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Navegando Dissertações por Assunto "Adubação nitrogenada"
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- DissertaçãoAcesso aberto (Open Access)Características agronômicas e qualidade fisiológica de sementes de trigo cultivado com doses de nitrogênio e de trinexapac-ethyl(Universidade Estadual do Norte do Paraná, 2020-12-11) Faria, Lucas Pinto de; Silva, Sérgio Ricardo; https://orcid.org/0000-0001-6951-8324; http://lattes.cnpq.br/8067599760812752; Silva, Sérgio Ricardo; https://orcid.org/0000-0001-6951-8324; http://lattes.cnpq.br/8067599760812752; Bazzo, José Henrique Bizzarri; https://orcid.org/0000-0001-9512-1611; http://lattes.cnpq.br/8466395433568127; Kolln, Oriel Tiago; https://orcid.org/0000-0002-8507-9808; http://lattes.cnpq.br/8041626078120100Wheat is used as a feedstock in several industrial products, being indispensable in the agro-industrial complex, whether in human or animal food. Nitrogen (N) fertilization is essential for wheat crop, as it increases grain yield and flour quality; however, it can increase the lodging of the crop. Trinexapac-ethyl is a hormonal product that reduces plant growth, and it is widely used to reduce the lodging of wheat crops. In this context, trinexapac-ethyl and N can be managed together, decreasing the possibility of crop lodging and increasing grain yield. In addition, environmental conditions and genetic materials are factors that strongly influence the response of plants to rates of N and trinexapac-ethyl. Finally, little information is available on the influence of N fertilization and plant-growth reducer on the physiological quality of seeds produced by wheat crop. The objective of this work was to evaluate the effects of rates of N and trinexapac-ethyl on plant agronomic characteristics and on physiological quality of wheat seeds. The experiment was carried out in two edaphoclimatic environments, Londrina and Ponta Grossa, in a randomized block design, with a 2 × 3 × 3 factorial arrangement, being two wheat genotypes (WT 15008 and WT 15025), three rates of N (0, 40, and 120 kg ha⁻¹) and three rates of the plant-growth reducer (0, 200, and 400 mL ha⁻¹ of the commercial product Moddus®). Agronomic characteristics related to wheat productivity (hectoliter weight, thousand grain weight, population density of fertile plants, plant height and lodging, and grain yield) and physiological quality of seeds (germination and vigor of seeds — by the cold and accelerated aging tests; length and dry matter of seedlings) were evaluated. The fertilization with the higher N rate caused negative effects on wheat crop, such as greater plant lodging in Londrina and reduced vigor of the produced seeds. The spraying of trinexapac-ethyl on wheat crop harmed the physiological quality of the seeds produced, reducing the length and dry matter of seedlings related to Londrina and Ponta Grossa. There was a wide diversity of interactions among the studied factors, which directly influenced the efficiencies of trinexapac-ethyl and N fertilization on the wheat crop. The genetic factor associated with the environmental conditions are the main determinants of the agronomic characteristics of the wheat plants, and of the physiological characteristics of the produced seeds, standing out from the effects of N fertilization and trinexapac-ethyl application.
- DissertaçãoAcesso aberto (Open Access)Eficiência de uso de nitrogênio por genótipos de cana-de-açúcar em ciclo de cana-planta(Universidade Estadual do Norte do Paraná, 2025) Dias Junior, Eduardo Siqueira; Rodrigues, Diego Resende; https://orcid.org/0000-0002-9495-8943; https://lattes.cnpq.br/9381400899886153; Kölln, Oriel Tiago; https://orcid.org/0000-0002-8507-9808; https://lattes.cnpq.br/8041626078120100; Kölln, Oriel Tiago; Franco, Henrique Coutinho; Silva, Sérgio Ricardo; Dário, Gustavo; Dário, Karina Aline Alves; https://lattes.cnpq.br/8041626078120100; https://lattes.cnpq.br/7632245413046227; https://lattes.cnpq.br/8067599760812752; https://lattes.cnpq.br/5682942731827088; https://lattes.cnpq.br/6915234182529881; https://orcid.org/0000-0002-8507-9808; https://orcid.org/0000-0002-1218-7533; https://orcid.org/0000-0001-6951-8324; https://orcid.org/0000-0002-8916-0224Nitrogen (N) is an essential macronutrient involved in fundamental physiological processes throughout the plant life cycle. Given its critical role, high-yield agricultural systems heavily depend on nitrogen fertilizers to ensure global food security. However, excessive N application is associated with significant environmental impacts, highlighting the need to improve nitrogen use efficiency (NUE). Sugarcane (Saccharum spp.), a key crop for bioenergy production and economic sustainability, exhibits high nitrogen demand, necessitating the evaluation of NUE in this system.This study aimed to assess NUE and nitrogen response in first-year sugarcane (plant cane) genotypes under field conditions. The experiment was carried out in a commercial sandy soil area of the Jacarezinho Mill, located in Jacarezinho, Paraná, Brazil. Sixteen sugarcane genotypes were arranged in a randomized block design with four replications. Each plot consisted of four 17-meter-long rows spaced 1.5 m apart, subdivided into two nitrogen treatments: high N (180 kg ha−1) and low N (9 kg ha−1). Planting was performed on August 10, 2023, using stalk segments provided by the mill. Nitrogen status in leaf +1 was evaluated at 180 days after planting (DAP). At harvest (July, 2024), biometric and yield parameters were assessed, including compartmentalized and total dry matter, stalk yield (TCH), and sugar yield (TAH). Additionally, technological analyses—POL (%), fiber (%), total recoverable sugar (TR) (kg t−1), and juice purity (PZA %) were performed in the mill’s laboratory. Nitrogen use efficiency (NUE) and responsiveness varied significantly among the 16 evaluated sugarcane genotypes. RB 127825 outstanding as the most nitrogen-efficient and responsive genotype, clustering with four others in the high-NUE quadrant. The other hand, CTC 9002 and IAC5094 were classified as inefficient and non-responsive, along with six additional genotypes. The remaining genotypes exhibited intermediate perfomed, distributed between inefficient-but-responsive and efficient-but-non-responsive groups. Genotypic differences in NUE were evident based on total dry matter (TDM) and stalk yield (TCH) indices. Clearilly, most variables showed no significant differences (p > 0.05) between high-N (180 kg ha−1) and low-N (9 kg ha−1) treatments within the same genotype, underscoring the predominant influence of genetic factors over nitrogen supply in determining NUE. This finding highlights the importance of genotype selection for optimizing field-level nitrogen management. Leaf nitrogen accumulation at 180 DAP did not differ significantly between nitrogen treatments. Similarly, technological parameters (POL, fiber, TRS, PZA) were unaffected by nitrogen fertilization. However, CTC 9001 and CTC 9002 consistently outperformed other genotypes in technological quality across both N conditions, irrespective of their NUE classification.
- DissertaçãoAcesso aberto (Open Access)Potencial forrageiro da Moringa oleifera Lam para ensilagem em diferentes adubações e alturas da planta no momento do corte(Universidade Estadual do Norte do Paraná, 2026) Mantovani, Tiago Marques; Porto, Petrônio Pinheiro; https://orcid.org/0000-0002-2999-7612; http://lattes.cnpq.br/1751366795715746; Porto, Petrônio Pinheiro; https://orcid.org/0000-0002-2999-7612; http://lattes.cnpq.br/1751366795715746; Bumbieris Júnior, Valter Harry; https://orcid.org/0000-0001-7255-4887; http://lattes.cnpq.br/0261912196782921; Silva, Marcelo Alves da; https://orcid.org/0000-0002-4299-1530; http://lattes.cnpq.br/3283906522734749This study evaluated the forage potential of Moringa oleifera Lam. for silage, analyzing the effects of different nitrogen fertilization sources and plant cutting heights on productivity and bromatological composition. A randomized complete block design was used, with four fertilization treatments (Control, horn and hoof meal – 100 kg N/ha, Urea 100 – 100 kg N/ha, and Urea 200 – 200 kg N/ha), three cutting heights (2.0, 3.0, and 4.0 m), and three replications, totaling 36 experimental plots. The evaluated variables included diameter at breast height (DBH), green matter yield (GMY), dry matter yield (DMY), and bromatological composition (dry matter – DM, crude protein – CP, neutral detergent fiber – NDF, ash, and total digestible nutrients – TDN). Cutting height directly influenced structural development and productivity. DBH increased linearly, with the control treatment ranging from 6.8 cm at 2.0 m to 19.2 cm at 4.0 m. Urea 100 promoted greater initial diameter (11.4 cm at 2.0 m), whereas at 4.0 m all treatments exceeded 19.0 cm. Increasing cutting height substantially enhanced biomass production, with GMY rising from 39.7 to 122.2 ton/ha under 200 kg N/ha, and DMY reaching 29.1 ton/ha with horn and hoof meal at 4.0 m. Dry matter content ranged from 19.0% to 25.3%, indicating the need for moisture adjustment for direct ensiling. Nutritional quality decreased with increasing cutting height, with crude protein exceeding 12.0% at 2.0 m and declining to approximately 5.0% at 4.0 m. NDF (60.0–62.8%) and TDN (51.2–55.6%) remained relatively stable. Nitrogen fertilization did not significantly affect chemical composition or productivity within each cutting height. In conclusion, cutting height is the main factor determining forage management in Moringa oleifera, with lower cuts favoring protein content and higher cuts maximizing biomass production, requiring moisture correction and protein supplementation strategies for silage use.