yang spesifik menginfeksi H. armigera disebut HearNPV. H. armigera merupakan hama penting pada berbagai komoditas seperti jagung, tomat, kapas, dan kedelai. Tujuan penelitian adalah mendesain primer spesifik DNA polymerase dalam teknik PCR yang digunakan untuk melengkapi informasi karakter genetik dari gen DNA polymerase pada HearNPV isolat Bogor. Amplifikasi gen HearNPV dilakukan dengan metode PCR dilanjutkan dengan pengurutan DNA menggunakan program BioEdit dan BLAST. Analisis homologi dan filogeni dilakukan dengan MEGA 11 untuk mengetahui hubungan kekerabatan genetik dari isolat NPV dengan isolat dari negara lain yang terdapat pada GenBank. Hasil amplifikasi PCR menunjukkan ukuran fragmen DNA NPV sebesar 367 pb. Berdasarkan hasil analisis sekuens, isolat HearNPV asal Bogor memiliki hubungan dekat dengan isolat NPV yang berasal dari Spanyol dan India. Nilai homologi nukleotida dan asam amino tertinggi secara berturut-turut sebesar 99,15% dan 99%. Berdasarkan hasil analisis filogeni, isolat HearNPV asal Bogor termasuk dalam kelompok yang sama dengan NPV yang menginfeksi genus Helicoverpa., Nucleopolyhedrovirus (NPV) is an entomopathogenic virus from the Baculoviridae family that infects various types of insects from the order Lepidoptera, one of which is Helicoverpa armigera. HearNPV is an NPV that specifically infects H. armigera. H. armigera is an important pest on commodities such as corn, tomatoes, cotton and soybeans. This study was conducted to design DNA polymerase-specific primers using PCR techniques and to complement the genetic information of the DNA polymerase genes in HearNPV Bogor isolate using those pre-designed primers. HearNPV gene amplification were carried out using the PCR method, followed by DNA sequencing using the BioEdit software and the BLAST program. Homology and phylogeny analyses were carried out using the MEGA 11 program to determine the genetic relationship of NPV isolates with isolates from other countries found in GenBank. The PCR amplification results showed that the size of the NPV DNA fragment was 367 bp. Based on the sequence analysis results, HearNPV isolates from Bogor are closely related to NPV isolates from Spain and India. The highest nucleotide and amino acid homology values were 99.15% and 99%, respectively. Based on the results of phylogenetic analysis, HearNPV isolates from Bogor belong to the same group as the NPVs that infect the genus Helicoverpa.
Keyword: Baculovirus, filogeni, hubungan genetik, sekuens nukleotida, virus serangga

Judul: Penggunaan Gen DNA Polimerase untuk Menentukan Hubungan kekerabatan Helicoverpa armigera Nucleopolyhedrovirus (HearNPV) Bogor
Abstrak: Nucleopolyhedrovirus (NPV) merupakan virus patogen serangga yang penting di antara famili Baculoviridae. NPV diketahui mampu menjadi agen hayati untuk mengendalikan serangga hama dari ordo Lepidoptera, misalnya Helicoverpa armigera. NPV memiliki sifat yang spesifik, virulen, dan persisten di lapangan sehingga dapat digunakan petani sebagai insektisida hayati. Helicoverpa armigera merupakan salah satu hama yang menyerang tanaman jagung. H. armigera dapat dikendalikan secara hayati menggunakan HearNPV. Sekuen nukleotida HearNPV di Indonesia masih terbatas. Penelitian ini bertujuan untuk mengetahui hubungan kekerabatan isolat HearNPV Bogor dengan NPV lain yang tercatat di GenBank melalui sekuen nukleotida gen DNA Polimerase parsial. Gen DNA Polimerase merupakan salah satu gen inti dari virus genus baculovirus yang terlibat dalam proses replikasi. Karakteristik homologi dan filogeni digunakan untuk memberikan informasi tentang hubungan HearNPV Bogor (berasal dari pertanaman jagung sekitar kampus IPB Dramaga) dengan NPV yang telah dilaporkan di situs GenBank. Analisis filogeni dilakukan menggunakan pendekatan ‘NeighborJoining’ Bootstrap 1000x dengan program MEGA 11. Hasil analisis homologi nukleotida dan asam amino menunjukkan HearNPV Bogor memiliki kekerabatan yang dekat dengan HearNPV Spanyol (No. aksesi: KJ701033.1) dan Australia (No. aksesi: AIG63247.1). Berdasarkan analisis filogeni, HearNPV Bogor berada dalam kelompok yang sama dengan NPV yang menyerang genus Helicoverpa lain di dunia., Nucleopolyhedrovirus (NPV) is an important insect pathogenic virus in the Baculoviridae family. NPV is known to be a biological agent for controlling insect pests of Lepidoptera, for example, Helicoverpa armigera. NPV has a specific host, virulent, and persistent in the field so it can be used by farmers as a biological insecticide. Helicoverpa armigera is one of the pests that attack corn plants. H. armigera can be controlled biologically using HearNPV. HearNPV nucleotide sequences in Indonesia are still limited. This study aimed to determine the kinship relationship of the HearNPV Bogor isolates with other NPVs recorded in GenBank through nucleotide sequences of the partial DNA Polymerase gene. DNA Polymerase gene is one of the core genes of the baculovirus genus virus involved in the replication process. Homology and phylogeny characteristics were used to provide information about the relationship between HearNPV Bogor and the NPV that had been reported on GenBank. The phylogeny analysis was carried out using the 'Neighbor-Joining' Bootstrap 1000x approach with the MEGA 11 program. The nucleotide and amino acid homology analysis results showed that HearNPV Bogor had a close relationship with the HearNPV of Spain (Accession: KJ701033.1) and Australia (Accession: AIG63247.1). Based on phylogenetic analysis, HearNPV Bogor in the same group as NPVs that attack other Helicoverpa genera worldwide.
Keyword: BLAST, entomopathogen, homology, phylogeny

Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
Keyword: