The Bemisia tabaci is a polyphagous insect and a successful vector of plant viruses. B. tabaci is a species complex and in Brazil native species from the New World (NW) group, as well as the invasive species, Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) were reported. For better understanding the distribution of the different species four years after the Mediterranean species invasion in Brazil, whiteflies were collected from 237 locations throughout the country between the years of 2013 and 2017, species were identified and the facultative endosymbionts detected. The survey revealed that MEAM1 was the prevalent species found on major crops across Brazil. It is the only species present in North, Northwestern and Central Brazil and was associated with virus-infected plants. MED was found in five States from Southeast to South regions, infesting mainly ornamental plants and was not associated with virus-infected plants. The prevalent endosymbionts identified in MEAM1 were Hamiltonella and Rickettsia; and the mtCOI analysis revealed low genetic diversity for MEAM1. In contrast, several different endosymbionts were identified in MED including Hamiltonella, Rickettsia, Wolbachia and Arsenophonus; and two distinct genetic groups were found based on the mtCOI analysis. Monitoring the distribution of the whiteflies species in Brazil is essential for proper management of this pest.

The fungus Rhizoctonia oryzae-sativae is an important pathogen that causes the aggregated sheath spot disease on rice. In this study, we investigated the genetic structure of rice-adapted populations of R. oryzae-sativae sampled from traditional rice-cropping areas from the Paraíba Valley, São Paulo, Brazil, and from Meta, in the Colombian Llanos, in South America. We used five microsatellite loci to measure population differentiation and infer the pathogen's reproductive system. Gene flow was detected among the three populations of R. oryzae-sativae from lowland rice in Brazil and Colombia. In contrast, a lack of gene flow was observed between the lowland and the upland rice populations of the pathogen. Evidence of sexual reproduction including low clonality, Hardy-Weinberg equilibrium within loci and gametic equilibrium between loci, indicated the predominance of a mixed reproductive system in all populations. In addition, we assessed the adaptive potential of the Brazilian populations of R. oryzae-sativae to emerge as a pathogen to Urochloa spp. (signalgrass) based on greenhouse aggressiveness assays. The Brazilian populations of R. oryzae-sativae were probably only incipiently adapted as a pathogen to Urochloa spp. Comparison between R and Q showed the predominance of diversifying selection in the divergence between the two populations of R. oryzae-sativae from Brazil.

RESUMO Este estudo teve o objetivo de selecionar isolados do fungo entomopatogênico Metarhizium anisopliae para o controle de adultos de Rhynchophorus palmarum (L.) (Coleoptera: Curculionidae) e avaliar a compatibilidade de agrotóxicos utilizados nesta cultura com o isolado que ocasionasse maior mortalidade dos adultos. Para tal, adultos do inseto foram imersos em suspensões de seis isolados do fungo na concentração de 109 conídios.mL-1 e, após 24 dias, o isolado IBCB 348 causou maior mortalidade (87,5%) e foi utilizado para o teste de compatilibidade, por meio do cálculo da fórmula de T, com inseticidas, herbicidas e fungicidas comerciais utilizados na cultura. Nenhum dos fungicidas e herbicidas testados foram compatíveis com o patógeno. Os inseticidas Calypso, Dipterex 500 e Sevin 480 SC, na concentração mínima recomendada pelo fabricante, foram os únicos produtos classificados como compatíveis com o isolado IBCB 348 de M. anisopliae.

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Patogenicidade cruzada de Ceratobasidium spp. do caquizeiro (Diospyros kaki) e do chá(Camellia sinensis) e reação de cultivares de caqui ao patógeno. ABSTRACTThe fungus Ceratobasidium spp. causes the white-thread blight disease, which affects several fruit trees, coffee and tea crops. This disease frequently occurs in zones of high precipitation and temperatures, typical of the tropical forest regions such as the Amazon and the Atlantic Forests. In São Paulo State, Brazil, this disease was reported by the first time affecting kaki plants in Mogi das Cruzes county. The objective of this study was to test the cross-pathogenicity Souza, E.C.; Basseto, M.A.; Boliani, A.C.; Takada, H.M.; Ceresini, P.C.. Cross pathogenicity of Ceratobasidium spp. from kaki (Diospyros kaki) and tea (Camellia sinensis) and reaction of kaki varieties to the pathogen. Summa Phytopathologica, v.35, n.

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