Fernanda Rausch Fernandes

Three distinct begomoviruses associated with soybean in central Brazil.

We report the complete nucleotide sequences of geminiviruses of the genus Begomovirus infecting soybean (Glycine max) in central Brazil. Samples obtained from soybean plants collected at Santo Antonio de Goiás, Goiás State, showing typical symptoms of viral infection, were analyzed. Infection was confirmed by PCR-based amplification of a DNA-A fragment with universal begomovirus primers. Total DNA from infected plants was then subjected to rolling-circle amplification (RCA), and 2.6-kb molecules were cloned into plasmid vectors. Sequencing of the three DNA-A and two DNA-B clones thus obtained confirmed infection by three distinct begomoviruses: bean golden mosaic virus, Sida micrantha mosaic virus and okra mottle virus, the last of which was reported recently to be a novel virus infecting okra plants in Brazil. Begomovirus infection of soybean plants has been reported sporadically in Brazil and has generally not been considered to be of economic relevance.

Further characterization of tomato-infecting begomoviruses in Brazil.

Tomato cultivation in Brazil is threatened by a number of tomato-infecting viruses belonging to the genus Begomovirus of the family Geminiviridae. Here, we report the full DNA-A sequences of three Brazilian begomoviruses: a potentially new tomato-infecting viruses, tomato interveinal chlorosis virus (ToICV), and two previously proposed begomoviruses for which only partial DNA-A sequences are available in the databases: tomato mottle leaf curl virus (TMoLCV) and tomato golden vein virus (TGVV). The complete sequences of the DNA-B components of TMoLCV and TGVV and the DNA-A components of a number of tomato severe rugose virus variants are also presented. Collectively, all of the analyzed sequences were phylogenetically clustered within the two major groups of Brazilian tomato-infecting begomoviruses.

Molecular and biological characterization of a new Brazilian begomovirus, euphorbia yellow mosaic virus (EuYMV), infecting Euphorbia heterophylla plants

To date, no begomovirus has been fully characterized from Euphorbia heterophylla, a widely distributed weed, in Brazil. Here, we show the occurrence of a new begomovirus on E. heterophylla plants showing bright yellow mosaic. The bipartite viral genome was cloned from 10 samples, and all clones are almost identical to each other (95.6-98.8% nucleotide sequence identity). The DNA-A sequences shared a maximum nucleotide sequence identity of 87.3% with euphorbia mosaic Peru virus (EuMPV) and thus were classified as belonging to a novel begomovirus species, tentatively named Euphorbia yellow mosaic virus (EuYMV). The EuYMV DNA-B sequences share a maximum nucleotide sequence identity of 56.2% with a euphorbia mosaic virus (EuMV) isolate from Mexico. Phylogenetic analysis demonstrated that this new virus belongs to a different lineage than EuMV isolates from Central America.

Development of methodologies for virus detection in soybean and wheat seeds

Graphical abstract

Interception of ‘Candidatus Phytoplasma solani’ in Brazil in apple tree propagative material imported from France

Arq. Inst. Biol., v.84, 1-4, e0602016, 2017 ABSTRACT: Apple plants from France introduced in Brazil for research purposes were subjected to a phytosanitary analysis at the Plant Quarantine Laboratory of Embrapa Genetic Resources and Biotechnology (Cenargen). After grafting onto healthy apple rootstock, some plants showed phytoplasmainfection symptoms. Polymerase Chain Reaction (PCR) tests yielded DNA fragments of the expected size for phytoplasmas. DNA sequencing revealed an identity of the 16S rDNA nucleotide sequence of 98-99% with ‘Candidatus Phytoplasma solani’. This phytoplasma species is responsible for losses in European apple orchards and has not been reported in Brazil. According to the Federal Legislation on Plant Protection, the plants were incinerated to avoid the introduction of this exotic pest in Brazil.

Interceptação do Wheat mosaic virus (WMoV) no Brasil em sementes de milho provenientes dos Estados Unidos

The objective of this work was to evaluate the phytosanitary aspect of two accessions of maize ( Zea mays ) seeds from the United States introduced to Brazil, regarding the presence of Wheat mosaic virus (WMoV). Two to three weeks after sowing, symptomatic leaves were tested by Elisa using specific antiserum to WMoV. The reaction was positive, and leaf samples were analyzed by real‑time PCR and amplified PCR products were sequenced. The WMoV isolates had 99 to 100% nucleotide identity with isolates from Australia and the United States. Until now, there is no report of the presence of this virus in Brazil. According to the federal law on plant protection, the plants were burned to avoid the introduction of this exotic pest in the country. The obtained results show WMoV interception in Brazil.

Fundamentos biológicos, ferramentas operacionais e inovação em quarentena vegetal

The demand toward food and nutritional security delimitates models for agricultural intensification, in which yield loss prevention is essential. The globalized agriculture scenario, the increase of trade routes, and the displacement of people and products maximize the potential of nondeliberate pest introductions in undamaged areas, endangering the production systems. Plant quarantine is presented as a measure to control plant product movement, in order to limit the dispersal of agricultural pests. Surveillance advocates the anticipation and recognizes the threat, focusing on the accuracy and efficiency of the diagnosis, on the consolidation of methods of pest risk analysis, and on the evolution of operational tools. Responses to the challenges posed to agriculture security are expected, considering the appropriation of new technologies, enhancement of inspectorate structures, and a strong, innovative capacity. This work approaches the historical aspects related to quarantine actions, legal framework, influence of international trade, analytical tools, innovation perspectives, and infrastructure qualification. The objective of this work is to contextualize the risk importance of introducing new pests, faced with a thriving agriculture and the intensification of commercial interchange. It also analyses the challenges to plant quarantine actions, while it aligns the biological grounding on which the phytosanitary regulation should be sustained, in order to subside the formulation of legal security measures.