Nathan Mickael de Bessa Cunha

Plant growth regulation has proven to be a promising strategy to optimize soybean yield performance, especially under varying planting densities. This study aimed to evaluate the effects of post-emergence herbicide application compared to mechanical pruning on the development and yield of soybean grown under two plant population densities. The experiment was carried out under field conditions during the 2021/2022 growing season on a farm located in Ipameri, Goiás, Brazil. A randomized block design was used in a 5 × 5 × 2 factorial arrangement with four replications. Treatments consisted of five intact technology soybean cultivars (providing pest protection and herbicide tolerance—RR2 PRO® or Xtend® 2) with indeterminate growth habit (Tormenta CE, M8372 Ipro, ST 797 Ipro, M7739 Ipro, and BMX Bônus Ipro), combined with five pruning alternatives: the application of three growth-regulating herbicides (2,4-D; imazethapyr; and lactofen), a mechanical pruning treatment, and a control without pruning. Each cultivar was evaluated under two plant population densities (recommended and 30% higher). Agronomic traits were assessed at harvest. Data were subjected to analysis of variance, and means were compared using Tukey’s test at a 5% significance level. The results showed that lactofen application (400 mL ha ⁻¹ ) significantly improved grain yield and controlled plant height across all cultivars and planting densities. For instance, the Tormenta CE cultivar under mechanical pruning yielded 6.092,67 kg ha ⁻¹ at the recommended population and 5.400,00 kg ha ⁻¹ at the higher density. In contrast, imazethapyr reduced yield, and the application of 2,4-D resulted in plant death in all cultivars except Tormenta CE. Mechanical pruning was less effective in controlling plant growth, especially at higher densities. These findings suggest that lactofen is a viable strategy for modulating soybean growth, improving productivity, and facilitating crop management, regardless of cultivar or planting density.

The common bean relies on biological nitrogen fixation to meet part of its nitrogen requirements. This study aimed to evaluate the effect of reinoculation with Rhizobium tropici, alone or combined with Azospirillum brasilense, at different phenological stages. The experiments were conducted in the winter of 2023 and the rainy season of 2023/24, and significant differences were observed between seasons, mainly due to temperature and water stress, which impacted nodulation, plant growth and grain yield. However, appropriate water management mitigated these limitations, allowing reinoculation combined with co-inoculation at the V4 stage to improve nodular and morphophysiological traits, ensuring adequate nutrition through biological nitrogen fixation. This strategy promoted nodulation and plant development, resulting in an 8.5% increase in yield compared to nitrogen fertilization (80 kg ha⁻¹), reaching 2197.87 kg ha⁻¹. These results suggest that reinoculation with co-inoculation at the V4 stage can enhance biological nitrogen fixation, reduce dependence on synthetic fertilizers and serve as a sustainable and economically viable alternative.

This study evaluates the impact of Rhizobium tropici reinoculation and Azospirillum brasilense co-inoculation at different growth stages on the physiological quality of common bean seeds. A randomized block design was used, assessing germination, vigor, electrical conductivity, seedling length, and dry mass. Treatments T7 (co-inoculation R. tropici + A. brasilense at R5) showed the highest germination rates, indicating enhanced seed viability. The accelerated aging test revealed that T7 exhibited greater resistance to stress, presenting greater seedling vigor, whereas T10 and T11 were more susceptible. The electrical conductivity results remained stable across treatments, suggesting that cell membrane integrity was not significantly compromised. Seedling length and dry mass did not present significant variations, reinforcing the idea that early germination and vigor are primary indicators of seed quality. Canonical discriminant analysis and MANOVA confirmed significant treatment differences, highlighting the influence of inoculation strategies on seed physiology. Overall, co-inoculation with Rhizobium tropici and Azospirillum brasilense (particularly in T7) demonstrated potential to improve seed quality at lower cost, offering sustainable alternatives for optimizing agricultural production.

Jambu (Acmella oleracea), also known as Pará cress, is a plant widely used in cuisine and traditional medicine, standing out for causing a tingling sensation in the mouth due to the presence of the compound spilanthol. This research aimed to analyze the effects of inlet temperature on the drying process of Jambu leaf extract using a spray dryer. The experiment was conducted at temperatures of 110°C and 140°C, respectively. The results indicated that the higher temperature (140°C) provided a greater powder yield (40.10%) compared to 110°C (30.94%). Water activity remained below 0.3 in both conditions, indicating microbiological stability. The color of the powder showed no significant variations, maintaining favorable visual characteristics. The bulk density was lower at 140°C (0.22 g.cm-³) compared to 110°C (0.39 g.cm-³). Morphological analysis revealed that higher temperature resulted in more spherical and regular particles.

The use of bacterial inoculants has great potential to improve yield and sustainability; however, application forms still face bottlenecks, such as the standardization of methods and compatibility with different varieties of bean. The objective of this study was to evaluate the growth and yield of bean cultivars subjected to inoculation and co-inoculation with rhizobacteria. The experiments were carried out using a randomized block design, with three replicates. Treatments consisted of four bean cvs. (BRS FC 402, BRS Estilo, BRS Pitanga, and BRS Esteio), subjected to inoculation with Rhizobium and co-inoculation with Azospirillum, applied to seed or soil, plus eight additional treatments with a mineral N source and its absence (control) for each cvs. The use of co-inoculation of R. tropici with A. brasilense promoted an improvement in the morphophysiological and agronomic characteristics, attributed to the ability of rhizobial bacteria to supply nitrogen to plants and to Azospirillum through hormonal action. The cvs. BRS Estilo and BRS Esteio had the best grain yields when co-inoculated via soil, 2049 and 1831 kg ha⁻¹, respectively. Co-inoculation with R. tropici + A. brasilense applied to the soil can be used as an exclusive source of N supply in the bean, contributing to lower costs and more sustainable production.

A pera é um fruto que possui alta densidade de nutrientes, rica em carboidratos, fibras, minerais e antioxidantes e, por isso, os níveis de perdas pós colheita destes frutos são elevados. Dessa forma, algumas técnicas são empregadas para prolongar sua vida útil, como a radiação ultravioleta C (UV-C), técnica tecnológica e sustentável. Deste modo, o objetivo da pesquisa foi avaliar o efeito de radiação UV-C na conservação pós-colheita de peras ‘Williams’. Foi utilizado um delineamento inteiramente casualizado (DIC), em esquema fatorial duplo 5x8 (doses de radiação UV-C x dias de análise), com 4 repetições com 1 fruto cada. O primeiro fator foi composto por cinco doses obtidas pela exposição à fonte de radiação UV-C: controle - sem exposição à radiação UV-C (0,0 kJ m-2); 0,5; 1,0; 2,0 e 4,0 kJ m-2. O segundo fator foi dias de análise (0, 4, 8, 12, 16, 20, 24 e 28 dias). Os frutos foram avaliados durante oito dias de análise, a cada quatro dias, quanto aos parâmetros pós-colheita: Perda de Massa; Sólidos Solúveis; Firmeza; Coloração; Acidez Titulável (AT) e Índice de Maturação (IM). As doses de radiação 1,0 e 2,0 kJ m-2 foram as mais eficazes na conservação do fruto por maior tempo. Em relação ao tempo de armazenamento, as peras se mantiveram com características adequadas para a comercialização durante todo o período analisado, principalmente pela firmeza da casca e índice de maturação, parâmetros indicativos de conservação das características pós-colheita.

Biological nitrogen fixation (BNF) can provide the necessary nitrogen for bean crops; however, for this to occur, important limitations involving the inoculant application technology need to be overcome.The use of co-inoculation is a management technique used to obtain benefits and increase the potential of N₂ fixation from the association between bacteria from the rhizobia group, such as R. tropici, and bacteria that promote plant growth, such as A. brasilense, in association with the addition of nutrients that allow greater efficiency of bacteria fixing atmospheric N₂. This study aimed to evaluate the bean response to the reinoculation of R. tropici in co-inoculation with A. brasilense in a mixture with the micronutrients Co/Mo, in the winter season of 2021, in Anápolis-GO, Brazil. A randomized block design was used, with four replications, and the following treatments (TRs) were studied: TR1—reinoculation with R. tropici; TR2—reinoculation with co-inoculation of R. tropici + A. brasilense; TR3—reinoculation of R. tropici + Mo/Co micronutrients; TR4—reinoculation with co-inoculation R. tropici + A. brasilense + Mo/Co micronutrients; TR5—inoculation via seed, without reinoculation; TR6—mineral N fertilization in the sowing furrow and topdressing; TR7—control, without any N source. At stage R6, nodulation characteristics (number and dry mass of nodules) and the morphophysiological parameters of the plants (main root length, root dry mass, plant height, shoot dry mass, leaf area, and leaf N content in the shoot) were evaluated. At harvest, the final plant stand and components (number of pods per plant, number of grains per pod, and average weight of one hundred grains) were determined, in addition to grain yield. It was concluded that inoculation followed by reinoculation in topdressing with R. tropici in co-inoculation with A. brasilense plus Mo/Co, compared to mineral nitrogen fertilization, improves the efficiency of the nodulation process and the morphophysiological characteristics of the common bean crop. Seed inoculation and topdressing application with R. tropici, associated with co-inoculation with A. brasilense + Mo and Co, have the potential to completely replace mineral nitrogen fertilization in common bean crops.

O abacate (Persea americana M.), fruta oleaginosa climatérica, possui considerável qualidade nutritiva, no entanto, prolongar sua vida útil é um dos fatores cruciais para aumentar a sua comercialização. O presente estudo teve como objetivo avaliar os efeitos da aplicação pós-colheita de cloreto de cálcio em abacate “Breda” armazenado sob refrigeração, e avaliar as características de qualidade dos frutos durante o armazenamento refrigerado. Foi utilizado um delineamento inteiramente casualizado (DIC), com 4 tratamentos de cloreto de cálcio (CaCl2), sendo o controle somente com água destilada (T1) e o restante com 1% (p/v) (T2), 2% (p/v) (T3) e 3% (p/v) de CaCl2 (T4). Os frutos foram armazenados à 10 ± 0,18°C com umidade relativa de 60 ± 4,73%. As variáveis analisadas foram submetidas à análise de variância (p≤0,05) e, quando significativas, as médias foram avaliadas por regressão. Os resultados mostraram que a utilização de 3,0% CaCl2 proporcionou aumento nos valores de luminosidade e croma nos frutos. No entanto, essa melhoria da aparência foi acompanhada por aumento na perda de massa (7,950 e 8,99%), sendo proporcional à concentração de cloreto de cálcio aplicada. Além disso, em relação as doses empregadas, observou-se redução da acidez com o aumento da concentração de CaCl2, com 0,115% (1% CaCl2) a 0,103% (3% CaCl2). O pH e a firmeza também foram afetadas ao longo do armazenamento. Essas descobertas ampliam o entendimento do manejo pós-colheita do abacate, oferecendo insights importantes para produtores e profissionais da indústria, com o objetivo de aprimorar a qualidade e a comercialização dessa fruta climatérica.