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Brazil stands out in research, industrial development, and farmers' use of microbial inoculants, with an emphasis on getting benefits from the biological nitrogen fixation process with the soybean crop. Nowadays, about 140 million doses of inoculants are commercialized annually for the soybean in the country, and strain identification is achieved by rep-PCR, an effective but time-consuming method. Aiming to develop an easy, low-cost, and low-time-consuming method, we used a complete genome-based approach based on the unequivocal identification of unique genes present in the genomes of each of the four Bradyrhizobium strains used in commercial inoculants: Bradyrhizobium elkanii strains SEMIA 587 and SEMIA 5019, Bradyrhizobium japonicum SEMIA 5079, and Bradyrhizobium diazoefficiens SEMIA 5080. The unique pairs of primers able to amplify genomic regions of different sizes allowed the identification of the four strains in a simple multiplex polymerase chain reaction (PCR). Validation was confirmed by using single colonies, multiple cultures, and commercial inoculants. The number of labor hours of a technician was 3.08 times higher, and the final cost was 3.25 times higher in the rep-PCR than in the multiplex PCR. Most importantly, the results for multiplex PCR were obtained on the same day, in contrast with 15 days in the traditional methodology. The genomic approach developed can be easily applied to a variety of microbial inoculants worldwide, in addition to studies of ecology and evaluation of the competitiveness of the strains.

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Baculoviruses are insect-specific pathogens widely used in biotechnology. In particular, the Autographa californica nucleopolyhedrovirus (AcMNPV) has been exploited as a platform for bio-inputs production. This is why the improvement of the technologies used for the production of recombinant baculoviruses takes on particular relevance. To achieve this goal, we developed a highly versatile baculoviral transfer vector generation system called PluriBAC. The PluriBAC system consists of three insert entry levels using Golden Gate assembly technology. The wide availability of vectors and sticky ends allows enough versatility to combine more than four different promoters, genes of interest, and terminator sequences. Here, we report not only the rational design of the PluriBAC system but also its use for the generation of baculoviral reporter vectors applied to different fields of biotechnology. We demonstrated that recombinant AcMNPV baculoviruses generated with the PluriBAC system were capable of infecting Spodoptera frugiperda larvae. On the other hand, we found that the recombinant budded virions (BV) generated using our system were capable of transducing different types of tumor and normal cells both in vitro and in vivo. Our findings suggest that the PluriBAC system could constitute a versatile tool for the generation of insecticide and gene therapy vectors.

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The use of products of microbial origin, bacteria, for agriculture has grown exponentially in the world, and in Brazil this growth is significant. In recent years,several companies have settled in the country and started to develop different products in this segment. The producer has the possibility of multiplying bacteria on the farms themselves in a process called on farm, a homemade way of multiplying bacteria. The objective of this studywas to evaluate the efficiency of the mixtures produced through the on farmmethod of multiplication of microorganisms from inoculants based on Azospirillumwith different culture media. For this, three culture media were used: commercial product Multibacter®, yeast syrup plus sugar and yeast syrup, which were subsequently quantified. The syrups were produced in the onfarmsystem, the sterilization of the place of packaging and allocation of the bioreactors was carried out, the samples of the syrups were diluted for incubation and the preparation of the TSA(Trypticasein Soy Agar)also took place. It was possible to conclude that the non-sterile culture media do not present satisfactory results for the multiplication of on farmmicroorganisms with Azospirillumsyrups. Colony forming units are not parameters to indicate viability for non-sterile culture media.(AU)

O uso de produtos de origem microbiana, bactérias, para a agricultura tem crescido exponencialmente no mundo, e no Brasil este crescimento é significativo. Nos últimos anos várias empresas se instalaram no país e passaram a desenvolver diversos produtos neste segmento. O produtor, tem a possibilidade de multiplicar bactérias nas próprias fazendas em um processo chamado on farm,uma forma caseira de multiplicar bactérias. O objetivo deste estudo foi avaliar a eficiência das caldas produzidas através do método on farmde multiplicação de microrganismos de inoculantes a base de Azospirillumcom diferentes meios de culturas. Para isto foram utilizados três meios de cultura: produto comercial Multibacter®, calda de levedura mais açúcar e calda de levedura, os quais posteriormente foram quantificados. As caldas foram produzidas no sistema on farm, foi realizada a esterilização do local acondicionamento e alocação dos biorreatores, as amostras das caldas foram diluídas para incubação e também ocorreu o preparo do TSA (Trypticasein Soy Agar). Foi possível concluir que os meios de cultura não estéreis não apresentam resultados satisfatórios para a multiplicação de microrganismos on farmcom caldas de Azospirillum. Unidades formadoras de colônias não são parâmetros para indicar a viabilidade para meios de cultura não estéreis.(AU)

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Considering a scenario where there is a low availability and increasing costs of fertilizers in the global agricultural market, as well as a finitude of important natural resources, such as phosphorus (P), this study tested the effect of the inoculation of rhizospheric or endophytic microorganisms isolated from Hymenaea courbaril and Butia purpurascens on the growth promotion of Glycine max (L.) Merr. The tests were conducted in a controlled greenhouse system, and the effects of biofertilization were evaluated using the following parameters: dry biomass, nutritional content, and photochemical and photosynthetic performance of plants. Seed biopriming was performed with four bacterial and four fungal isolates, and the results were compared to those of seeds treated with the commercial product Biomaphos®. Overall, microbial inoculation had a positive effect on biomass accumulation in G. max, especially in strains PA12 (Paenibacillus alvei), SC5 (Bacillus cereus), and SC15 (Penicillium sheari). The non-inoculated control plants accumulated less nutrients, both in the whole plant and aerial part, and had reduced chlorophyll index and low photosynthetic rate (A) and photochemical efficiency. Strains PA12 (P. alvei), SC5 (B. cereus), and 328EF (Codinaeopsis sp.) stood out in the optimization of nutrient concentration, transpiration rate, and stomatal conductance. Plants inoculated with the bacterial strains PA12 (P. alvei) and SC5 (B. cereus) and with the fungal strains 328EF (Codinaeopsis sp.) and SC15 (P. sheari) showed the closest pattern to that observed in plants treated with Biomaphos®, with the same trend of direction of the means associated with chlorophyll index, (A), dry mass, and concentration of important nutrients such as N, P, and Mg. We recommend the use of these isolates in field tests to validate these strains for the production of biological inoculants as part of the portfolio of bioinputs available for G. max.

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Abstract Quality evaluation of commercial inoculants is essential to warrant an adequate cropresponse to inoculation within a biosecurity framework. In this sense, this work is aimed at standardizing and validating the drop plate method for the enumeration of Azospirillum viable cellsas an alternative to the spread plate technique, which is currently proposed in the consensusprotocol of the REDCAI network. Between 14 and 25 private and public laboratories partici-pated in three independent trials. We obtained consistent and robust results that allowed toconfirm that both techniques are equivalent, concluding that the drop plate method is an alternative enumeration technique that is adequate to be included in the abovementioned consensusprotocol.

Resumen La evaluación de la calidad de los inoculantes comerciales es fundamental para garantizar una adecuada respuesta de los cultivos a la inoculación dentro de un marco de bioseguridad. En este sentido, el objetivo de este trabajo fue la estandarización y validación de la técnica de la microgota para la cuantificación de Azospirillum como metodología alternativa a la técnica de siembra en superficie, propuesta actualmente en el protocolo consenso de la Red de Calidad de Inoculantes, REDCAI. Entre 14 y 25 laboratorios, tanto privados como públicos, participaron de tres ensayos independientes. A partir de ellos se obtuvieron resultados reproducibles y robustos que permiten confirmar que ambas técnicas son equivalentes y concluir que la técnica de recuento por la microgota es una alternativa adecuada para ser incluida dentro del mencionado protocolo consenso.

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Quality evaluation of commercial inoculants is essential to warrant an adequate crop response to inoculation within a biosecurity framework. In this sense, this work is aimed at standardizing and validating the drop plate method for the enumeration of Azospirillum viable cells as an alternative to the spread plate technique, which is currently proposed in the consensus protocol of the REDCAI network. Between 14 and 25 private and public laboratories participated in three independent trials. We obtained consistent and robust results that allowed to confirm that both techniques are equivalent, concluding that the drop plate method is an alternative enumeration technique that is adequate to be included in the abovementioned consensus protocol.

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The problems generated by the inappropriate use of agrotoxins and imported and costly chemical products to guarantee the health of the plants have been a great challenge for Brazilian farmers. The growing development and supply of new products of biological origin on the market is strengthening the portfolio of available bio-inputs for the production system. Among the benefits of the use of bioinputs is the greater sustainability of the productive system, with less frequent outbreaks of pests, reduction in application costs, greater efficiency of biological nitrogen fixation and promotion of plant growth. These benefits will promote greater profitability and contribute to a more sustainable agriculture. In this way, this review intends to discover some of the techniques that can be used in agriculture within two preceitos of sustainable agriculture.(AU)

Os problemas gerados pelo uso inadequado de agrotóxicos e produtos químicos importados e custosos para garantir a sanidade das plantas têm sido um grande desafio para os agricultores brasileiros. O crescente desenvolvimento e oferta de novos produtos de origem biológica no mercado vêm fortalecendo o portfólio de bioinsumos disponíveis para o sistema de produção. Entre os benefíciosda utilização de bioinsumos está a maior sustentabilidade do sistema produtivo, com surtos de pragas menos frequentes, redução dos custos de aplicação, maior eficiência da fixação biológica de nitrogênio e promoção de crescimento de plantas. Esses benefícios irão propiciar maior lucratividade e contribuir para uma agricultura mais sustentável. Dessa forma, esta revisão tem o intuito de descrever algumas das técnicas que podem ser utilizadas na agricultura dentro dos preceitos da agricultura sustentável.(AU)

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The sustainable development of agriculture can be stimulated by the great market availability of bio-inputs, including phosphate-solubilizing microbial strains. However, these strains are currently selected using imprecise and questionable solubilization methodologies in solid or liquid media. We hypothesized that the hydroponic system could be a more efficient methodology for selecting phosphate-solubilizing strains as plant growth promoters. This methodology was tested using the plant Glycine max as a model. The growth-promoting potential of the strains was compared with that of the Biomaphos® commercial microbial mixture. The obtained calcium phosphate (CaHPO4) solubilization results using the hydroponic system were inconsistent with those observed in solid and liquid media. However, the tests in liquid medium demonstrated poor performances of Codinaeopsis sp. (328EF) and Hamigera insecticola (33EF) in reducing pH and solubilizing CaHPO4, which corroborates with the effects of biotic stress observed in G. max plants inoculated with these strains. Nevertheless, the hydroponic system allowed the characterization of Paenibacillus alvei (PA12), which is also efficient in solubilization in a liquid medium. The bacterium Lysinibacillus fusiformis (PA26) was the most effective in CaHPO4 solubilization owing to the higher phosphorus (P) absorption, growth promotion, and physiological performance observed in plants inoculated with this bacterium. The hydroponic method proved to be superior in selecting solubilizing strains, allowing the assessment of multiple patterns, such as nutritional level, growth, photosynthetic performance, and anatomical variation in plants, and even the detection of biotic stress responses to inoculation, obtaining strains with higher growth promotion potential than Biomaphos®. This study proposed a new approach to confirm the solubilizing activity of microorganisms previously selected in vitro and potentially intended for the bio-input market that are useful in P availability for important crops, such as soybeans.