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Determinação da umidade de sementes pelos métodos da estufa a 105 e 130 oC
(Universidade Federal de Lavras, 2025-02-18) Raimunda Katiane Souza Lopes; José Marcio Rocha Faria; Anderson Cleiton José; Olívia Alvina Tonetti; Marília Shibata; Wilson Vicente Souza Pereira
Seeds are essential for agriculture and species conservation, and controlling their water content is crucial for maintaining their quality. This study compared the efficiency of the moisture determination method at 130 °C for different periods with the standard method at 105 °C for 24 hours. Additionally, the energy consumption of both procedures and the time required for the stabilization of water loss in seeds subjected to 105 °C were analyzed, considering different intervals relative to the standard. The experiment was conducted at the Forest Seed Laboratory of UFLA, using seeds from different species. The water content was determined with four replicates per treatment, following a completely randomized design. Statistical analysis included ANOVA and mean comparison using Dunnett’s test (α = 5%). Energy consumption was measured based on the incubator’s power and its effective operating time. Two independent experiments were conducted. In the first, seed moisture content was determined using two methods described in the Rules for Seed Analysis: the standard method (105 °C for 24 hours) and the 130 °C method, with drying times of 1, 2, 3, and 4 hours. In the second experiment, the drying time at 105 ± 3 °C/24h was extended to 6, 14, 30, 36, and 48 hours to identify the moment when the sample’s constant weight was reached. In both cases, the drying time count began after the incubator reached thermal stabilization. The results indicated that seed response varied depending on the species and method used. In the first experiment, the moisture content of banana-de-macaco and ipê-da-serra seeds did not statistically differ between the 130 °C method (1 to 4 hours) and the standard method at 105 °C for 24 hours. However, ipê-mirim and leucena seeds showed equal averages only in the first hour of drying at 130 °C compared to the standard method. For angico-amarelo and ingá-vera seeds, the averages were equal after 2 hours at 130 °C. Regarding energy consumption, the 130 °C treatments required less electricity than the standard method, with a reduction of up to 95.42% in the 1-hour treatment. Reducing drying time at higher temperatures increased energy efficiency and lowered operational costs. In the second experiment, evaluating different drying times at 105 °C, seeds such as tingui and aguaí showed statistically equal averages to the standard time after 6 hours. Other species required up to 48 hours for stabilization, demonstrating that the ideal time varies depending on the seed type. The results show that the 130 °C method can be a viable alternative for various species, reducing time and energy consumption without compromising analysis accuracy. Adjustments in drying time at 105 °C can also reduce the analysis time for some seeds, making laboratory processes more efficient.
Monitoramento da restauração ecológica de áreas atingidas por rejeito de minério de ferro na bacia do Rio Doce
(Universidade Federal de Lavras, 2025-02-24) Pedro Machado Neto; Soraya Alvarenga Botelho; Marcela de Castro Nunes Santos Terra; Israel Marinho Pereira; Natielle Gomes Cordeiro
The degradation caused by mining tailings is a serious environmental problem, with impacts on ecosystems, communities, and economies around the world. In Brazil, the Mariana (2015) and Brumadinho (2019) disasters in Minas Gerais illustrate the seriousness of these problems, causing environmental and human damage. Restoring the areas affected by the collapse of the Fundão dam in Mariana, MG, is essential to mitigate the damage and requires an integrated approach involving governments, industries, and communities. This incident has prompted several studies focused on the environmental and social recovery of these regions. This work seeks to evaluate the recovery of ecosystem functions in areas with iron ore tailings, monitored eight years after the Mariana accident, using ecological restoration indicators. The study, conducted in eight areas of the Doce River basin (Mariana and Barra Longa, MG), evaluated thirteen ecological indicators. The results show that restoration is a complex process. The tree stratum showed little improvement in richness and diversity, but the average height of the trees increased. Regeneration was limited by seed scarcity, disturbance, and competition with grasses, although some indicators improved locally. The canopy advanced, and ground cover varied, requiring management to reduce grasses and favor native herbaceous plants. The most relevant indicators were: number of individuals and number of species in the regenerating layer; number of individuals and average height of the tree layer; and percentage of ground cover by grasses. Recent restoration may not have been enough to differentiate between conserved and anthropized areas.
Avaliação do potencial de bactérias do solo na solubilização de potássio a partir de fonolito
(Universidade Federal de Lavras, 2024-07-30) Nzengele Nzambi; Ederson da Conceição Jesus; Jose Guilherme Guerra; Marcia Reed Rodrigues Coelho; Raul Castro Carriello Rosa
Potassium-solubilizing microorganisms have been used as bioinoculants to promote the growth of different crop species. Our study aimed to isolate, characterize, and test potassium-solubilizing bacteria from potassium rocks. The bacteria were isolated from tomato rhizosphere soil and a coastal rock formation in the state of Espírito Santo. Dilutions of 10⁻¹ to 10⁻⁹ were made and these were inoculated on plates using Aleksandrov and B & B culture media supplemented with phonolite-type potassium rock. Additionally, bacteria from the Johanna Döbereiner Resource Center were used as a source of potential solubilizing microorganisms. Organisms positive for K solubilization were grown in pure culture using DYGS medium and identified through analysis of the 16S rRNA gene sequences. Among the positive genera for solubilization are: Burkholderia, Paraburkholderia, Enterobacter, Ralstonia, Microbacterium, Nguyenibacter, Rhizobium, Bacillus, and Arvibacter. The BR 11366 strain of Paraburkholderia tropica and two isolates of Rhizobium sp. stood out in the liquid solubilization test. Unlike Rhizobium, the other microorganisms did not acidify the culture medium, indicating the action of a possible different mechanism for K solubilization. Inoculation with the different bacteria provided a greater accumulation of dry matter in the shoot of millet when cultivated at a low dose of K (40 kg ha⁻¹). The performance of plants inoculated under this condition was similar to that of plants under a high dose of K (400 kg ha⁻¹). Strains NZ11, from Arvibacter sp., and BR 3487, from P. tuberum, stood out as the best plant growth promoters. We conclude that the evaluated bacteria have the ability to promote millet growth under conditions of low K availability and have potential for future bioinoculants.
Aplicação da gamificação no ensino da temática alimentação sustentável para alunos do 6º ano do ensino fundamental
(2023-09-18) Silva, Cleunice Cristina da
The aim of this research was to investigate possible initiatives to welcome and support beginning teachers working in state schools in Minas Gerais, given that there are many reasons why professionals drop out and give up in their first years of teaching, such as the feeling of loneliness and not belonging, the lack of support associated with the precariousness and devaluation of their careers, and the challenges encountered during their initiation into teaching. A quantitative-qualitative, descriptive, and exploratory study was carried out using questionnaires sent to 46 Regional Teaching Superintendencies in Minas Gerais and interviews with 10 beginning teachers (9 contracted and 1 permanent) among those who answered the questionnaires. The study addressed the challenges faced by these teachers and explored how a collaborative learning community can contribute to the adaptation and development of these professionals during their professional integration. It also investigated the existence of strategies and initiatives for welcoming and providing emotional and professional support within the network, as well as the impact of the collaborative community on the professional success of novice teachers. It is hoped, therefore, that this research will effectively contribute to a change in professional reality, proposing the possibility of implementing a teaching-learning community from the perspective of professional development in an attempt to welcome and accompany teachers in their first years of teaching so that they can start their careers more lightly and with the prospect of professional continuity.
Avaliação dos remanescentes umbilicais e dos parâmetros físicos e achados hematológicos em potros neonatos da raça mangalarga marchador
(Universidade Federal de Lavras, 2025-03-10) Gil Fernando de Paula Júnior; Hugo Shisei Toma; Cláudia Dias Monteiro Toma; Antônio Carlos Cunha Lacreta Júnior; Matheus Camargos de Britto Rosa; Diego José Zanzarini Delfiol
The most challenging period for a newborn foal is the immediate postpartum period. The foal undergoes a transition to a highly challenging environment, putting its still immature immune system to the test. Early assessment of physical parameters, hematological findings, and ultrasound applied to the umbilical structures allows obtaining relevant information about the viability of the newborn. Umbilical affections are among the diseases that most affect neonatal foals under eight weeks of age, where the umbilical remnants act as an entry point for pathogens. This longitudinal study aimed to perform a clinical evaluation using ultrasound of the structures that make up the umbilical region of neonatal foals and describe the hematological values and vital physical parameters in healthy foals of the Mangalarga Marchador breed. To this end, 28 foals from properties specialized in breeding Mangalarga Marchador horses intended for activities in equestrian sports, work, and leisure were evaluated. This work will be presented in two chapters, the first will be a general introduction to the ultrasound examination of umbilical remnants, physical parameters, and hematological findings. The second will be presented in article format, with the first addressing the ultrasound examination and the second addressing hematological values and physical parameters.