Judul: Identification of Viruses Cause Pineapple Mealybug Wilt Disease on Pineapple Clone 7350 and Clone MD2 in Blitar Regency, East Java
Abstrak: Nanas (Ananas comosus L. Merr) merupakan salah satu komoditas ekspor penting di Indonesia. Namun, produksinya terkendala oleh infeksi patogen, termasuk virus. Baru-baru ini, survei lapangan di area produksi nanas di Kabupaten Blitar menemukan gejala mirip infeksi virus seperti daun kemerahan bercampur dengan klorosis dan ujung daun nekrotik dengan kejadian hingga 50% pada klon 7350. Penyakit ini telah diketahui menginfeksi nanas. Namun sampai saat ini identitas genetik virus penyebab penyakit layu mealybug di Indonesia masih terbatas. Penelitian bertujuan untuk mendeteksi dan mengidentifikasi spesies virus yang berasosiasi dengan penyakit layu nanas di Kabupaten Blitar. Total RNA diekstraksi dan dideteksi dengan One-Step RT-PCR menggunakan primer universal Ampelovirus, primer spesifik dari pineapple mealybug wilt-associated virus (PMWaV) 1 dan 2. Sampel positif kemudian dikonfirmasi dengan analisis runutan nukleotida. PMWaV-1 dan -2 berhasil diamplifikasimenggunakan primer spesifik pada klon 7350 dan tidak ada sampel yang terdeteksi menggunakan primer universal Ampelovirus. Di sisi lain, semua pasang primer tidak mendeteksi virus target pada klon MD2, menunjukkan gejala klorosis mungkin disebabkan oleh patogen lain. Urutan parsial gen HSP70 mengkonfirmasi keberadaan kedua spesies virus. Isolat PMWaV-1 Blitar memiliki kesamaan tertinggi (100%) nukleotida dan asam amino dengan isolat dari Taiwan dan Meksiko. Selain itu, isolat PMWaV-2 Blitar menunjukkan homologi masing-masing 99% dan 100% untuk kesamaan nukleotida dan asam amino, dengan isolat dari Taiwan, Mauritius, Kuba, dan Ghana. Hasil dari penelitian ini memastikan adanya dua spesies virus (PMWaV-1 dan -2) yang menyebabkan penyakit layu mealybug., Pineapple (Ananas comosus L. Merr) is one of the essential export commodities in Indonesia. However, virus infection causes significant yield loss. Current field survey at a pineapple production area in Blitar Regency found virus-like infection symptoms such as leaf reddish intermingle with chlorosis and necrotic leaf tips on clone 7350 and MD2 with incidence 50% and 3%, respectively. To date, there was still few information of viruses infecting pineapple in Indonesia. The aim of this study is to identify the virus species associated with mealybug wilt pineapple disease in Blitar Regency. Total RNA was extracted then detected through one-step RT-PCR method using three primer sets, including a universal primer of Ampelovirus and two specific primer pairs (PMWaV-1 and -2). Positive samples then were confirmed by nucleotide sequencing. The PMWaV-1 and PMWaV-2 were successfully amplified using specific primers on clone 7350 and there were no samples detected using Ampelovirus universal primers. In the other hand, all the primer sets did not detect any virus target on clone MD2, indicating chlorosis symptom might be caused by other pathogens. Partial sequences of the HSP70 gene confirmed the existence of both virus species. The PMWaV-1 Blitar isolates shared the highest similarities (100%) of nucleotide and amino acid with isolates from Taiwan and Mexico, respectively. Moreover, the PMWaV-2 Blitar isolates shared 99% and 100% similarities of nucleotide and amino acid, respectively with isolates form Taiwan, Mauritius, Cuba, and Ghana. The finding of this study confirmed the existence of two viruses (PMWaV-1 and -2) causing pineapple mealybug wilt disease.
Keyword: Ampelovirus, Ananas comosus, HSP70, PMWaV, RT-PCR

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: Penambahan modul pembentukan Word Graph kata kerja pada aplikasi BogorDelftConstruct
Abstrak: Knowledge Graph (KG) is one of natural language processing methods that is able to represent the result of semantic analysis of a text in a graph form. Until now, there are only a few researches using KG to do semantic analysis for texts in Indonesian language. They were mainly focus on analyzing text, constructing rules to analyze text and engineering to understand the text. Some other researches have done semantic analysis from various part-of-speech. Nevertheless, the results of the research have not been implemented yet. To realize a long term goal of doing text abstraction automatically, BogorDelftConstruct has been developed as an early stage prototype. In line with that, this research implemented semantic analysis for one part-of-speech in BogorDelftConstruct.
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