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A Hawaiian isolate of Cymbidium mosaic virus (CyMV-H)was purified from Dendrobium orchid, and a cDNA library was constructed. Clones containing the coat protein (CP) gene and movement protein (MP) gene were identified by colony hybridization and polymerase chain reaction (PCR). The Hawaiian isolate of Odontoglossum ringspot virus (ORSV-H) was purified from Cattleya orchid. The CyMV CP gene was PCR amplified from a cDNA clone. The ORSV CP and 54 kDa putative replicase genes and CyMV-MP gene were cloned by RT-PCR. Sequences of these genes of CyMV-H and ORSV-H were compared with those of CyMV and ORSV from Singapore, Japan, Korea, and Germany. The high degree of sequence identity (91_99%) at the nucleotide level for all gene sequences analysed, shows that CyMV and ORSV from different countries are closely related. Sequence comparison results show that CyMV strains can be divided into two groups based on differences in amino acid sequences of the coat protein gene: CyMV-H closely resembles CyMV-SI while CyMV-S2 resembles CyMV-K. A sensitive, rapid, and reliable immunocapture PCR (IC- PCR) assay was developed to detect both viruses. CyMV was detected from dilutions equivalent to 100 ng of orchid material and ORSV was detected from dilutions equivalent to 10 μg of orchid material. IC-PCR was compared with direct binding PCR (DB-PCR) and ELISA for their sensitivities. [ABSTRACT FROM AUTHOR]

Monoclonal antibodies (MAbs) were produced to the pineapple closterovirus (PCV) in Hawaii. These antibodies were shown to be specific for PCV by decoration of the virus particles in immunosorbent electron microscopy (ISEM) and indirect enzyme-linked immunosorbent assay (ELISA). Several methods of ELISA were compared. An indirect DAS ELISA using a polyclonal antibody to trap virus particles followed by reaction with monoclonal antibody was shown to be the method of choice for detecting PCV in pineapple plants. Pineapple root tissue was found to be most suitable for detecting PCV in crude samples by indirect ELISA. PCV was delected in symptomatic and asytnplotnatic pineapple plants collected from Oahu and Maui. and pineapple collections in the USDA/ARS National Clonal Germplasm Repository, but was not detected front pineapple plants grown from seed. At least two serotypes of PCV were detected. In addition. PCV was detected from mealybugs collected from wilted pineapple plants, but not front mealybugs of the same species collected front a colony reared on squash. The role of PCV in mealybug wilt of pineapple is being investigated. [ABSTRACT FROM AUTHOR]

Flowering ginger ( Alpinia purpurata ) is economically and culturally important in Hawaii. In the past decade, a slow decline syndrome has impacted the production of this crop in the state. RNA sequencing analyses and virus indexing surveys were done on samples collected from four of the Hawaiian Islands. Viral sequences corresponding to six viruses were recovered from transcriptomic data from samples with virus-like symptoms. Canna yellow mottle virus (CaYMV, genus Badnavirus ) and two novel viruses, Alpinia vein clearing virus (ApVCV, genus Ampelovirus ) and Alpinia vein streaking virus (ApVSV, genus Betanucleorhabdovirus ), were found at a moderate incidence in diseased plants. Conversely, three other viruses, including the two potyviruses, banana bract mosaic virus and bean common mosaic virus, and a badnavirus, banana streak GF virus, were also found but at a low incidence. Virus detection in potential insect vectors and transmission assays identified the mealybug Planococcus citri as a vector of CaYMV and ApVCV, whereas the aphid Pentalonia caladii was identified as a vector of the novel ApVSV. Both P. citri and P. caladii are common pests of flowering ginger in Hawaii. Transmission of ApVSV was achieved using P. caladii colonies either established in the laboratory or naturally feeding on infected plants, although no transmission was obtained using viruliferous aphids originally reared on taro ( Colocasia esculenta ). Our study provides insights into the potential association between viral infections and the observed decline symptoms of flowering ginger in Hawaii. However, more definitive studies are needed to link single or mixed viral infections with decline symptoms., Competing Interests: The author(s) declare no conflict of interest.

Malabar spinach plants ( Basella alba , Basellaceae) with leaves exhibiting symptoms of mosaic, rugosity, and malformation were found in a community garden on Oahu, HI in 2018. Preliminary studies using enzyme-linked immunosorbent assay and reverse-transcription (RT)-PCR identified Basella rugose mosaic virus (BaRMV) in symptomatic plants. However, nucleotide sequence analysis of RT-PCR amplicons indicated that additional potyviruses were also present in the symptomatic Malabar spinach. High-throughput sequencing (HTS) analysis was conducted on ribosomal RNA-depleted composite RNA samples of potyvirus-positive plants from three locations. Assembled contigs shared sequences similar to BaRMV, chilli veinal mottle virus (ChiVMV), Alternanthera mosaic virus (AltMV), Basella alba endornavirus (BaEV), broad bean wilt virus 2 (BBWV2), and Iresine viroid 1. Virus- and viroid-specific primers were designed based on HTS sequencing results and used in RT-PCR and Sanger sequencing to confirm the presence of these viruses and the viroid. We tested 63 additional samples from six community gardens for a survey of viruses in Malabar spinach and found that 21 of them were positive for BaRMV, 57 for ChiVMV, 21 for AltMV, 19 for BaEV, and 14 for BBWV2. This is the first characterization of the virome from B. alba .

High-throughput sequencing was used to analyze Hibiscus rosa-sinensis (family Malvaceae) plants with virus-like symptoms in Hawaii. Bioinformatic and phylogenetic analysis revealed the presence of two tobamoviruses, hibiscus latent Fort Pierce virus (HLFPV) and a new tobamovirus with the proposed name "hibiscus latent Hawaii virus" (HLHV). This is the first report of the complete sequence, genome organization, and phylogenetic characterization of a tobamovirus infecting hibiscus in Hawaii. RT-PCR with virus-specific primers and Sanger sequencing further confirmed the presence of these viruses. Inoculation experiments showed that HLFPV could be mechanically transmitted to Nicotiana benthamiana and N. tabacum, while HLHV could only be mechanically transmitted to N. benthamiana., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Hibiscus ( Hibiscus spp., family Malvaceae) leaves exhibiting symptoms of mosaic, ringspot, and chlorotic spots were collected in 2020 on Oahu, HI. High-throughput sequencing analysis was conducted on ribosomal RNA-depleted composite RNA samples extracted from symptomatic leaves. About 77 million paired-end reads and 161,970 contigs were generated after quality control, trimming, and de novo assembly. Contig annotation with BLASTX/BLASTN searches revealed a sequence (contig 1) resembling the RNA virus, hibiscus chlorotic ringspot virus (genus Betacarmovirus ), and one (contig 2) resembling the DNA virus, peanut chlorotic streak virus (genus Soymovirus ). Further bioinformatic analyses of the complete viral genome sequences indicated that these viruses, with proposed names of hibiscus betacarmovirus and hibiscus soymovirus, putatively represent new species in the genera Betacarmovirus and Soymovirus , respectively. RT-PCR using specific primers, designed based on the retrieved contigs, coupled with Sanger sequencing, further confirmed the presence of these viruses. An additional 54 hibiscus leaf samples from other locations on Oahu were examined to determine the incidence and distribution of these viruses.

Pyraclostrobin has been widely and long-termly applicated to agricultural fields. The removal of pyraclostrobin from ecological environment has received wide attention. In this study, using sequential enrichments with pyraclostrobin as a sole carbon source, two microbial communities (HI2 and HI6) capable of catabolizing pyraclostrobin were obtained from Hawaiian soils. The microfloras analysis indicated that only Proteobacteria and Bacteroides could survive in HI2-soil after acclimatization, whereas the number of Proteobacteria in HI6-soil accounted for more than 99%. The percentages of Pseudomonas in the HI2 and HI6 microfloras were 69.3% and 59.3%, respectively. More than 99% of pyraclostrobin (C 0  = 100 mg L -1 ) was degraded by the HI2 and HI6 microorganisms within five days. A unique metabolite was identified by high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS/MS). A metabolic pathway involving carbamate hydrolysis was proposed. The tertiary amine group of pyraclostrobin was hydrolyzed to primary amine group with the decarboxylation, which facilitated pyraclostrobin detoxification because carboxylester was an important functional group. The metabolic mechanism suggested that Pseudomonas expressing carboxylesterase might be able to degrade carbamate chemicals. Therefore, Pseudomonas might be an ideal candidate for expression and cloning of carbamate-degrading gene in genomics studies. The current study would have important implications in detoxification and bioremediation of carbamates through the CN bond cleavage of methyl carbamate., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Taro (Colocasia esculenta) is an important food crop, and taro leaf blight caused by Phytophthora colocasiae can significantly affect production. Our objectives were to develop single nucleotide polymorphism (SNP) markers for P. colocasiae and characterize populations in Hawaii (HI), Vietnam (VN) and Hainan Island, China (HIC). In total, 379 isolates were analyzed for mating type and multilocus SNP profiles including 214 from HI, 97 from VN and 68 from HIC. A total of 1152 single nucleotide variant (SNV) sites were identified via restriction site-associated DNA (RAD) sequencing of two field isolates. Genotyping with 27 SNPs revealed 41 multilocus SNP genotypes grouped into seven clonal lineages containing 2-232 members. Three clonal lineages were shared among countries. In addition, five SNP markers had a low incidence of loss of heterozygosity (LOH) during asexual laboratory growth. For HI and VN, >95% of isolates were the A2 mating type. On HIC, isolates within single clonal lineages had A1, A2 and A0 (neuter) isolates. The implications for the wide dispersal of clonal lineages are discussed., (© 2014 by The Mycological Society of America.)

Common green ti plants (Cordyline fruticosa L.) in Hawaii can be infected by four recently characterized closteroviruses that are tentative members of the proposed genus Velarivirus. In this study, a reverse-transcription polymerase chain reaction (RT-PCR) assay developed to detect and distinguish Cordyline virus 1 (CoV-1), CoV-2, CoV-3, and CoV-4 was used to determine: (i) the distribution of these viruses in Hawaii; and (ii) if they are involved in the etiology of ti ringspot disease. One hundred and thirty-seven common green ti plants with and without ti ringspot symptoms were sampled from 43 sites on five of the Hawaiian Islands and underwent the RT-PCR assay. Eleven ornamental ti varieties were also sampled and assayed. Based on this survey, it appears none of the CoVs are involved in the etiology of ti ringspot. The observation of a non-uniform geographic distribution of the CoVs in common green ti, combined with the presence of CoVs in seed-derived ornamental varieties, suggests active vector transmission. Eight herbarium specimens collected between 1903 and 2003 from plants on the island of Oahu also underwent the RT-PCR assay. Amplifiable RNA was isolated from accessions collected in 1985 or later, however only the 2003 accession was found to harbor CoVs.