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This study aimed to analyze the influence of inoculation methods with Azospirillum brasilense in morphometric and nutritional parameters of the maize crop. Maize plants, hybrid Formula VT®, were grown under different forms of inoculation: absence of inoculation; seed inoculation; leaf inoculation; seed inoculation associated to leaf inoculation. In the phenological stages V8 and VT the parameters number of leaves, aerial height, root volume, stem diameter, besides the leaves, stem, sheath, root and total dry mass and the leaf content of nitrogen, phosphorus and potassium were determined. In the R6 stage, in addition to the previous evaluations the following parameters were determined: ear diameter and length, number of kernel rows, number of kernels per row, the reproductive structure and thousand grains dry mass, and total number of grains, besides the grain’s content of nitrogen, phosphorus, and potassium. The SPAD index from the leave’s apex, medial and basal thirds was measured fortnightly. The inoculation methods with A. brasilense had little influence in maize’s morphometric and nutritional parameters, also not influencing in production. Maize plants inoculated with A. brasilense, via seed and via seed associated to leaf spraying, positively stood out for the stem diameter, leaves dry mas, root volume, and for the nitrogen, phosphorus, and potassium leaf content.

The present work evaluated the influence of calcium silicate on the polygalacturonase enzyme activity, respiration, ethylene, and the physicochemical characteristics on the post-harvest quality of two tomato hybrids. The experimental design was of randomized blocks, with four repetitions in protected cultivation environment. The treatments were distributed in a 2 x 5 factorial scheme, corresponding to the hybrids (Ivety and Natalia) and five doses of calcium silicate (0, 150, 300, 450 and 600 kg ha-1), which were applied on the same day as the pots were filled. Evaluations were carried out on the fruits, namely: ethylene production, fruit respiration, firmness, number of loculus, polygalacturonase activity, total carotenoids, lycopene, phenolic compounds, soluble solids content, pH, titratable acidity and ascorbic acid content. The application of calcium silicate provided the reduction of ethylene production and fruit respiration. Natalia hybrid showed low polygalacturonase activity, this difference being due to genetic variabilityThe increase of calcium silicate doses provided the reduction of polygalacturonase enzyme concentration due to its constitution in the cell wall. The concentrations of lycopene, phenolic compounds, soluble solids, pH, titratable acidity and ascorbic acid in the fruits increased in response to the increasing doses of calcium silicate for 'Ivety'. Hybrids present distinct behaviors on the influence of the fertilization of tomatoes with calcium silicate, which can increase the post-harvest conservation and improve the physical-chemical characteristics of tomato fruits. El presente trabajo evaluó la influencia del silicato de cálcio sobre la atividade de la enzima poligalacturonasa, la resoiración, el etileno y las características físico-químicas em la calidad poscosecha de dos híbridos de tomate. El diseño experimental fue de bloques al azar, con cuatro repeticiones en cultivo protegido. Los tratamientos se distribuyeron em um esquema factorial 2 x 5, correspondientes a híbridos (Ivety y Natália) y cinco dosis de silicato cálcico (0, 150, 300, 450 y 600 kg ha-1), en el que se aplicaron en el mismo dia en que se llenaron los vasos. Se realizaron evaluaciones en los frutos, a saber: producción de etileno, respiración del fruto, firmeza, número de lóculos, actividad poligalacturonasa, carotenoides totales, licopeno, compuestos fenólicos, contenido de sólidos solubles, pH, acidez titulable y contenido de ácido ascórbico. La aplicación de silicato de cálcio proporcionó una reducción en la producción de etileno y la respiración de la fruta. El híbrido de Natália mostró una baja actividad poligalacturonasa, esta diferencia se debe a la variabilidade genética. El aumento de las dosis de silicato de calcio redujo la concentración de la enzima poligalacturonasa debido a su constitución en la pared celular. Las concentraciones de licopeno, compuestos fenólicos, sólidos solubles, pH, acidez titulable y ácido ascórbico de los frutos aumentaron en respuesta a las dosis crecientes de silicato de calcio para ‘Ivety’. Los híbridos exhiben diferentes comportamientos sobre la influencia de la festilización del tomate con silicato de calcio, lo que puede aumentar la conservación poscosecha y mejorar las características fisicoquímicas de los frutos del tomate. O presente trabalho avaliou-se a influência do silicato de cálcio sobre a atividade da enzima poligalacturonase, respiração, etileno e as características físico-químicos na qualidade pós-colheita de dois híbridos de tomate. O delineamento experimental foi de blocos casualizados, com quatro repetições em cultivo protegido. Os tratamentos foram distribuídos em esquema fatorial 2 x 5, correspondendo os híbridos (Ivety e Natália) e cinco doses de silicato de cálcio (0, 150, 300, 450 e 600 kg ha-1), nas quais estas foram aplicados no mesmo dia em que os vasos foram preenchidos. Realizou-se avaliações nos frutos, a saber: a produção de etileno, a respiração dos frutos, a firmeza, o número de lóculos, a atividade da poligalacturonase, os carotenóides totais, o licopeno, os compostos fenólicos, o teor de sólidos solúveis, o pH, a acidez titulável e o teor de ácido ascórbico. A aplicação de silicato de cálcio proporcionou a redução da produção de etileno e a respiração dos frutos. O hibrido Natália apresentou baixa atividade poligalacturonase, sendo esta diferença devido a variabilidade genética. O aumento das doses de silicato de cálcio proporcionou a redução da concentração da enzima poligalacturonase devido a sua constituição na parede celular. As concentrações de licopeno, compostos fenólicos, sólidos solúveis, pH, acidez titulável e ácido ascórbico dos frutos aumentaram em resposta às doses crescentes de silicato de cálcio para ‘Ivety’. Os híbridos apresentam comportamentos distintos sobre a influência da adubação do tomateiro com silicato de cálcio, podendo aumentar a conservação pós-colheita e melhorar as características físico-química de frutos do tomateiro.

Made available in DSpace on 2021-06-25T11:44:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-10-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The objective was to evaluate the effect of calcium silicate on the chlorophyll content and gas exchange of two tomato hybrids. The design used was in randomized blocks in a 2x5 factorial scheme, with four replications. The first factor was composed of two tomato hybrids: Ivety and Natalia, and the second factor was composed of five doses of calcium silicate (0, 150, 300, 450, and 600 kg ha(-1)), applied to the substrate before planting the seedlings. Gas exchange: net CO2 assimilation rate (A), leaf transpiration rate (E), stomatal conductance (gs), internal CO2 concentration (Ci), water-use efficiency (WUE), intrinsic efficiency water use (iWUE), and instant cathoxylation efficiency (ACi); SPAD index and the levels of chlorophylls a, b, and total were evaluated. The analyzes were performed in the stages of first flowering (17 days after transplanting - DAT), full flowering (58 DAT), and full fruiting (78 DAT). At 17 DAT, no difference was observed for gas exchange variables and photosynthetic pigments. The application of calcium silicate reduced gas exchange and photosynthetic pigments at 58 DAT. The hybrid Natalia had the highest A, WUE, iWUE, and ACi at 78 DAT. However, the hybrid Ivety in the same growth stage, in full fruiting, was superior only for the internal concentration of CO2 and SPAD index, with no difference for photosynthetic pigments. Univ Estadual Oeste Parana, Campus Marechal Candid Rondon, Marechal Candid Rondon, Parana, Brazil Corteva Agrisci, Palmas, Tocantins, Brazil Univ Estadual Paulista, Campus Botucatu, Botucatu, SP, Brazil Univ Estadual Paulista, Campus Botucatu, Botucatu, SP, Brazil

The objective was to evaluate the effect of the number of stems per plant in the gas exchange index, in the productivity and in the harvest precocity of Italian tomatoes. It was used a randomized block design in a factorial scheme 2 x 5, with four replicates. The first factor constituted of two cultivars of Italian tomatoes (“Giuliana” and “Tyna”) and the second by the number of stems per plant. At 78 days, it was evaluated the gas exchanges and production parameters of the cultivars. There was no statistical difference between the cultivars for the gas exchange indexes, however, the cultivar “Giuliana” was more productive. With relation to the conduction types, the highest values of the CO2 liquid assimilation rate were observed for the conduction type 3, however int did not result in meaningful results in productivity. The removal from the main stem retards the crop

The present study aimed to evaluate the productive performance of maize crop when seed inoculated with A. brasilense, associated with different foliar doses of magnesium in the crop vegetative stages. For this, two essays were conducted in field conditions, one located in Laranjeiras do Sul-PR and the other in Entre Rios do Oeste-PR. A randomized blocks scheme was used, with a 3 × 2 factorial, being the treatments with magnesium (Mg): magnesium sulphate; magnesium oxide and without magnesium, and the presence or absence of seed inoculation with A. brasilense. The magnesium sources were supplied via foliar at the V4 stage of the crop, using doses of 6 kg ha-1. Evaluations were carried at R1 determining the SPAD index and stem diameter and, at the end of the productive cycle, were evaluated production components and yield. In both sites no significant effects of foliar application with Mg were observed over the evaluated parameters. The A. brasilense inoculation provided an increase of 9.66% and 6.32% in stem diameter and of 6.8% and 6.24% in the SPAD index in Laranjeiras do Sul and Entre Rios do Oeste respectively, however, they did not increase production components and yield. It is concluded that the inoculation with A. brasilense increases of stem diameter values and SPAD index, in turn the foliar fertilization with different sources of magnesium do not interfere in the development and productivity of corn crop.

The aim was to evaluate the initial development of maize plants when submitted to mineral fertilization with magnesium sources in the presence or absence of seed inoculation with Azospirillum brasilense. To do so, was conducted an experiment in greenhouse. In the essay was adopted a randomized blocks design, in a factorial scheme 3 × 2, represented by the magnesium sources: magnesium sulfate (MgSO4), magnesium oxide (MgO) and control without Mg fertilization, in the presence or absence of inoculation with A. brasilense. The Mg sources were supplied with a dose of 30 kg ha-1, being homogenized in the substrate before sowing the crop. The analysis were carried out in the V4 stage, evaluating: basal stem diameter (BSD); relative chlorophyll content (SPAD index), leaf dry mass (LDM), stem + sheath blade dry mass (SSDM) and root dry mass (RDM). No differences were observed for the factors interaction and for the Mg sources. When considered the seed inoculation there was increases of 7.1%; 6.61%; 19.23%; 28.32%; and 15.17 %, for basal stem diameter, SPAD index, leaf dry mass, stem + sheath blade dry mass and roots, respectively. The inoculation of maize seeds with A. brasilense increases the initial development of maize plants and the SPAD index in greenhouse conditions in the V4, while the fertilization with the magnesium sources do not interfere in the maize development.

Growth promoting bacteria are a potential option for sustainable cultivation with lower costs, among them Burkholderia ambifaria, whose importance is mainly due to the endophytic root colonization capacity. The objective of this work was to evaluate the effect of the inoculation of growth promoting bacteria in corn plants, in vitro and in greenhouse, with different levels of nitrogen fertilization. The PIONEER® 30F53 YH maize genotype was inoculated with Burkholderia ambifaria, with 106 CFU per seed, in 12-liter polyethylene pots, filled with commercial substrate, prepared with the different nitrogen contents (N), resulting in treatments with different doses of fertilization, associated or not with bacterial inoculation. After 30 and 45 days, it was evaluated: growth promotion, epiphytic and endophytic population and nitrogen accumulation. In the in vitro experiment, inoculated seeds were cultured in test tubes containing culture medium with absence and presence of nitrogen, evaluated after 7 days. The data were submitted to analysis of variance and the means were compared by the Tukey test at 5% of probability and regression. Increased nitrogen doses in inoculated plants resulted in better morphological parameters at 45 days. In vitro bacterial inoculation, in vitro, influenced the accumulation of fresh weight of shoot, root growth and development of root hair. The endophytic potential and the accumulation of nitrogen were higher in the absence of nitrogen, but lower than the absence of bacteria and the presence of nitrogen.