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Dahlia is an important ornamental crop in the U.S. The economic value of the crop is often affected by viral diseases. Of several viruses that infect dahlia, dahlia mosaic virus (DMV) is of most concern. However, little or no information is available about its distribution. A survey of dahlias in several states in the U.S. was carried out during 2003 and 2004. Samples from CA, GA, MD, ME, MT, NM, PA, OR, and WA were tested for DMV. To develop a molecular detection assay, the viral genome was cloned and sequenced and based on the sequence information, DMV-specific primers were used in a PCR-based assay. DMV was detected in >90% of the samples tested. Based on the detection of DMV, a wide range of symptoms were found to be associated with DMV infection. A real-time PCR assay was adapted for rapid detection of DMV. Considering its widespread occurrence, steps are needed to limit its further spread. An effective intervention program would include use of virus-free material to minimize its impact. Availability of a rapid and sensitive detection method such as the once described should facilitate not only production of virus-free dahlias but elimination of virus infected material from breeding and propagating stocks. This is the first report of a survey to determine the extent of DMV incidence in dahlias. [ABSTRACT FROM AUTHOR]

Caladium ( Caladium × hortulanum ) is an ornamental plant popular for its variable and colorful foliage. In 2020, plants showing leaf spots and blight, typical of anthracnose, were found in a field trial at the University of Florida's Gulf Coast Research and Education Center in Wimauma, Florida, U.S.A. Leaf samples consistently yielded a Colletotrichum- like species with curved conidia and abundant setae production in the acervuli. The internal transcribed spacer (ITS), partial sequences of the glyceraldehyde-3-phosphate dehydrogenase gene ( gapdh ), actin gene ( act ), chitin synthase 1 gene ( chs-1 ), beta-tubulin gene ( tub2 ), and histone3 gene ( his3 ) were amplified and sequenced. BLASTN searches in the NCBI GenBank database revealed similarities to species of the Colletotrichum truncatum species complex. Phylogenetic analyses using multilocus sequence data supports a distinct species within this complex, with the closest related species being C. curcumae . Based on morphological and phylogenetic analyses, a new species of Colletotrichum , named C. caladii , is reported. Pathogenicity assays and subsequent isolation confirmed that this species was the causal agent of the disease., Competing Interests: The author(s) declare no conflict of interest.

Background: Although potentially curable with early detection and timely treatment, breast cancer (BC) and cervical cancer (CC) remain leading causes of death for Colombian women. Lack of education, complicated administrative processes, and geographic limitations hinder early cancer detection. Today, technological tools permeate the society and could assess user risk, deliver customized information, and provide care coordination. We evaluated the effectiveness of a free mobile application (mApp) to reach women, understand misconceptions, identify users at risk for BC and/or CC, and coordinate screening tests in Cali, Colombia., Methods: The mApp was developed and advertised in four healthcare facility waiting rooms. It used educational, evaluative, and risk factor questions followed by brief explanations to assess the population's knowledge, educate on BC and/or CC, and identify users in need of screening test(s). Women who required screening were navigated and enrolled in the national cancer program., Results: From August 2017 to August 2019, 1,043 women downloaded the mApp. BC misconceptions included beliefs that BC can be prevented (87%), obesity does not increase the risk of BC (49%), and deodorant causes BC (17%). CC misconceptions included that pap smears should not be performed while sexually active (64%), vaginal pain is an early sign of CC (44%), and only women contract human papilloma virus (33%). Overall, 29% (303) were identified as at risk and needed a screening test, with 32% (98) successfully screened., Discussion: mApps can identify women at risk for BC and/or CC, detect barriers to early cancer detection, and help coordinate screening test(s). This technology has widespread applications and may be useful in other underserved communities.

A DNase released from the fungal pathogen of bean, Fusarium solani f. sp. phaseoli (Fsph), was previously shown to signal the activation of total disease resistance and activate pathogenesis-related (PR) genes in pea. Data in the current study which used the pea-endocarp model to research non-host resistance, indicated that DNase released by Verticillium dahliae (Vd), pathogenic on potato also has non-host resistance-inducing capabilities in peas. Other strains of Vd that release DNase are pathogenic on other plant species. DNase catalytic activity was also released from representative genera of other pathogenic fungi. Purified VdDNase induced pisatin and pea gene DRR49 (PR-10 gene) in pea endocarp tissue. VdDNase reduced the in vitro growth of Vd but completely inhibited that of F. solani f. sp. pisi (Fspi) and a Colletotrichum pathogen of potato. VdDNase (2 units) applied to pea endocarp tissue both broke resistance to Fsph and increased resistance to Fspi. Pea DNA damage generated both by the VdDNase enzyme and the intact Vd spores indicated that the host DNA alteration is a component of the non-host resistance response (innate immunity). These data support the previously reported inductive potential of fungal DNase and further implicate fungal DNases as signals in activating non-host resistance responses., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

The genus Caulimovirus consists of several distinct virus species with a double-stranded DNA genome that infect diverse plant species. A comparative analysis of the sequences of known Caulimovirus species revealed two regions that are conserved in all Caulimovirus species with the exception of Strawberry vein banding virus. Degenerate primers based on these two regions were designed and tested in a polymerase chain reaction-based assay for broad spectrum detection of members of this genus. Cauliflower mosaic virus, Figwort mosaic virus and three distinct caulimoviruses associated with dahlia (Dahlia variabilis) were used to show the utility of this test in detecting diverse caulimoviruses. The primer pair gave an amplicon of expected size (840bp). Amplicons from each virus were cloned and sequenced to verify their identity. The primer pair and the PCR assay provide approach for the broad spectrum detection of several members of the genus Caulimovirus.

Viruses in certain genera in family Caulimoviridae were shown to integrate their genomic sequences into their host genomes and exist as endogenous pararetroviral sequences (EPRV). However, members of the genus Caulimovirus remained to be the exception and are known to exist only as episomal elements in the infected cell. We present evidence that the DNA genome of a new and distinct Caulimovirus species, associated with dahlia mosaic, is integrated into its host genome, dahlia (Dahlia variabilis). Using cloned viral genes as probes, Southern blot hybridization of total plant DNA from dahlia seedlings showed the presence of viral DNA in the host DNA. Fluorescent in situ hybridization using labeled DNA probes from the D10 genome localized the viral sequences in dahlia chromosomes. The natural integration of a Caulimovirus genome into its host and its existence as an EPRV suggests the co-evolution of this plant-virus pathosystem.