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Trocas gasosas em diferentes acessos de umbuzeiro

2024-12-26T12:43:59Z

Título: Trocas gasosas em diferentes acessos de umbuzeiro Abstract: The objective of this work was to evaluate the gas exchange in umbuzeiro accessions. The experiment was carried out in a completely randomized design in a 5×7×2 scheme (accessions BRS-68, EPAMIG-05, BGU-61, BGU-75 and BGU-50 × evaluation times × reading time – 8h and 14h) in plots subdivided in time, with three repetitions. The accession of umbuzeiro BRS68 presents higher carboxylation and photochemical efficiency, and association between carboxylation efficiency and net photosynthesis. Umbuzeiro limits transpiration by reducing stomatal conductance under high vapor pressure deficit. In umbuzeiro, there is a limitation of the efficiency of carboxylation and photosynthesis due to high temperatures, a limitation of transpiration due to a decrease in stomatal conductance and a decrease in the quantum efficiency of photosynthesis due to the quality of radiation. The association between transpiration and stomatal conductance is positive and of high magnitude. The association between internal CO2 concentration and intrinsic efficiency of water use is significant negative and of high magnitude. Tipo: Dissertação

QIrriga - aplicativo para manejo de irrigação via clima

2024-12-19T14:12:53Z

Título: QIrriga - aplicativo para manejo de irrigação via clima Abstract: The unregulated use of water becomes an unsustainable practice, generating several problems, which can be caused due to the inappropriate use of the resource. The use of technologies that enable the rational use of water resources in irrigated agriculture is of fundamental importance for productive and environmental sustainability. The objective of this work was to develop a mobile application for climate-based irrigation management. The QIrriga was developed in Java programming language, using Android Studio, which is an integrated development environment, and enables you to obtain the irrigation time for micro-sprinkler, drip, and conventional sprinkler irrigation systems, and the percentimeter value for center pivot, by entering location, meteorological, irrigation system and crop data, so that the user can manage irrigation in a more efficient and sustainable way. The application also has a user-friendly and easy-to-understand interface. To validate the process and use of the application, the results of the application were compared to values calculated through passages in the literature, with the aid of electronic spreadsheets. Tipo: Dissertação

Produção forrageira em sistemas integrados no semiárido

2024-12-19T13:25:34Z

Título: Produção forrageira em sistemas integrados no semiárido Abstract: The overall objective of this study was to evaluate the agronomic characteristics of forage sorghum established through crop-livestock integration with pigeon pea and Massai grass or Paiaguás grass, as well as to assess the productive performance of intercropped and sole-cropped cultures under semi-arid climate conditions in two study cycles. The cultivars used in the experiment were forage sorghum BRS658, pigeon pea Mandarim, Massai grass BRS, and Paiaguás grass BRS. The experimental design used was randomized blocks, in a 2x2x2 factorial scheme, with two cultivation methods, sole cropping, and intercropping, with the combinations of sorghum, pigeon pea, and Massai grass or Paiaguás grass, and four replications. The experimental period was from November 2020 to May 2021. The evaluations were carried out in two production cycles, the first at 120 days post-planting and the second at 70 days after the harvest of the first cycle. Plant height, natural matter productivity, dry matter productivity, dry matter content, botanical composition, and leaf-to stem ratio were assessed. There was a reduction in the dry matter productivity of sorghum when intercropped with Massai grass and/or pigeon pea in the first cycle. The total natural biomass productivity and total dry biomass productivity of the evaluated forage species were affected by the intercropping systems. The botanical composition of individual species was lower in the intercropped system compared to sole cropping; however, the intercropped system promoted an increase in forage diversity in treatments with integrated species. Massai grass showed the highest leaf-to-stem ratio (F:C), while sorghum exhibited the lowest F:C ratio among the evaluated species. Tipo: Dissertação

Palma forrageira ‘gigante’ em arranjo mecanizável, diferentes densidades e tipos de cortes na colheita

2024-12-18T14:57:43Z

Título: Palma forrageira ‘gigante’ em arranjo mecanizável, diferentes densidades e tipos de cortes na colheita Abstract: The forage cactus (Opuntia fícus-indica (L.) Mill), cv. Giant belongs to the cactaceae family, and has important characteristics for the semiarid climate region. Forage cactus is a perennial crop and the management adopted during the productive cycle can influence the productive response of plants. The objective of this work was to evaluate the productivity and morphometric characteristics of the forage cactus submitted to different plant densities and cut types during two harvest cycles. The experiment was installed at the Federal Institute of Education, Science and Technology of Bahia, Campus Guanambi, in a dystrophic Yellow Red Latosol. The experiment was a randomized block design (RBD) in a split-split-plot (6 x 3 x 2). The plot consisted of six densities: 22,857; 34,286; 51,428; 62,857; 80,000 and 95,000 plants ha-1 ; the split-plot was constituted by three types of cuts: preserving three, two and one primary cladodes per plant; and the split-split-plot was constituted by two harvest cycles: corresponding to the year 2017 and 2018. In total, there were 36 treatments, with three replications, totaling 108 experimental units. The data were submitted to analysis of variance to verify the significance and, when found, these were compared by Tukey test (P <0.05) for cut types and harvest cycle, and regression analysis for plant densities. There was a significant interaction between density and cut type, also for density and harvest year. It observed a significant difference for cut types and year of harvest. The increase in planting density increases the cladode area index and decreases the total cladode area and the cladode number by plants. Cutting that preserves three primary cladodes per plant at harvest provides greater productivity. Years with higher rainfall provide higher cladode number, total cladode area, plant height and cladode area index. Tipo: Dissertação