ResumoO objetivo deste trabalho foi avaliar o dano causado por Bipolaris maydis (helmintosporiose) na quantidade e qualidade da produção do capim Tanzânia. Plantas de capim Tanzânia foram cultivadas em vasos de tubos de PVC (50 cm de altura x 15 cm de diâmetro) contendo mistura solo/areia (3:1). As plantas foram inoculadas com suspensões de esporos do patógeno com diferentes concentrações (10 2 , 10 4 e 10 6 conídios/mL), visando obter gradiente de severidade de manchas foliares. Foram realizadas avaliações semanais da severidade e do número de perfilhos. Após quatro semanas avaliou-se o peso da matéria fresca de folhas (MF), porcentagem de matéria seca (PMS), de proteína bruta (PB), de fibra em detergente neutro (FDN) e de fibra em detergente ácido (FDA). A doença reduziu significativamente o perfilhamento e MF a partir da segunda avaliação (P < 0,05). Não houve correlação significativa entre as variáveis PMS, FDA e área abaixo da curva de progresso da doença (AACPD). No entanto, houve correlação positiva (P < 0,01) e negativa (P <0 ,05) entre PB e FDN, respectivamente, com a AACPD, como possível resultado da atividade do patógeno. Estes resultados indicam que B. maydis inibe o desenvolvimento do capim Tanzânia e promove alteração na qualidade da forragem. Palavras-chave: Mancha foliar, helmintosporiose, função de dano AbstractThe aim of this research was to evaluate the damage caused by Bipolaris maydis in the quantity and quality of the Tanzania grass production. Tanzania grass plants were cultivated in pots of PVC tubes (50 cm of height x 15 cm of diameter) containing a mixture of soil and sand (3:1). The plants were inoculated with spore pathogen suspension containing 10 2 , 10 4 and 10 6 conidia/mL to obtain different levels of disease. Severity and number of tillers were evaluated weekly. After four weeks, it were evaluated the weight of the fresh matter of leaves (FM), percentage of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF). The disease reduced significantly the plant tillering and FM after the second evaluation (P < 0.05). There was no significant correlation among the variables DM, ADF, and the area under disease progress curve (AUDPC). However, there were positive (P < 0.01) and negative (P < 0.05) correlations among CP and NDF, respectively, with AUDPC, as possible result of the activity of the pathogen. These results showed that B. maydis inhibits the development of the Tanzania grass and promotes alteration in the quality of the forage.
The briquette is considered a solid biofuel, made from the compaction of lignocellulosic residues used for the generation of energy. This work aimed to study the production of briquettes from mixtures of Urban Pruning Waste (RPU) (pruning of leaves and thin branches of trees), glycerin and cassava bagasse (Manihot esculenta). Samples of RPU, cassava bagasse and glycerol were mixed to yield treatments T1 (100% RPU), T2 (92% RPU and 8% cassava bagasse), T3 (97% RPU and 3% glycerin), T4 (89% RPU, 8% cassava bagasse and 3% Glycerin), T5 (94.5% RPU, 4% cassava bagasse and 1.5% glycerin) and T6 (control). Following this step, physical, chemical and energetic analyses (moisture content, volatile material content, fixed carbon and ash content, superior, inferior and useful calorific value, mechanical resistance, apparent and energetic density) of the briquettes were carried out. Treatment T2 had a lower fixed carbon value and volatile content, as well as higher ash content and mechanical strength. The percentages of carbon, hydrogen and nitrogen did not differ statistically between the treatments. The higher, lower and useful heating values were higher in treatment T3. The results showed that treatments T1, T2 and T3 were more efficient, producing briquettes with properties that meet market specifications, besides presenting great energetic potential, being good substitutes for firewood.
The objective of this research was to evaluate the agronomic performance and productivity of sixteen genotypes of Chenopodium quinoa cultivated in agroecological and conventional production systems. The evaluations were carried out, based on agronomic characteristics and yields of sixteen C. quinoa genotypes, grown in two simultaneous experiments, in an agroecological production and a conventional production system carried out at the town of Entre Rios do Oeste, Paraná, Brazil in the harvest 2015/16. Each experiment was composed of three replicates, following the randomized block design. Number of plants in flowering, number of plants per linear meter, height of insertion of the first panicle, number of days for maturation and productivity were the parameters evaluated. The data were submitted to statistical analysis with the aid of the GENES computational application. Genotype Q13-24 showed a more suitable production for the conventional production system. While the genotype Q13-01, presented the increase of productivity, being more indicated to the system of agroecological production. The characteristics height of plant flowers (HPF) and height of insertion of the first panicle (HIP) had higher values when the plants were cultivated in a conventional system. The number of plants per linear meter (NPLM) was higher in the agroecological crop, when compared to conventional cultivation. The same quinoa genotype can behave differently depending on the area management, being a productivity and the genotype cycle depends on the production system and the genotype used.
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.
Aims: The objective was to carry the phytosociological survey of spontaneous plants in the agroecological maize crop cultivated with intercalar cover plants in the summer and fall/winter harvest. Study Design: The experimental design used was of randomized blocks with subdivided plots in the time 4x2x2, with 5 replicates. Place and Duration of Study: The experiment was conducted in a farm, located in Missal – PR, managed in agroecological system since 2009. Methodology: The crop modalities used were maize + pigeon pea, maize + showy rattlepod, maize + jack bean and monoculture (control), being evaluated during summer and fall/winter seasons, at 30 and 70 days after emergence. Frequency, abundance, and density of plants per linear meter and the importance value index (IVI) were determined in a 1 m² area. Results: The specie Commelina benghalensis L. and Leonorus sibiricus L, were the plants with the highest IVI for the crop modalities maize + pigeon pea and maize + showy rattlepod. Conclusion: The cultivation of maize with cover crops, mainly showy rattlepod, may be a recommended management to reduce spontaneous plants in maize in the agroecological system. Aims: The objective was to carry the phytosociological survey of spontaneous plants in the agroecological maize crop cultivated with intercalar cover plants in the summer and fall/winter harvest. Study Design: The experimental design used was of randomized blocks with subdivided plots in the time 4x2x2, with 5 replicates. Place and Duration of Study: The experiment was conducted in a farm, located in Missal – PR, managed in agroecological system since 2009. Methodology: The crop modalities used were maize + pigeon pea, maize + showy rattlepod, maize + jack bean and monoculture (control), being evaluated during summer and fall/winter seasons, at 30 and 70 days after emergence. Frequency, abundance, and density of plants per linear meter and the importance value index (IVI) were determined in a 1 m² area. Results: The specie Commelina benghalensis L. and Leonorus sibiricus L, were the plants with the highest IVI for the crop modalities maize + pigeon pea and maize + showy rattlepod. Conclusion: The cultivation of maize with cover crops, mainly showy rattlepod, may be a recommended management to reduce spontaneous plants in maize in the agroecological system.
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