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dissertação
Aplicação foliar de iodo na mitigação dos efeitos do déficit hídrico em plantas de soja
(Universidade Federal de Lavras, 2026-07-18) Bonézio, Hugo; Silva, Lucas de Ávila; https://orcid.org/0000-0003-4058-2167; Nascimento, Vitor de Laia; https://orcid.org/0000-0001-5276-2638; Martins, Fábio Aurélio Dias; https://orcid.org/0000-0002-6776-617; Marchiori, Paulo Eduardo Ribeiro; https://orcid.org/0000-0001-9767-9336
Soybean (Glycine max (L.) Merrill) is one of the world's most important agricultural crops, widely used for human and animal nutrition and biofuel production. In Brazil, the main challenge to increasing its productivity is water deficit, which compromises essential physiological and biochemical processes, including photosynthesis, cell growth, and redox balance. Iodine is a non essential yet beneficial element for plants, possessing antioxidant and regulatory potential; thus, its application to cultivated plants can certainly offer advantages. Given this context, the objective of this study was to evaluate the capacity of iodine to mitigate the effects of water deficit in soybean plants. For the experiment, a completely randomized design was used. Two water regimes (80% of field capacity [control] and 50% of field capacity [water deficit]) and two iodine sources—potassium iodide (KI) and potassium iodate (KIO₃)—were employed, with two application rates (5 and 10 mM) for each source. Two experiments were conducted in which the iodine sources were tested separately, combining the application rates and water regimes. Physiological and morphological parameters were analyzed during the water deficit period and after recovery. Morphophysiological, seed yield, gas exchange, and biochemical parameters, as well as leaf water potential (midday and predawn), were measured throughout the crop cycle. The results indicate that foliar application of potassium iodide (KI) yielded less consistent responses regarding soybean plant tolerance to and recovery from water deficit. Conversely, the application of potassium iodate (KIO₃) produced more pronounced effects—particularly at the 10 mM concentration—favoring the maintenance of crop growth and yield, as well as better physiological recovery following rehydration.
Artigo
Breeding for drought tolerance in perennial ryegrass (Lolium perenne L.) and tall fescue (Lolium arundinaceum [Schreb.] Darbysh.) by exploring genotype by environment by management interactions
(2023) Fernandes Filho, Claudio C.; Murad Leite Andrade, Mario H.; Rodrigues Nunes, Jose A.; Wipff, Josephv; Hignight, Debra L.; Rios, Esteban F.; Kenworthy, Kevin; Hignight, Kenneth
Background: Drought‐tolerant turfgrass cultivars are becoming more important each year as landscape irrigation practices are becoming more restrictive. Methods: In this study, we quantified the level of drought tolerance (DT) in perennial ryegrass and tall fescue genotypes across years under different mowing (MH) and fertility (FL) rates. A total of 48 ryegrass and 38 tall fescue genotypes were planted in 2011 at NexGen, Albany, OR. The trial was divided into three subtrials: (i) DT; (ii) MH and DT; and (iii) FL and DT. Results: The results showed that there was significant genetic variance for most of the traits in both species. The genotype × year interaction was predominantly simple, indicating small changes in genotype ranking for both species. Lower MH improved DT in perennial ryegrass, whereas higher MH resulted in greater DT in tall fescue. For both species, higher MH improved the population mean for turf quality. Higher FL inputs led to higher turf quality for both species, but it did not affect the DT response. Conclusions: Using a selection index, six genotypes for perennial ryegrass and four for tall fescue were selected.
Artigo
Bolsa Família e (in)segurança alimentar em município mineiro: estudo com crianças até sete anos
(2023-12-13) Alvarenga, Ana Pereira; Bernardes, Milena Serenini; Verissimo, Marina de Oliveira; Maís, Laís Amaral; Bernardes, Renan Serenini; Teixeira, Lílian Gonçalves; Longo-Silva, Giovana; Toloni, Maysa Helena de Aguiar
The Bolsa Família Program has been the objective of studies that show the impact of reducing extreme poverty and reducing food and nutritional inse- curity (FNI). Objective: investigate the prevalence of FNI and factors associated among families with children under seven years old participating in the Bolsa Família Program, residing in a municipality in the south of the state of Minas Gerais. Methods: Quantitative cross-sectional study conducted with 145 families and 206 children under seven years old were evaluated. Results: The prevalence of FNI was 77.9%, and 15.9% of severe insecurity. The association between FNI and family income (p = 0.024), food after receiving the benefit (p = 0.006), bean consumption (p = 0.016) and snack foods (p = 0.006) were found among children of two to seven years. In addition, iron deficiency anemia was associated with the introduction of stuffed crackers (p = 0.023), packet chips (p = 0.044) and petit suisse cheese (p = 0.014) before the age of two. Conclusion: Therefore, it is expected that this research contributes to the generation of scientific evidence that will be used in decision making to improve management efficiency by redefining priorities and qualification of professionals involved in the program.
Artigo
Blending Controlled-Release and Urease-Inhibitor Technologies as Innovative Solutions to Reduce Ammonia Emissions in Coffee Environments
(2023-09-30) Freitas, Tainah; Oliveira, Damiany Pádua; Dutra, Mateus Portes; Zito, Pauliana Cristina; Reis, Estevam Antônio Chagas; Fernandes, Tales Jesus; Nunes, Ana Paula Pereira; Guimarães, Rubens José; Rabêlo, Flávio Henrique Silveira; Guelfi, Douglas
Enhanced efficiency fertilizers, such as urea treated with a urease inhibitor, controlled-release fertilizers (CRFs), and fertilizer blends, compose important strategies for improving efficiency in nitrogen (N) use by plants and mitigating ammonia (N-NH3) emissions. The physical mixture of fertilizers in blends can favor synchronization of N-release from the fertilizers and N-uptake by coffee plants and also dilute the costs of acquiring a pure CRF, making fertilizer blends more accessible to growers. To investigate this, a field experiment was conducted over two consecutive crop years with Coffea arabica with the aim of evaluating nitrogen fertilizer technologies at application rates ranging from 0 to 450 kg N ha−1. The fertilizers were characterized, and analyses were performed to quantify N-release from the fertilizers, ammonia volatilization, and nutritional and yield aspects of the coffee plant. The fertilizers used were urea (UCon), urea treated with N-(n-butyl) thiophosphoric-triamide (UNBPT), urea-coated with polymer of the E-Max technology (with 41%N (EMax41) or 43%N (EMax43)), and blends of UNBPT with E-Max (Blend41–Blend43). The cumulative N-release for EMax41 always remained below that for EMax43, just as occurred for Blend41 in relation to Blend43. Over the two crop years, the greatest volatilization of N-NH3 occurred with UCon (~25%) and the least with EMax41 (9%). The results indicate that the technologies mitigated the N-NH3 emissions in relation to UCon [EMax41 (63% mitigation) > Blend41 (43%) > EMax43 (32%) > UNBPT (28%) > Blend43 (19%)]. Crop management affects coffee yield. The yield increase went from 20% in the first crop year to 75% in the second, with better results from fertilizers containing CRF. We present information that can assist fertilizer producers and coffee growers, and, above all, we seek to contribute to environmental action for the reduction of agricultural NH3, clarifying potential strategies for mitigation of these emissions and strategies that generate advances in research on technologies for coffee growing.
Artigo
Biospeckle Laser On Clouds, a digital gateway aiming at collaborative research improvement
(2023-11-03) Braga, Roberto A.; Godinho, Robson P.
The Dynamic Laser Speckle (DLS) is a photonic phenomenon transformed into a technique to monitor tiny changes in many materials, particularly in biological ones (Biospeckle Laser – BSL). Its high sensitivity is key to monitor tiny changes in the tissues that can characterise biological features in medical and in agricultural samples. This work aimed to develop an environment at the world-wide-web to share raw data of BSL and to offer access to an interactively online analysis with tutorials. The gateway designed was implemented using PHP and JavaScript tools solving the challenges of managing data (images) and online interactive use. The result was an easy-to-use environment boosting the BSL research. The early results presented thousands of accesses and of more than one hundred different users from all around the world.