Judul: Deteksi Virus yang Menginfeksi Kentang (Solanum tuberosum L.) di Jawa Barat
Abstrak: Symptoms of viral infection were found in the center of potato cultivations in West Java (Rancabali, Pengalengan, and Bayongbong). However the viruses associated with these symptoms had been unknown yet. The conducted research aims to detect and identify the viruses molecularly. Fifty leaf samples were randomly collected from symptomatic potato plants of 50 samples at each location. Paramaters measured were symptoms, disease incidence, and viral DNA sequences which were predominantly found. Disease incidence was determined by serological tests using PVY, PVX, PVS, and CMV antiserum. While nucleic acid was amplified by RT-PCR and DNA sequencing. The result showed that the symptoms were found vary in potato leaves, such as mosaic, vein clearing, vein banding, rugose, and leaf malformation. Disease incidence of PVY, PVX, PVS, and CMV in Rancabali were 28%, 0%, 0%, and 28%, in Pengalengan were 80%, 24%, 2%, and 82%, and in Bayongbong were 82%, 0%, 6%, and 74%, respectively. RT-PCR using specific DNA primers successfully amplify PVY and CMV coat protein gene from Bayongbong each approximately size 801 bp and 657 bp. The homology of nucleotide and amino acid of PVY from Bayongbong against PVY isolates from the other countries ranged from 89.5-99.7% and 92.0-100%. The highest homology was closely to PVYNTN from China and Japan. Whereas the homology of nucleotide and amino acid of CMV from Bayongbong against CMV isolates from the other countries ranged from 87.6-96.9% and 86.9-93.7%. The highest homology was closely to CMV strain Soybean stunt (SS) from Bogor (Indonesia). Both of viruses strain (PVYNTN and CMVSS) and PVS were the first reported in potato crops in Indonesia.
Keyword: PVY., potato, CMV

Judul: Deteksi Virus Pada Pertanaman Mentimun (Cucumis Sativus L.) Di Tiga Kabupaten Bogor, Karawang, Dan Subang, Jawa Barat
Abstrak: Penyakit virus banyak ditemukan pada pertanaman mentimun di Jawa Barat. Namun sulit membedakan spesies virus penyebab penyakit berdasarkan pengamatan gejala. Penelitian ini bertujuan untuk memperbaharui informasi data virus yang menginfeksi tanaman mentimun di Kabupaten Bogor, Karawang, dan Subang, provinsi Jawa Barat. Sampel daun mentimun diambil dari tanaman bergejala sebanyak 50 sampel tiap lokasi. Insidensi penyakit virus ditentukan secara serologi dengan metode dot blot immunobinding assay (DIBA) menggunakan antiserum Cucurbit aphid yellow borne virus (CABYV), Cucumber green mottle mosaic virus (CGMMV), Cucumber mosaic virus (CMV), Papaya ringspot virus (PRSV), Squash mosaic virus (SqMV), Watermelon mosaic virus (WMV), dan Zucchini yellow mosaic virus (ZYMV). Deteksi asam nukleat dengan reverse transcription polymerase chain reaction (RT-PCR/PCR) dilakukan terhadap virus baru yang dominan ditemukan dan yang tidak terdeteksi serologi. Gejala yang ditemukan pada daun mentimun berupa mosaik, klorosis, keriting, dan penebalan tulang daun. Hasil deteksi menunjukkan insidensi penyakit oleh CABYV, CGMMV, CMV, PRSV, SqMV, WMV, dan ZYMV di Bogor berturut-turut adalah 100%, 86%, 98%, 0%, 8%, 32%, dan 6%, di Karawang 100%, 98%, 100%, 14%, 72%, 68%, dan 64%, dan di Subang 100%, 88%, 86%, 2%, 8%, 60%, dan 46%. CABYV, CGMMV, dan CMV merupakan virus yang dominan terdeteksi di tiga kabupaten dan PRSV hanya terdeteksi pada sampel asal Karawang dan Subang. RT-PCR menggunakan primer spesifik PRSV, primer universal Polerovirus dan Begomovirus berhasil mengamplifikasi gen protein selubung PRSV asal Karawang berukuran ~ 470 pb dan Polerovirus asal Subang berukuran ~ 450 pb, dan Begomovirus berukuran ~ 900 pb. WMV dan CGMMV perlu deteksi lebih lanjut menggunakan primer spesifik untuk konfirmasi hasil deteksi serologi. Polerovirus dan CGMMV merupakan virus yang baru ditemukan pada mentimun di Jawa Barat.
Keyword: Begomovirus, CGMMV, mentimun, Polerovirus, PRSV

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.
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