Bemisia tabaci is one of the most important global agricultural insect pests, being a vector of emerging plant viruses such as begomoviruses and criniviruses that cause serious problems in many countries. Although knowledge of the genetic diversity of B. tabaci populations is important for controlling this pest and understanding viral epidemics, limited information is available on this pest in Brazil. A survey was conducted in different locations of São Paulo and Mato Grosso states, and the phylogenetic relationships of B. tabaci individuals from 43 populations sampled from different hosts were analysed based on partial mitochondrial cytochrome oxidase 1 gene (mtCOI) sequences. According to the recently proposed classification of the B. tabaci complex, which employs the 3.5% mtCOI sequence divergence threshold for species demarcation, most of the specimens collected were found to belong to the Middle East‐Asia Minor 1 species, which includes the invasive populations of the commonly known B biotype, within the Africa/Middle East/Asia Minor high‐level group. Three specimens collected from Solanun gilo and Ipomoea sp. were grouped together and could be classified in the New World species that includes the commonly known A biotype. However, six specimens collected from Euphorbia heterophylla, Xanthium cavanillesii and Glycine maxima could not be classified into any of the 28 previously proposed species, although according to the 11% mtCOI sequence divergence threshold, they belong to the New World high‐level group. These specimens were classified into a new recently proposed species named New World 2 that includes populations from Argentina. Middle East‐Asia Minor 1, New World and New World 2 were differentiated by RFLP analysis of the mtCOI gene using TaqI enzyme. Taq I analysis in silico also differentiates these from Mediterranean species, thus making this method a convenient tool to determine population dynamics, especially critical for monitoring the presence of this exotic pest in Brazil.

AbstractThe whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is one of the most important agricultural pests and virus vectors worldwide. Bemisia tabaci is considered a complex of cryptic species with at least 44 species. Among them, the species Middle East-Asia Minor 1 (MEAM1, formerly B biotype) and Mediterranean (MED, formerly Q biotype) are the most important, and they have attained global status. In Brazil, MEAM1 was first reported in the 1990s and is currently the predominant species in the country, meanwhile, MED was recently reported in the South and Southeast regions and was found to be mainly associated with ornamental plants. Currently, an increasing problem in the management of whitefly infestations in greenhouses associated with bell pepper was observed in São Paulo State, Brazil. The whiteflies were collected and identified based on a microsatellite locus (primer pair BEM23F and BEM23R) and the mitochondrial cytochrome oxidase I gene followed by restriction fragment length polymorphism analysis and sequencing. We observed that MED was the predominant species collected on bell pepper, but it was also found on tomato, cucumber, eggplant, and weeds grown in greenhouses. In open field, we found MED on tomatoes, bell peppers, and eggplants. In addition, MED was identified in Goiás State in association with ornamental plants. The begomovirus Tomato severe rugose virus and the crinivirus Tomato chlorosis virus was detected on bell pepper and tomato, respectively. Only MED specimens were found associated with the virus-infected plants. Moreover, we also investigated the endosymbionts present in the MED whiteflies. The collected populations of B. tabaci MED harbored a diversity of secondary endosymbionts, with Hamiltonella (H) found predominantly in 89 specimens of the 129 tested. These results represent a new concern for Brazilian agriculture, especially for the management of the newly introduced whitefly MED species, which must be implemented to limit the spreading and establishment of this pest in different crops in this country.

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The golden mosaic (begomovirus) and the yellowing (crinivirus) diseases are among the main viral diseases occurring in solanaceous crops in Brazil. A survey of viruses associated with both diseases was conducted on cultivated solanaceous plants from 2013 to 2017 to study their diversity and distribution in the Southeast/Midwest regions of Brazil. Samples from potato, eggplant, sweet pepper and tomato plants were collected in fields of seven Brazilian states (

Pepper yellow mosaic virus (PepYMV) is the most important potyvirus infecting sweet pepper in Brazil. In this study, twenty isolates of PepYMV were obtained from commercial sweet pepper crops. To confirm virus identity, the coat protein gene was completely sequenced for eleven of these isolates, and partially sequenced for the other nine isolates. The amino acid identities obtained were above 93% when compared with the sequence of a characterized PepYMV isolate (AF348610). Extracts of Nicotiana tabacum cv. TNN plants infected with the different isolates were used to inoculate the differential series of Capsicum spp cultivars containing the genes pvr2 1 , pvr2 2 , pvr2 3 , pvr2 4 , and Pvr4. Using the same criteria established for Potato virus Y (PVY), fourteen isolates of PepYMV could be classified as known pathotypes described for PVY, that is: 1.2 (2 isolates), 1.3 (6) and 1.2.3 (6). The remaining six isolates, 1.3 (2) and 1.2.3 (4) could not be classified into the typical pathotypes of PVY because they were also virulent on Serrano Criollo de Morellos-334 (C.M 334) which carries the pvr2 3 and Pvr4 genes. To classify the PepYMV into pathotypes and counter the biological diversity found in this species we propose the utilization of 2 x for the ability to overcome the correspondent allele of the pvr2 locus and 4 for the capacity to break down the Pvr4 gene. Using this criterion we could classify the PepYMV into five

Reaction and colonization of common bean genotypes by INTRODUCTIONBrazil is one of the world's leading common bean producers and consumers, with a harvest of almost three million tons in 2012, in the main producing states of Paraná, Minas Gerais, São Paulo and Goiás (Agrianual 2013). Bacterial diseases are among the yield-limiting factors of the crop in the country, particularly bacterial wilt. This disease is caused by Curtobacterium flaccumfaciens pv. flaccumfaciens (Cff), and was first described by Hedges (1922) in the USA. Currently, the disease has already been detected in several countries (EPPO 2011) and Brazilian states (Valentini et al. 2010). Bacterial wilt colonizes the xylem vessels of the affected plants, leading to disruption and degradation of the primary xylem. Infected plants show symptoms of wilting leaves, which later evolve to withering and death (Dinesen 1978). Yield losses in susceptible cultivars can be close to 50% (Miranda Filho 2006). Bacterial wilt is controlled by preventive measures, e.g., by using healthy seeds, incorporation of crop bean residues into the soil, crop rotation with non-host species, and by using cultivars with some level of resistance (Huang et al. 2009, Valentini et al. 2010.A number of studies identified Cff-resistant common bean genotypes in Brazil. According to Maringoni (2002), high resistance levels were observed in the cultivars IAC Carioca Akytã, IAC Carioca Aruã, and IAC Carioca Pyatã. Souza et al. (2006) Carioca Aruã, IAC Carioca Pyatã, and IAC Carioca Tybatã, whose resistance reactions were found to be as described by Maringoni (2002) and Souza et al. (2006).

Garlic (Allium sativum L.) can be infected by several viruses of the genera Allexivirus, Carlavirus, and Potyvirus (3). Garlic common latent virus (GarCLV) and Shallot latent virus (SLV) are the most important Carlavirus species infecting garlic, but only GarCLV has been described on garlic in Brazil. Seven hundred thirty-one samples of garlic showing mosaic symptoms and chlorotic streaking were collected from the states of São Paulo (São Manuel), Minas Gerais (Santa Juliana and São Gotardo), Goiás (Campo Alegre and Ipameri), and Paraná (Guarapuava and Piraquara) from April 2008 to July 2009 and analyzed by double-antibody sandwich (DAS)-ELISA for the presence of GarCLV and SLV using specific antiserum for SLV and GarCLV according to the manufacturer's protocol (Agdia Inc., Elkhart, IN). Cultivars sampled were Caçador, Chonan, Ito, Jonas, Quitéria, and Tropical. Fifty-five samples (7.5% of 731) tested positive for GarCLV, and none of the samples tested positive for SLV. Total RNA was extracted (2) from 15 samples that represented different states of production and used with primers SLV 7044 (5′-CTTTTGGTTCACTTTAGG-3′) and SLV 8004 (5′-GCACGCAATAGTCTACGG-3′), designed in this study, to detect SLV in a one-step reverse transcription (RT)-PCR assay. Only 3 of the 15 samples, two from São Paulo and one from Paraná State, produced a 960-bp fragment covering the putative coat protein gene (ORF 5) (1) of SLV. The amplicons of the three isolates were sequenced. A nucleotide sequence identity of 91 to 92% was detected in comparison with two strains of SLV (GenBank Accession Nos. AB004567 and DQ520093), indicating the presence of two isolates of SLV in São Manuel (São Paulo State) and one in Piraquara, Paraná State (submitted to GenBank as Accession Nos. GU120176, HQ128602, and GU120175, respectively). To confirm identity of the virus, another pair of primers was constructed and tested (SLV 6737: 5′-YCCSGCCARGAAYTTCCC-3′, and SLV 7060: 5′-TTAGAGCGCTGTWAACC-3′), from which a 340-bp fragment covering a portion of TGB2 (ORF 3) and TGB3 (ORF 4) (1) was amplified using the two isolates from São Paulo (GenBank Accession Nos. HQ123181 and HQ123182, respectively). The amplicon sequences shared 87% identity with that of an SLV isolate (Accession No. AJ292226), which confirmed the presence of SLV. The low titer of SLV in garlic might account for the false negative results by DAS-ELISA. The source of cultivated garlic bulbs in these regions of Brazil is unknown. Garlic cloves have been cultivated in São Manuel for approximately 15 years, indicating that SLV may have been present in Brazil for many years. To our knowledge, this is the first report of SLV in Brazil. References: (1) M. J. Adams et al. Virus Taxonomy: 8th Report of the International Committee on Taxonomy of Viruses. Elsevier Academic Press, 2005. (2) Y. D. Bertheau et al. Methods for the Detection and Quantification of Erwinia carotovora subsp. atroseptica on Potatoes. M. C. N. Perombelon and J. M. van der Wolff, eds. Scottish Crop Research Institute, Dundee, U.K., 1998. (3) T. V. M. Fajardo et al. Fitopatol. Bras. 26:619, 2001.

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