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The soil-borne fungi, Setophoma terrestris and Fusarium spp., are often associated with pink root, although the etiology of the disease remains doubtful. While recognized as the primary inoculum, studies show conflicting views on the formation of chlamydospores and microsclerotia in Setophoma. Therefore, this study aims to clarify the etiology of the pink root of garlic and onion and the formation of chlamydospores and microsclerotia in Setophoma. The isolates were obtained from symptomatic tissues of garlic, leeks, brachiaria, onions, chives, and maize collected from seven different states in Brazil. Representative isolates were selected for pathogenicity tests. Sequence comparison of the tubulin gene showed Setophoma (n = 50) and Fusarium clades (n = 25). Garlic and onion plants inoculated with Setophoma showed pink root symptoms, while plants inoculated with different Fusarium isolates remained asymptomatic. Multigene analysis of pathogenic isolates confirms that only Setophoma terrestris causes pink root in garlic and onion. In addition, brachiaria, chives, and leeks are newly identified hosts of this pathogen in Brazil. To our knowledge, the main sources of primary inoculum of the disease are chlamydospores, pycnidia, colonized roots of garlic, onion, and plant debris of susceptible crops. The new information obtained in this study will be fundamental for researchers in the development of genotypes that are resistant to pink root and will help the efficient management of the disease.

Sida mottle virus (SiMoV) and Sida micrantha mosaic virus (SiMMV) are major Brazilian begomoviruses (Geminiviridae). However, the range of DNA–A identity of isolates of these viruses (81–100%) is not in agreement with the current criteria for Begomovirus species demarcation (<91%). To clarify this putative classification problem, we performed a comprehensive set of molecular analyses with all 53 publicly available isolates (with complete DNA–A genomes) designated as either SiMoV or SiMMV (including novel isolates obtained herein from nationwide metagenomics-based studies). Two well-defined phylogenetic clusters were identified. The SiMMV complex (n = 47) comprises a wide range of strains (with a continuum variation of 88.8–100% identity) infecting members of five botanical families (Malvaceae, Solanaceae, Fabaceae, Oxalidaceae, and Passifloraceae). The SiMoV group now comprises eight isolates (90–100% identity) restricted to Malvaceae hosts, including one former reference SiMMV isolate (gb|NC_077711) and SP77 (gb|FN557522; erroneously named as “true SiMMV”). Iteron analyses of metagenomics-derived information allowed for the discovery of the missing DNA–B cognate of SiMoV (93.5% intergenic region identity), confirming its bipartite nature. Henceforth, the correct identification of SiMoV and SiMMV isolates will be a crucial element for effective classical and biotech resistance breeding of the viral host species.

Foliar anthracnose is one of the main diseases of onion (Allium cepa L.) under tropical and subtropical conditions. Thus far, only Colletotrichum gloeosporioides has been reported as the causal agent of this disease in Brazil. However, there are no extensive studies characterizing Colletotrichum isolates associated with onion anthracnose in the country. Here, 38 Colletotrichum isolates obtained from onion plants displaying foliar anthracnose across major Brazilian onion-producing regions were characterized using morphometric and molecular information. The Bayesian and Maximum Liklihood methods were used for an initial analysis of the β-tubulin gene (tub2) sequences of all isolates, resulting in the discrimination of nine haplotypes. Three haplotypes grouped with the reference species of the C. acutatum complex and six with the C. gloeosporioides complex. Sequences of either the glyceraldehyde-3-phosphate dehydrogenase (gapdh), actin (act), and calmodulin genes or the intergenic spacer (IGS) region between DNA lyase (apn2) gene and the mating-type mat1–2-1 locus were used to characterize a subset of isolates representing these nine distinct tub2 gene haplotypes. These analyses revealed five anthracnose-inducing Colletotrichum species, including three members of the C. acutatum species complex (C. nymphaeae, C. scovillei, and C. tamarilloi) and two of the C. gloeosporioides species complex (C. fructicola and C. theobromicola). Bioassays confirmed that all these Colletotrichum species are pathogenic to onion, inducing typical anthracnose symptoms on bulbs and leaves. Twenty-six out of 38 isolates were identified as C. theobromicola, indicating this fungus as the prevalent anthracnose pathogen under Brazilian conditions. This Colletotrichum species diversity will affect anthracnose management strategies, including chemical and cultural control as well as the identification and deployment of onion cultivars with species-specific and/or wide-spectrum tolerance/resistance.

Grafting has been increasingly used to overcome soilborne pathogens. The commercial rootstock hybrids AF-8253 (Sakata) and Fortaleza (Takii), as well as Embrapa?s new hybrid, BRS Acará, were evaluated as rootstocks for the bell pepper hybrids Margarita (Syngenta) and Pampa (Clause) as scions, under natural infestation of Ralstonia pseudosolanacearum, as well as upon artificial inoculation with a) ten Ralstonia isolates, b) one Phytophthora capsici isolate, c) Meloidogyne incognita race 1, and d) Meloidogyne enterolobii (only rootstocks for c and d). Grafted bell peppers consistently showcased a higher productivity than did non-grafted ones under natural R. pseudosolanacearum infestation, and the rootstock genotype affected fruit size distribution. Rootstocks presented higher resistance than did commercial bell pepper hybrids (scions) for 6 out of 10 Ralstonia isolates. AF-8253 and BRS Acará displayed an immunelike response to P. capsici, while Fortaleza was moderately resistant (25% symptomatic plants) and the bell pepper hybrids (scions) were susceptible (100% symptomatic plants). Rootstocks were immune to M. incognita race 1, but slightly (AF-8253 and BRS Acará) or moderately (Fortaleza) resistant to M. enterolobii. Grafting with BRS Acará, as well as with AF-8253 or Fortaleza, is recommended for managing bacterial wilt, Phytophthora blight, and root-knot nematodes.

Anthracnose caused by Colletotrichum species is the most important disease of chayote (Sicyos edulis) in Brazil. The etiology of chayote anthracnose has been assigned to the species C. orbiculare, an important plant pathogenic fungus also reported as the causal agent of anthracnose in other cucurbits worldwide. However, there is no recent survey of the Colletotrichum species causing anthracnose in chayote in Brazil. In this study, Colletotrichum isolates associated with anthracnose on the fruit and leaves of chayote, from various producing regions in Brazil, were collected and identified. Haplotype analysis based on sequences of the β-tubulin genomic region (TUB2) of 44 Colletotrichum isolates was carried out as a first measure of genetic diversity. A subset of 22 isolates were sequenced using the partial sequences of actin (ACT), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and the rDNA ITS (ITS) region. Maximum likelihood analysis was performed using the concatenated sequences. The multilocus sequence analysis revealed four previously described species, Colletotrichum chrysophilum, C. menezesiae, C. plurivorum, and C. karsti, and two novel species, named C. cucurbitacearum and C. sicyi. All species were able to induce typical symptoms of anthracnose in chayote fruits but varied in their aggressiveness. The species C. menezesiae and C. sicyi were the most aggressive, while C. plurivorum was the least aggressive. The species C. orbiculare was not found to cause chayote anthracnose in Brazil.

Yield losses induced by a complex of begomoviruses are observed across all major tomato-producing areas in Brazil. Tomato severe rugose virus (ToSRV) is the most widespread begomovirus in the country. Conversely, tomato common mosaic virus (ToCmMV) displays a more restricted geographical distribution to areas associated with the Atlantic Rain Forest (ARF) biome, encompassing the States of Espírito Santo–ES, Minas Gerais–MG, and Rio de Janeiro–RJ. Here, we characterized 277 tomato-infecting isolates collected in fields located within the ARF biome from 2006 to 2018. ToSRV displayed the highest prevalence (n = 157), followed by ToCmMV (n = 95) and tomato interveinal chlorosis virus (n = 14). Four other begomoviruses were also detected, but with very low incidences. ToCmMV was the predominant begomovirus in the ARF biome up to 2014–2015 with very low ToSRV incidence. Subsequently, ToSRV became the most prevalent species in ES and RJ, but ToCmMV was still predominating in the “Zona da Mata” meso-region in MG. Due to the remarkable endemic distribution of ToCmMV, we carried out phylogeographical studies of this virus using information from all 28 available isolates with complete DNA–A sequences. The closest common ancestor of ToCmMV was more likely originated around Coimbra–MG area ≈ 25 years before the formal report of this viral species. So far, all surveys indicated tomatoes as the only natural hosts of ToCmMV with outbreaks occurring mainly (but not exclusively) in highland areas. ToSRV shows a more widespread incidence across both highland and lowland areas of the ARF biome.

Fusarium oxysporum f. sp. lycopersici (FOL) races 1 and 2 were, up to recent years, the only pathogenic Fusaria associated with tomatoes (Solanum lycopersicum L.) in Brazil. However, recent outbreaks of F. oxysporum isolates with the ability to breakdown the I–2-mediated resistance prompted us to conduct nationwide surveys of the pathogens associated with vascular wilt of tomatoes. During these surveys, eight atypical F. oxysporum isolates (collected across five tomato–producing Brazilian states) displayed a peculiar ability of infecting accessions carrying the I–3 and I–7 genes (controlling resistance to FOL race 3 isolates). These observations suggested the involvement of either a new FOL race or of F. oxysporum f. sp. radicis-lycopersici (FORL) isolates. Koch’s postulates were fulfilled for these eight atypical isolates via root dipping inoculation (106 conidia mL− 1) of seedlings from two tomato cultivars ‘Ponderosa’ and ‘Dominador’. All eight isolates induced crown-rot symptoms only in ‘Ponderosa’, but not in ‘Dominador’ (which is resistant to FORL). To confirm the FORL identity, PCR assays were done using a set of race-specific and forma specialis-specific primers. A single amplicon of ≈ 947 bp was observed with the primer pair Sprl only with DNA template obtained from standard FORL isolates and from the eight atypical isolates, confirming the first detection of this forma specialis in Brazil. The geographical distribution of FORL isolates across major tomato–producing areas may require the incorporation of resistant factors into adapted cultivars.

Civilizations are large energy consumers, so the more civilized a people, the greater their energy consumption. However, studies have shown that the way energy is produced is polluting and focused on finite resources. This study aimed to take stock of the scientific literature on renewable energies, identifying their advantages and disadvantages. The conceptual bibliographic method was used in its four stages: formulation of guiding questions, collection and organization of data, and presentation of responses generated by handling data obtained from Google Scholar and Periódico Capes. The results showed that a) renewable energy comes from a natural cyclothymic source, b) the advantages of renewable energy are almost all of an environmental nature, and c) the disadvantages are of an economic-financial nature. The conclusion shows that the time has come for a decision to be made between paying the high price of environmental sustainability or continuing with the lower costs of compromising the continuity of life on the planet.

We are living in a time of expanding awareness that natural resources are finite and tend to become increasingly scarce if their uses continue to be made in a disorderly and inconsequential manner. In this sense, this study aimed to make a brief and consistent survey of the literature on the bioeconomy, focusing on its applications and objectives of these applications. To this end, it applied the four stages of the scientific-technological method: formulating guiding research questions, collecting data in scientific databases, organizing it following semantic principles, and generating responses. The results showed that a) bioeconomy is seen in seven different and integrated ways, b) ten distinct forms are well cataloged by science, and c) the objectives of these applications vary by the bioeconomic purpose. The conclusion shows that the bioeconomy is a system that converts natural resources into products by the principles of sustainability, which can be seen in all applications in the literature.

Fusarium oxysporum f. sp. vasinfectum (FOV) is one the most destructive okra (Abelmoschus esculentus) pathogens in Brazil. Fifty-four okra accessions were evaluated for resistance to FOV. Greenhouse screening was initially carried out with one FOV isolate ('Fus-194'). Inoculation (in all assays) was carried out with 21-day-old plantlets, using the root-dipping inoculation technique. Thirty-three accessions displaying differential responses in the first screening were re-evaluated in two additional assays, using two FOV isolates ('Fus-194' and 'Fus-201'). Twelve accessions were rated as highly to intermediately resistant to 'Fus-194' during the dry/moderate temperature season, whereas nine accessions were classified as highly to intermediately resistant to 'Fus-201'. In the assay carried out in the wet and warm season, 72% of the accessions were classified as having high and intermediate resistance to 'Fus-194', and 32% were resistant to 'Fus-201'. The accessions 'Santa Cruz-47', 'BR-2399' and 'BR-1449' were the most promising resistance sources. Fusarium oxysporum f. sp. vasinfectum (FOV) é um dos patógenos mais destrutivos do quiabeiro (Abelmoschus esculentus) no Brasil. Cinquenta e quatro acessos de quiabeiro foram avaliados quanto à resistência a FOV em casa de vegetação. Inicialmente foi conduzida uma seleção com o isolado 'Fus-194'. Trinta e três acessos, que foram resistentes na seleção inicial, foram reavaliadas em dois ensaios adicionais (sob duas condições de ambiente), utilizando dois isolados de FOV. Destes, onze acessos foram classificadas como altamente ou medianamente resistentes ao isolado 'Fus-194' em agosto (estação seca e com temperatura moderada), enquanto que 28% dos acessos foram classificados como altamente ou medianamente resistentes ao isolado 'Fus-201'. No ensaio conduzido na estação úmida e quente, 72% dos acessos apresentaram reação de alta a média resistência a 'Fus-194', enquanto que 32% foram resistentes a 'Fus-201'. A cultivar 'Santa Cruz-47' e os acessos 'BR-2399' e 'BR-1449' foram as fontes de resistência mais promissoras.