Background The importance of organic farming has increased through the years to promote food security allied with minimal harm to the ecosystem. Besides the environmental benefits, a recurring problem associated with organic management is the unsatisfactory yield. A possible solution may rely on the soil microbiome, which presents a crucial role in the soil system. Here, we aimed to evaluate the soil bacterial community structure and composition under organic and conventional farming, considering the tropical climate and tropical soil. Methodology Our organic management treatments were composed by composted poultry manure and green manure with Bokashi. Both organic treatments were based on low nitrogen inputs. We evaluated the soil bacterial community composition by high-throughput sequencing of 16S rRNA genes, soil fertility, and soil enzyme activity in two organic farming systems, one conventional and the last transitional from conventional to organic. Results We observed that both organic systems evaluated in this study, have higher yield than the conventional treatment, even in a year with drought conditions. These yield results are highly correlated with changes in soil chemical properties and enzymatic activity. The attributes pH, Ca, P, alkaline phosphatase, and β- glucosidase activity are positively correlated with organic systems, while K and Al are correlated with conventional treatment. Also, our results show in the organic systems the changes in the soil bacteria community, being phyla Acidobacteria, Firmicutes, Nitrospirae, and Rokubacteria the most abundant. These phyla were correlated with soil biochemical changes in the organic systems, helping to increase crop yields. Conclusion Different organic management systems, (the so-called natural and organic management systems, which use distinct organic sources), shift the soil bacterial community composition, implying changes in their functionalities. Also, our results contributed to the identification of target bacterial groups and changes in soil chemical properties and enzymatic activity in a trophic organic farming system, which may contribute to higher crop yields.

Tendo em vista a utilização dos fungos micorrízicos arbusculares atuando como bioindicadores de qualidade do solo, o objetivo deste trabalho foi avaliar os efeitos sobre a porcentagem de colonização micorrízica, número de esporos viáveis e glomalina facilmente extraível de dois diferentes sistemas de cultivo de milho: milho transgênico em cultivo convencional e milho variedade em cultivo alternativo. Os tratamentos foram semeados em duas faixas paralelas e contíguas, com dois hectares cada, em condições semelhantes de fertilidade de solo e relevo. No cultivo convencional o milho transgênico foi semeado com adubação na linha de 280 kg.ha-1 do fertilizante fórmula NPK 7-28-16, 8% Ca, 1,5% S e 0,3% Zn. Foi utilizado glifosato juntamente com o inseticida Chlorantraniliprole + lambda-cialotrina para o controle de mato e lagartas. No cultivo alternativo o solo foi preparado com a aplicação de 500 kg.ha-1 do condicionador de solo Bokashi e posterior gradagem e nivelamento. Foi aplicado o herbicida atrazina para contenção do mato e uma pulverização de inseticida biológico (Bacillus thuringiensis) para controle da lagarta do cartucho (Spodoptera frugiperda). A amostragem de raízes e solo foi feita na profundidade de 0 a 20 cm no estádio R3 (grão pastoso). Foi utilizado o delineamento em faixas de tratamento com dez repetições.  Os dados foram submetidos ao teste de normalidade de Shapiro-Wilk e as médias dos tratamentos comparadas pelo teste t de Student (P<0,05). Os resultados mostram maiores índices de colonização micorrízica e concentração de glomalina no solo no cultivo alternativo com milho variedade, comparado ao cultivo convencional com cultivar transgênico. Em relação ao número de esporos viáveis não houve diferença significativa entre os tratamentos. O milho variedade, submetido ao manejo alternativo, proporcionou melhores condições para o desenvolvimento dos fungos micorrízicos, indicando ser esta a melhor opção para este simbionte.

The aim of this study was to assess the bromatological quality and the content of essential amino acids in maize grains produced using two different cropping systems: organic and conventional. The experimental area was four hectares, divided into two hectares per system. In the conventional management, agrochemicals from conventional maize production were used. In the organic management, inputs permitted by the current Brazilian legislation on organic production were used. For each system, 10 plots of 9 m² each were established, from which experimental samples were harvested. A significant difference was found in the bromatological quality of maize grains. The conventional management provided greater crude protein content. Significant changes were also found in the following amino acids: methionine, threonine, arginine, isoleucine, leucine, valine, histidine, and phenylalanine, which showed lower levels in the organic management. The results confirm the need to determine food composition before diet formulation, since using preestablished food compositions probably leads to differences between what was formulated and what was actually given to poultry. The type of management influenced the quality of maize grains. The management of plant nutrition in the organic system should be refined to adequately supply nitrogen, thus improving bromatological and amino acid quality of the grains.

10 cm depth there were significantly differences between 50 to 140 DAS to bulk density (1.23 to 1.41 g.cm-3), mean geometric diameter (1.58 to 1.29 mm), total porosity (55 to 49%) and macro porosity (24 to 13%). The grain yields were: 5.0, 4.1 and 4.8 t.ha-1 to ECSI, CSNI and CCS treatments, respectively.

-The aim of this study was to propose a mixture of micronutrients with amino acid-based foliar fertilizer as an alternative to calda viçosa for application in organic agriculture. The study was conducted in two simultaneous trials in an experimental field in Ipeúna, SP, Brazil. The test plant was carioca type dry edible bean cv. Pérola. The treatments in trial 1 were: Control 1 = water; FA = JK® amino acid-based foliar fertilizer; and FA+Mi = FA + CuSO 4 + ZnSO 4 + MnSO 4 + H 3 BO 3 . In trial 2, the FA treatment was substituted by calda viçosa (CVi). The treatments were through spray application three times. Dry edible bean leaves were sampled for determination of macronutrient and micronutrient concentrations. Platings of the application rates used in the treatments were performed in the laboratory in a mixture with Bacillus thuringiensis and with Beauveria bassiana to compare the degree of compatibility by means of colony forming units (CFU). The FA+Mi and CVi treatments raised the concentrations of Zn, Cu, and Mn in the leaves. The FA+Mi was compatible, the FA was a stimulant, and the CVi was noxious to B. bassiana and to B. thuringiensis when integrated in the spray mixture.Keywords: Bacillus thuringiensis, Beauveria bassiana, copper, manganese, zinc. FERTILIZANTE A BASE DE AMINOÁCIDOS COMO