ABSTRAKTanaman mentimun dengan gejala daun menguning mulai banyak ditemukan pada sejumlah pertanaman mentimun di Desa Apuan dan Desa Bangli, Provinsi Bali. Penyakit ini diduga berasosiasi dengan Begomovirus karena gejalanya mirip dengan infeksi Begomovirus yang dilaporkan terjadi pada tanaman mentimun di Jawa. Selain itu, kutukebul (Bemisa tabaci) ditemukan di lapangan. Penelitian ini bertujuan mengidentifikasi penyebab penyakit daun kuning pada tanaman mentimun. Deteksi dan identifikasi virus dilakukan dengan teknik polymerase chain reaction menggunakan pasangan primer universal Begomovirus, SPG1/SPG2. Pita DNA berukuran 912 pb berhasil diamplifikasi dari sampel tanaman. Analisis hasil sikuensing nukleotida menunjukkan bahwa Begomovirus yang menginfeksi tanaman mentimun di Bali mempunyai nilai kemiripan tertinggi (91%) dengan Squash leaf curl China virus (SLCCNV) isolat Malaysia. Penelitian ini merupakan laporan pertama infeksi SLCCNV di Bali. ABSTRACTLeaf yellowing symptoms was commonly found in cucumber plants in Bali provinces, i.e. in Apuan and Bangli villages recently. Begomovirus infection is suspected as the causal agent, due to similar symptoms previously reported from cucumber plants in Java. In addition, Bemisia tabaci was observed in the field. The objective of this research was to identify the causal agent of leaf yellowing disease of cucumber in Bali. Virus detection and identification was conducted by polymerase chain reaction method using universal primers for Begomovirus, i.e. SPG1/SPG2. DNA fragment of 912 bp in size was successfully amplified from leaf samples. Analysis of nucleotide sequencing indicated that Begomovirus infecting cucumber plants in Bali has the highest homology (91%) with Squash leaf curl China virus (SLCCNV) isolate from Malaysia. This is the first report of SLCCNV infection in Bali.

Bunchy top symptoms on banana has been reported in Bali Island since early 2011. Symptoms variation were observed in the field similar to infection of Banana bunchy top virus (BBTV). The identity of the BBTV in Bali on the basis of DNA-S nucleotide sequence has not been studied, therefore research was conducted to identify the species of BBTV infecting local banana in Bali based on sequence analysis. Research activities were initiated by collecting field samples from several local banana growing areas in Bali Island. Incidence of bunchy top disease in all locations reached 8% to 44% with disease severity ranged from 2.6% to 30%. Identification of BBTV from field samples were done by polymerase chain reaction using specific primers for BBTV (CPF/CPR) followed by sequence analysis of amplified DNA target. Specific BBTV DNA fragment was successfully amplified from 10 field samples; sequence analysis of DNA fragments showed their highest homology with BBTV. In addition the phylogenetic analysis confirmed the close relationship of  BBTV  isolates from Bali with various BBTV isolates from Indonesia and other isolates from the Asian group in GeneBank.

Tujuan: Dengan mengadopsi sistem pertanian yang selaras alam melalui pendekatan sistem pertanian organik diharapkan menghasilkan komoditas yang sehat dan aman untuk dikonsumsi dan memiliki nilai jual yang lebih tinggi sehingga ke dua misi tersebut dalam jangka panjang dapat dicapai. Metode Penelitian: Penelitian mengenai identifikasi potensi dan pengembangan sistem pertanian organik menuju Bali pulau organik telah dilakukan diseluruh wilayah kabupaten dan Kota di Provinsi Bali sejak bulan Mei – Desember 2019. Penelitian dilakukan melalui survei lapang dan hasilnya disepakati melalui FGD bersama para stakeholder. Temuan: Pengembangan sistem pertanian organik potensial dilakukan hampir seluruh kabupaten di Bali kecuali di Kabupaten Klungkung dan Kota Denpasar. Implikasi: Inovasi yang dihasilkan dari penelitian ini adalah sistem database pertanian organik Provinsi Bali yang online, terintegrasi, kompak, ringan, dan mudah dioperasikan.

The development of strawberry farming in Bali experiencing some obstacles that cause a decline in production, such as wilting disease. The disease was reported caused by the fungi base on morphological recognition.  There are two fungi were recognized caused the strawberry wilt disease in Bali, they are from genus Verticillium and Fusarium. More specific information about causal agent of wilt disease in strawberry especially in Bali is needed. The one accurate identification is done through the molecular approach by analyzing DNA that encode the ribosomal DNA (rDNA). The 18S rDNA, including the internal areas of transcribed spacers (ITS), ITS1 and ITS4 have been widely used in phylogenetic studies. The amplification results of this area produce bands in different sizes that can be used to identify fungal species. Based on that the identification of strawberry wilt disease using molecular analysis was conducted. The 542 bp of Internal Transcribed Spacer (ITS) DNA was successfully amplified using PCR with pairing primers ITS 1 (5-TCCGTAGGTGAACCTGCGG-3’), and ITS 4 (5’-TCCTCCGCTTATTGATATGC-3’). The sequences of three isolates were successfully obtained through sequencing. Homology levels were tested between sequences and showed that Candi Kuning sequence and Gobleg sequence had 95% similarity with sequence of Fusarium oxysporum NRRL 13307 (U34571) from America. While Pancasari sequence have 94% similarity with sequence of Fusarium oxysporum NRRL 13307 (U34571) from America. Candi Kuning, Gobleg, and Pancasari sequences had the same 86% with sequence of Fusarium oxysporum isolate C34-294 Brazil (KJ439088) and had 89% similarity with sequence Fusarium oxysporum f.sp. fragariae China (KT833080). Homology levels were tested between sequences and showed that Candi Kuning sequence and Gobleg sequence had 95% similarity with sequence of Fusarium oxysporum NRRL 13307 (U34571) from America. While Pancasari sequence have 94% similarity with sequence of Fusarium oxysporum NRRL 13307 (U34571) from America. Candi Kuning, Gobleg, and Pancasari sequences had the same 86% with sequence of Fusarium oxysporum isolate C34-294 Brazil (KJ439088) and had 89% similarity with sequence Fusarium oxysporum f.sp. fragariae China (KT833080). Based on phylogeny analysis of Pancasari, Gobleg and Candi Kuning isolates were obtained in one group with Fusarium oxysporum identified in America and Brazil, and also in one group with Fusarium oxysporum f. sp. fragariae that identified in China.

ABSTRAKPenyakit layu stewart merupakan penyakit serius pada tanaman jagung manis (Zea mays). Gejala khas penyakit ini ialah garis berwarna hijau pucat sampai kekuningan yang sejajar dengan tulang daun. Gejala seperti ini ditemukan pada daun jagung manis di daerah Denpasar, Tabanan, Gianyar dan Karangasem pada tahun 2015. Deteksi patogen dengan metode polymerase chain reaction dilakukan menggunakan DNA total yang diisolasi dari daun tanaman bergejala dan pasangan primer CPSL1/ CPSR2c. Amplikon dengan ukuran ~1100 pb berhasil diperoleh dari sampel asal Denpasar. Analisis sikuen nukleotida memastikan bahwa gejala penyakit layu stewart tersebut disebabkan oleh bakteri Pantoea stewartii subsp. stewartii. Hasil analisis sikuen menunjukkan bahwa P. stewartii subsp. stewartii isolat Bali memiliki tingkat homologi yang tinggi (98.97-99.08%) dan berada dalam satu clade dengan isolat asal Kanada, Amerika Serikat, dan Jepang. Ini merupakan laporan pertama mengenai P. stewartii subsp. stewartii yang menginfeksi tanaman jagung di Provinsi Bali.Kata kunci: analisis sikuen, nukleotida, Pantoea, Zea mays ABSTRACT Stewart's wilt is a serious disease of sweet corn (Zea mays). The typical symptoms of the disease are pale-green to yellow linear streaks parallel to the veins. The symptoms were observed on sweet corn in Denpasar, Tabanan, Gianyar, and Karangasem areas during a survey in 2015. Pathogen detection based on a polymerase chain reaction was carried out using total DNA obtained from symptomatic leaf samples and the pairs of primers, CPSL1/CPSR2c. The expected sized (~1100 bp) amplicon was detected in samples from Denpasar. Sequence analysis confirmed that Stewart's wilt disease symptoms are caused by Pantoea stewartii subsp. stewartii. Nucleotide sequence and phylogenetic analysis showed that P. stewartii subsp. stewartii from Bali has high homology (98.97-99.08 %) and placed in the same clade with isolates from Canada, USA and Japan. This is the first report of P. stewarti subsp. stewartii on corn in Bali.

Squash mosaic virus (SqMV) has been reported to infect cucumber plants in Java and cause a decrease in fruit quality and quantity. Until now, there is no information regarding Sqmv infection in Cucurbitaceae in Bali. In a preliminary research conducted during 2020, we found mosaic symptoms in Gianyar, Bali. SqMV was inferred to be the possible cause of the virus-disease-like symptoms. The study aimed to determine the precence of SqMV in Gianyar, Bali and to obtain information related to its molecular character. This research method includes surveys, field observations, virus identification by RT-PCR, and DNA analysis. Severe disease incidence caused by SqMV was observed on cucumber cultivation in Gianyar that was in the range of 5.81–66.87%. PCR using specific primer for coat protein (CP) gene of SqMV was successfully amplified the DNA fragments of ± 582 bp on samples from Payangan, Tegallalang, Ubud, Sukawati, Blahbatuh, and Gianyar districts, except for samples from Tampaksiring. This indicates that the presence of SqMV is widespread in Java and Gianyar.The SqMV isolate from Bali had the highest nucleotide homology at 91.9–93.4% and amino acids 94.0–94.5 and was closely related to the Brazil isolate (KT923125) and had lower isolate homology than other countries (China, Trinidad, Spain, Japan, Arizona, Cekoslowakia, and Australia). It proved that those mosaic symptoms on cucumber is associated with SqMV infection. SqMV is classified as a quarantine organism of category A2, so it is necessary to prevent its spread to other areas.

Sycanus aurantiacus Ishikawa & Okajima, found in Bali, was first described in 2007 as a new harpactorine species based on morphological and biological characteristics; however, its genome has not yet been sequenced. In this study, we examine the mitochondrial cytochrome oxidase subunit I (MtCOI) nucleotide sequence of S. aurantiacus in order to determine whether it represents a new harpactorine species. A sample from Pancasari, Bali, Indonesia was collected at the same location S. aurantiacus was first discovered in 2007. The selected mtCOI gene (650 bp) was successfully amplified using mtCOI primer pairs LCO1490 and HCO2198, and the resulting MtCOI sequence of the S. aurantiacus sample was compared with those from other hapactorine species recorded in GenBank. This comparison revealed low genetic similarity between S. aurantiacus and most other harpactorine species worldwide, except for the Genus Sycanus (JQ888697) from USA whose mtCOI shares approximately 91% similarity with the Pancasari sample. Phylogenetic analysis indicated a close genetic relationship between Sycanus from Bali and the Genus Sycanus (JQ888697) from the USA. The mtCOI sequence of S. aurantiacus had not been recorded previously, and our comparison with existing Sycanus sequences provides support to the understanding that S. aurantiacus is indeed its own species.

Bactrocera carambolae, commonly known as the fruit fly, has been reported as a prominent pest for fruits and vegetables around the world. It has been recorded to infect hosts from a wide range of families and was shown to spread worldwide including Indonesia. The identification of species is needed such that clear information on distribution of the species can be obtained. The combination of analysis through morphology and molecular approaches provide an accurate method of identification. The identification of DNA-based barcode for fruit flies using mitochondrial cytochrome oxidase I gene (mtCOI) was conducted. The result of DNA extraction was amplified using PCR with general primers mtCOI Fruit Fly MT-CO1-F as forward primer and HCO as the reverse primer. A 690bp amplicon of the fruit flies mtCOI gene was obtained. Bactrocera carambolae is the species identified from 9 regencies in Bali Island based on morphology diagnosis and sequence analysis of fruit flies.