Judul: Identifikasi Spesies Polerovirus pada Tanaman Wortel melalui Analisis Sekuen Nukleotida Gen Coat Protein
Abstrak: During survey on central production of carrot in West Java, some plants were found exhibiting virus-like induced symptoms. The diseased plants showed reddening and yellowing of leaves, but the plants were unlikely to be stunting. The symptom was resemble to the disease reported in other countries as „motley dwarf‟, in which the reddening, yellowing, and stunting is accentuated. The disease was reported to be caused by mixed infection of two different viruses that were Carrot red leaf virus (CtRLV), member of genus Polerovirus and Carrot mottle mimic virus (CMoMV), member of genus Umbravirus. To know the causal agent of the disease present in Indonesia, total RNA extraced from the symptom exhibiting carrot plants obtained from field in Cipanas, Cianjur, West Java was subjected to reverse transcription-polymerase chain reaction (RT-PCR) using primer pair specific to CtRLV. Unfortunately, the virus was failed to be detected and therefore, further identification was focused on other virus. Using primer pair of CP-F (5‟-AATTAAGGATCCAATACGGGAGGGGTTAGGAGAAAT-3‟) and CP-R (5‟-AATTAACTGCAGTTTCGGGTTGTGCAATTGCACAGTA-3‟), that were specific to Polerovirus. RT-PCR was successfully amplified a DNA band of about 650 bp, the size which accordance with the designed primers. The RT-PCR product was then sequenced and the 630 nucleotides were succesfully read. The BLAST analysis of the nucleotide sequence revealed that the virus associated with red leaf disease on carrot in West Java was associated with Pepper vein yellow virus (PeVYV). PeVYV was a virus found previously infected chilli pepper in Bali. This is the first report concerning PeVYV infected carrot in Indonesia.
Keyword: reverse transcriptionpolymerase chain reaction, red leaf disease, Pepper vein yellow virus

Judul: Identifikasi Spesies Polerovirus Penyebab Penyakit Klorosis pada Tanaman Cabai Melalui Sekuen Nukleotida
Abstrak: During survey on chilli pepper in Kertha Vilage, Payangan Distric, Gianyar Regency, Bali Province, there were found that many chilli pepper plants showing virus like induced symptom of chlorosis. Leaves of diseased plant exhibited yellowing appearance with interveinal chlorosis but the vein still with normal green color. This disease symptom is different from that of induced by viruses had been reported present in Indonesia. The disease was similar with that of induced by Polerovirus reported from other countries. Thus, the attempt of identification was focused on Polerovirus by reverse transcription-polymerase chain reaction (RT-PCR) and nucleotida sequence. By using primer pair specific to Polerovirus that were CP-F (5’-AATTAAGGATCCAATACGGGAGGGGTT AGGAGAAAT-3’) and CP-R (5’-AATTAACTGCAGTTTCGGGTTGTGCAAT TGCACAGTA-3’). RT-PCR applications were successfully amplified a DNA band of about 650 bp from the diseased sample plants, but not from the asymptomatic one. The RT-PCR products were then directly sequenced. Using BLAST program, the nucleotide sequence of the virus isolate has a high homology (more than 90%) with those of Pepper vein yellows virus (PeVYV) from other countries. Thus, the virus associated with chlorosis disease on chilli pepper in Bali was identified as PeVYV. Phylogenetic tree analysis revealed that PeVYV from Bali has closed relationship with the virus isolates from Japan, Taiwan, Thailand, the Philippine, India and Mali.
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Judul: Karakteristik lompatan hidrolik terhadap pelimpah terjunan pada saluran segi empat
Abstrak: Aliran dengan kecepatan tinggi dalam kondisi superkritis yang melintasi bangunan pelimpah, sebelum bergerak lebih jauh ke arah hilir saluran dimana bilangan Froude (F) lebih besar dari satu harus diubah menjadi aliran subkritis dimana bilangan Froudenya lebih kecil dari satu. Aliran yang meninggalkan kaki pelimpah merupakan aliran yang memiliki kandungan energi yang amat berarti sehingga dapat menimbulkan pengikisan yang besar. Pengubahan bilangan Froude dari kondisi superkritis ke subkritis dimaksudkan agar terjadi perubahan kandungan energi, sehingga aliran menjadi non erosive. Agar daya erosive aliran dapat berkurang, maka biasanya pada bagian hilir dari bangunan pelimpah dibuatkan suatu bangunan peredam energi. Erosi yang terjadi di hilir bangunan pelimpah dapat disebabkan dari keberadaan bangunan pelimpah itu sendiri, maupun bangunan peredam energi yang kurang tepat. Hal ini terutama menyangkut beberapa kejadian lompatan hidrolik yang timbul pada bangunan peredam energi tersebut.. Suatu metode yang efektif untuk menjamin bahwa lompatan hidrolik selalu terjadi pada daerah yang dilindungi, adalah dengan menggunakan bangunan peredam energi yang terdiri dari beberapa tipe dengan..dst
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