Building bridges between environmental and political agendas is essential nowadays in face of the increasing human pressure on natural environments, including wetlands. Wetlands provide critical ecosystem services for humanity and can generate a considerable direct or indirect income to the local communities. To meet many of the sustainable development goals, we need to move our trajectory from the current environmental destructive development to a wiser wetland use. The current article contain a proposed agenda for the Pantanal aiming the improvement of public policy for conservation in the Pantanal, one of the largest, most diverse, and continuous inland wetland in the world. We suggest and discuss a list of 11 essential interfaces between science, policy, and development in region linked to the proposed agenda. We believe that a functional science network can booster the collaborative capability to generate creative ideas and solutions to address the big challenges faced by the Pantanal wetland.

A sustainable alternative to improve yield and the nutritive value of forage is the use of plant growth-promoting bacteria (PGPB) that release nutrients, synthesize plant hormones and protect against phytopathogens (among other mechanisms). Azospirillum genus is considered an important PGPB, due to the beneficial effects observed when inoculated in several plants. The aim of this study was to evaluate the diversity of new Azospirillum isolates and select bacteria according to the plant growth promotion ability in three forage species from the Brazilian Pantanal floodplain: Axonopus purpusii, Hymenachne amplexicaulis and Mesosetum chaseae. The identification of bacterial isolates was performed using specific primers for Azospirillum in PCR reactions and partial sequencing of the 16S rRNA and nifH genes. The isolates were evaluated in vitro considering biological nitrogen fixation (BNF) and indole-3-acetic acid (IAA) production. Based on the results of BNF and IAA, selected isolates and two reference strains were tested by inoculation. At 31 days after planting the plant height, shoot dry matter, shoot protein content and root volume were evaluated. All isolates were able to fix nitrogen and produce IAA, with values ranging from 25.86 to 51.26 mg N mL and 107-1038 µmol L, respectively. The inoculation of H. amplexicaulis and A. purpusii increased root volume and shoot dry matter. There were positive effects of Azospirillum inoculation on Mesosetum chaseae regarding plant height, shoot dry matter and root volume. Isolates MAY1, MAY3 and MAY12 were considered promising for subsequent inoculation studies in field conditions.

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Plant species that naturally occur in the brazilian Caatinga (xeric shrubland) adapt in several ways to these harsh conditions, and that can be exploited to increase crop production. among the strategic adaptations to confront low water availability, desiccation tolerance stands out. Up to now, the association of those species with beneficial soil microorganisms is not well understood. The aim of this study was to characterize Tripogon spicatus diazotrophic bacterial isolates from the Caatinga biome and evaluate their ability to promote plant growth in rice. sixteen bacterial isolates were studied in regard to their taxonomic position by partial sequencing of the 16s rRna gene, putative diazotrophic capacity, in vitro

RESUMOEste trabalho teve por objetivo avaliar a ocorrência e a diversidade genética de bactérias fixadoras de N 2 associadas às gramíneas nativas Elyonurus muticus (capim carona) e Axonopus purpusii (capim mimoso) e à gramínea exótica Brachiaria humidicola (braquiária) que formam as pastagens na região da Nhecolândia. As coletas das plantas e solo foram feitas nos períodos de seca e de cheia para determinar a população de bactérias diazotróficas. Identificaram-se Azospirillum brasilense, A. lipoferum, A. amazonense, Herbaspirillum spp., Burkholderia spp. em amostras de solo, raízes e folhas das três espécies forrageiras. As populações dessas bactérias foram menores na época da cheia em comparação com a época da seca. A diversidade genética das bactérias isoladas foi avaliada por meio da técnica de análise de restrição do DNA ribossomal amplificado (ARDRA). Os isolados foram divididos em cinco grupos genotípicos distintos. Os isolados de A. brasilense e A. lipoferum apresentaram cerca de 50 % de similaridade, enquanto A. amazonense formou um grupo a parte, com apenas 25 % de similaridade em relação ao grupo das espécies do gênero. As bactérias do gênero Herbaspirillum formaram um grupo isolado com apenas 25 % de similaridade em relação ao gênero Azospirillum. O quinto grupo foi formado por apenas um isolado com 25 % de similaridade em relação aos demais.

The study of plant growth-promoting bacteria (PGPB) can identify outstanding bacteria for crops. For forage grasses adapted to drylands, the selection of PGPB can increase the field performance of pastures. The aim of this study was to isolate, and characterise at molecular, biochemical and symbiotic levels, diazotrophic bacteria obtained from buffel grass (Cenchrus ciliaris), sorghum (Sorghum bicolor) and Tifton 85 (Cynodon spp.) from Brazilian semi-arid region fields. Field-grown plants were collected, and the roots were surface-disinfected, crushed and inoculated in a semi-solid medium. After the formation and confirmation of microaerophilic pellicles, the bacteria were isolated and purified. All bacterial isolates were subjected to nifH gene amplification and identified by their partial 16S rRNA gene sequences. The bacteria were evaluated for the production of auxins and siderophores, calcium phosphate solubilisation, and diazotrophic ability as ‘in vitro’ plant growth-promotion traits. A plant inoculation assay was conducted to assess the plant growth-promotion abilities of the bacterial isolates. Twenty-one bacterial isolates harboured the nifH gene (nifH+), among which nine were obtained from sorghum, eight from buffel grass, and four from Tifton 85. The bacterial isolates were classified as Bacillus (8), Stenotrophomonas (7), Agrobacterium (4), Cellulomonas (1) and Paenibacillus (1). All were shown to be auxin producers, with 14 isolates showing diazotrophic capacity ‘in vitro’. Fourteen isolates increased plant N content, but the bacterial strains ESA 392 and ESA 398 (Bacillus), ESA 397 and ESA 407 (Stenotrophomonas), and ESA 401 (Agrobacterium) were shown to promote both plant growth and N nutrition. These strains are candidates for further assays to evaluate their agronomic performance under field conditions, aiming inoculant production for forage grasses in drylands.

GALEANO, R. M. S.; CAMPELO, A. P. S.; MACKERT, A.; BRASIL, M. S. Desenvolvimento inicial e quantificação de proteínas do milho após inoculação com novas estirpes de Azospirillum brasilense. Revista de Agricultura Neotropical, Cassilândia-MS, v. 6, n. 2, p. 95-99, abr./jun. 2019. RESUMOO uso indiscriminado de fertilizantes nitrogenados na cultura do milho ocasiona poluição ambiental. A fixação biológica do nitrogênio (FBN) é uma alternativa para a redução desses químicos em campo. Bactérias do gênero Azospirillum estão entre as mais importantes envolvidas na FBN em gramíneas. Portanto, o objetivo do trabalho foi analisar a germinação e o desenvolvimento inicial, bem como quantificar as proteínas totais do milho após a inoculação com diferentes estirpes de Azospirillum brasilense isoladas de gramíneas do Pantanal Sul-Mato-Grossense. O experimento foi inteiramente casualizado com três repetições de 50 sementes para os seguintes tratamentos: testemunha sem inoculação; inoculação com estirpes MAY1, MAY12 e BR-11001; e inoculante comercial contendo as estirpes AbV5 e AbV6. Os parâmetros avaliados foram germinação de sementes, primeira contagem de germinação, massa seca da parte aérea e das raízes de plântulas e proteínas totais das folhas. A inoculação não influenciou significativamente na germinação. A massa seca da parte aérea e de raízes foi maior com inoculação de MAY12 e inoculante comercial. Resultados na quantificação de proteína mostraram que sementes inoculadas com MAY12 (3628 µg mL -1 ) possuem maiores concentrações de proteínas totais. Portanto, a inoculação com MAY12 proporcionou efeitos positivos de incremento de massa seca e proteínas totais.Palavras-chave: bactérias promotoras de crescimento, fixação biológica do nitrogênio, Zea mays. ABSTRACTThe indiscriminate use of nitrogen fertilizers in the corn crop causes environmental pollution. Biological nitrogen fixation (BNF) is an alternative for the reduction of these chemicals in the field. Bacteria of the genus Azospirillum are among the most important involved in BNF in grasses. Therefore, the objective of this work was to analyze germination and initial development, as well as to quantify total corn proteins after inoculation with different strains of Azospirillum brasilense isolated from grasses from Pantanal Sul-Mato-Grossense. The experiment was completely randomized with 3 replicates of 50 seeds per treatment: control without inoculation; inoculation with MAY1, MAY12 and BR-11001 strains; and commercial inoculant containing the strains AbV5 and AbV6. The parameters evaluated were seed germination (%), first germination count, dry mass of shoots and roots and total proteins of leaves. Inoculation didn't significantly influence germination. Aerial shoot and root dry mass was higher with inoculation of MAY12 and commercial inoculant. Results of protein quantification showed that seeds inoculated with MAY12 (3628 μg mL -1 ) showed higher concentrations of total proteins. Therefore, inoculation with MAY12 provided positive effects of increasing dry ma...

Carbon sources are exuded and deposited by different soil cover plants. They promote growth, diversity and enhancement of soil microbial community functionality, due to organic matter degradation by participating in major biochemical cycles and the availability of inorganic nutrients to plants. In this way, it is necessary to evaluate the microbiological attributes of the soil after cover cropping, which allows for surveying and monitoring the soil quality, thereby enabling rapid responses in relation to managing changes in the soil. Thus, the objective of this study was to evaluate soil microbiological attributes and soybean grain yield under the influence of different cover crops. The experiment was installed in the year 2015. The treatments were constituted by the following vegetation coverages: sorghum, millet, Urochloa ruziziensis, forage turnip, Urochloa brizantha, crambe and fallow area, with cover crops sown in succession to the soybean crop for three years prior to the date of installation of the experiment .The evaluated parameters were soil microbial biomass carbon, soil basal respiration, metabolic quotient, enzymatic activity of acid phosphatase and soil β-glucosidase, plant phytomass produced by the different cover crops and soybean yield in each area. The use of cover crops promotes higher soybean yield. The microbial activity and its efficiency were modulated according to the type of cover crop used. Soil under sorghum mulch provided lower microbial efficiency. The U. ruziziensis plant residues remain for less time on the soil. The results show that U. brizantha may be the most suitable for its use as a soil cover plant, providing improvements in its attributes.