José Ricardo Peixoto

Consumer interest in natural antioxidants has risen because their intake is linked to the prevention of chronic diseases. Blueberries (Vaccinium spp.)—rich in flavonoids, vitamin C and other bioactive compounds—are therefore being cultivated beyond temperate regions. In tropical areas, however, the lack of chilling hours may alter fruit physiology, and little is known about how pruning practices modulate quality under these conditions. The objective of this study was to quantify the effects of pruning types and seasons on the antioxidant activity, physical and chemical characteristics (TSS, TTA, TSS/TTA), and ash, moisture, and fiber contents in blueberries of the cultivar Biloxi grown under tropical climate conditions (without chilling hours), in Brasilia, DF, Brazil. The trial followed a randomized-block design with three replications. Plants received either severe pruning removing lateral branches (SPRLB) or severe pruning maintaining lateral branches (SPMLB) in winter, spring, summer or autumn; fruit harvested over the subsequent four weeks was analysed for DPPH radical-scavenging capacity, total soluble solids (TSS), titratable acidity (TTA), TSS/TTA ratio, ash, moisture and fibre contents. Pruning season exerted the strongest effect. Autumn pruning—regardless of type—produced the highest antioxidant activity and elevated TSS. SPRLB increased TTA, whereas SPMLB enhanced the TSS/TTA ratio during warmer seasons. These findings demonstrate that pruning season plays a key role in enhancing blueberry fruit quality under tropical conditions.

O maracujazeiro azedo (Passiflora edulis Sims) é uma frutífera amplamente cultivada no Brasil, seu maior produtor e consumidor. Porém, a cultura possui um rendimento médio nacional que está abaixo do potencial produtivo, devido principalmente a ocorrência de múltiplas doenças. Dessa forma, o objetivo do estudo foi realizar a avaliação e seleção de linhagens de maracujazeiro, quanto ao desempenho agronômico. Foi conduzido experimento em campo com delineamento em blocos ao acaso, com 3 repetições e 3 plantas por parcela. Foram avaliadas 86 linhagens de maracujá, e a testemunha BRS Rubi do Cerrado. Ao longo de 34 semanas, foi avaliada semanalmente, a produtividade comercial, e após, foi estimada a produtividade comercial por hectare ano (t ha-1 ano-1), considerando uma população de 2000 plantas por hectare. A massa média de frutos foi obtida dividindo-se a produção total pelo número de frutos colhidos. A partir dos dados foi observado que as linhagens (42L, 91L, 163L e 151L) se destacaram pela alta produtividade de frutos e a linhagem (16L) pela produção de frutos ideais para o produtor devido ao maior valor agregado. As linhagens avaliadas mostraram variação significativa na massa dos frutos, especialmente nas classificações 1A, 2A e 3A. O número total de frutos também variou consideravelmente entre as linhagens, com algumas alcançando até 125 mil frutos/ha/ano. O resultado demonstra a importância de realizar uma seleção de linhagens de maracujá para obtenção de uma variedade de alta produtividade em relação as variedades comerciais.

The tomato culture show great economic importance in Brazil, with its high costs with fertilizers and labor. Thus, understanding the agronomic characteristics can provide better cultivation techniques in the productive fields. With this in mind, this study aimed to verify the relationship between agronomics characteristics measured in plants grown with four different fertilizer doses and four conduction systems. The experimental field was located in the Distrito Federal region. The experimental design was done with randomized blocks, with 3 replications and 10 pits per plot, in a simple factorial scheme (4 x 4), which consisted of four fertilizer doses and four conduction systems involving one or two plants per pit, with one or two stems each. The characteristics evaluated were estimated yield, average fruit mass, number of fruits per plant, number of fruits per pit, total production per plant and per pit, longitudinal and transversal diameters. Positive and significant correlations were found between agronomic parameters, considering the conduction types, for the number of fruits and production, number of fruits and fruit mass. The estimated yield showed a positive correlation with the number of fruits in the fertilizer dose. From the results, it was possible to understand that the ratio of diameter and fruit mass is important to the farmer, being possible to carry out an approximation of fruit classification based on its diameter without weighing them.

Global blueberry production more than quadrupled between 2010 and 2022. One of the factors contributing to this production growth was the development of new cultivars with little or no chilling requirements, capable of thriving in tropical regions. Therefore, the objective of this study was to assess the growth and fruit yield of blueberry plants (Biloxi cultivar) subjected to different pruning types and timings in the Distrito Federal (DF), Central-West region of Brazil. The experiment was conducted in an open field, using a randomized complete block design with 3 replications and 10 plants per plot, totaling 480 plants. The plants were grown in pots using a fertigation system and were subjected to two types of pruning (severe pruning and regular pruning) in the different seasons of the year. The plants were evaluated for vegetative growth, fruit yield, number of fruits per plant, mean fruit weight, and fruit transverse and longitudinal diameters. The results showed that Biloxi blueberry can be grown under the climate conditions of the central region of Brazil, during the four seasons of the year, despite the tropical climate conditions and no occurrence of temperatures lower than 7.2 °C. Higher fruit yields were found when pruning was performed in winter or spring. Severe pruning resulted in higher fruit yields compared to regular pruning in winter. Summer and autumn pruning treatments reduced fruit yield; however, it is an alternative to extend the production window of this crop in Brazil.

O consumo de vitaminas e nutrientes é importante para melhorar a imunidade do corpo e da saúde. Alguns alimentos são conhecidos como excelentes fontes de nutrientes, por exemplo, o feijão como fonte de ferro ou a laranja de vitamina C. Sendo assim, o estudo teve o objetivo de verificar os possíveis usos do manjericão como planta funcional, e as diferenças entre onze genótipos de manjericão avaliando os teores de macro e micronutrientes, cultivados em campo no Distrito Federal. O delineamento experimental foi de blocos casualizados, com 11 tratamentos (genótipos) e três repetições. As características avaliadas foram Magnésio (Mg), Fósforo (P), Potássio (K), Cálcio (Ca), Manganês (Mn), Ferro (Fe), Cobre (Cu) e Zinco (Zn). O genótipo MARC se destacou por apresentar valores elevados de Magnésio (Mg), Cálcio (Ca), Fósforo (P) e Zinco (Zn) em relação aos padrões estabelecidos pela tabela TACO. Desta forma, foi verificado que o manjericão pode ser uma interessante fonte de Mg, P, K, Ca e Zn, além da cultura apresentar variabilidade genética importante para o melhoramento genético de plantas.

The tomato, a rich source of essential nutrients such as vitamins A and C, potassium, and antioxidants, plays a crucial role in human nutrition, promoting health and preventing diseases. In Brazil, its production is vital, involving significant resources and labor. The correct nutritional management of the crop can improve the nutritional attributes of tomato fruits, therefore the correct use of fertilizers is of great importance due to the high need for phosphorus, nitrogen and potassium, throughout the crop cycle. Nutritional management is of great importance in tomato fields due to its high fertilizer requirements throughout the entire crop cycle. This study aimed to assess the effect of different fertilizer doses and management systems on the physicochemical characteristics of tomatoes. The experiment followed a factorial design with five fertilizer doses (A0: 0%; A1: 50%; A2: 100%; A3: 150%; A4: 200% of the recommended dose) and four conduction systems, with three replications. Productivity, lycopene content, total soluble solids (TSS), nitrogen, phosphorus, potassium, calcium and magnesium fruit contents were evaluated. The results showed that higher fertilizer doses increased lycopene levels, reaching 80 μg g-1 with 200% fertilization, while 0% provided 30 μg g-1. Total soluble solids above 4°Bx were observed at doses above 150%, regardless of planting density. Nitrogen content reached 26 mg·100 g-1f.m., favored by lower densities. Calcium was influenced by fertilizer doses, with higher concentrations at 150%. In conclusion, the application of 150% fertilizer dose improved the nutritional quality of tomatoes, and the 200% dose provided suitable levels of TSS and lycopene for processing.

The commercial propagation of Caryocar brasiliense Cambess is hindered by several factors, including seed dormancy and low cutting survival rates. Air layering studies are needed to overcome these limitations. Previous studies have reported the influence of substrates on the rooting of air layers for different species. Therefore, the objective of this study was to evaluate the influence of substrates on air layering of Caryocar Brasiliense. An experiment was conducted with eight stock plants located at Embrapa Cerrados, Distrito Federal, Brazil, using different substrates, including Bioplant®, coconut fiber, a mixture of Bioplant® and coconut fiber in 3:1, 1:1, 1:3 proportions, rice husk biochar, vermiculite, sawdust, soil, and sand. Each treatment was replicated four times. After five months, the survival rate, callus formation, rooting percentage, root length, fresh and dry root mass, and rooting vigor were evaluated. The survival and callus formation rates in all substrates were above 95%. Bioplant® substrate provided the highest rooting percentage (77%), fresh and dry root mass (17.08g and 3.16g, respectively), while soil provided the lowest rooting percentage (17%) and fresh and dry root mass (0.1g and 0.02g, respectively). The average root length was 6.63 cm in the 1:1 mixture. Based on the evaluated characteristics, Bioplant® is the most suitable substrate for the propagation of C. brasiliense stock plants by air layering. The results suggest that air layering is a viable alternative to the vegetative propagation of Caryocar brasiliense stock plants.

The definition of vegetative propagation protocols is important for the production of Caryocar brasiliense Cambess plants, for the formation of commercial orchards. Therefore, the objective of this study was to evaluate the substrate’s chemical characteristics influence on Caryocar brasiliense air layering. For this, a randomized block experiment with five substrates was carried out in eight plants. The following substrates were evaluated: Bioplant® commercial substrate; coconut fiber; a mixture of Bioplant® and coconut fiber in (1:1; 1:3; 3:1) proportions. After 150 days, the air layers were cut and evaluations of survival, callusing and rooting percentages, root length, dry and fresh root matter, rooting vigor and lignification were carried out. In laboratory, chemical and physical characterizations of the substrates were undertaken. The results showed that the rooting percentage varied from 40% to 77%. Rooting of Caryocar brasiliense air layers is optimized when phosphorus, calcium, magnesium and CEC in the substrate are above 3.0 mg dm-3, 7.0 cmolc dm-3, 3.5 cmolc dm-3 and 17 cmolc dm-3, respectively. Sodium and sodium saturation of the substrate must be below 1.4 cmolc dm-3 and 6%, respectively. Strong, positive and significant correlations were observed between rooting and P, Ca, Mg and CEC.

Objective: The aim of the present study was to evaluate the performance of four banana cultivars (Grand-Naine, Prata-Anã, BRS-Tropical, and BRS-Conquista) in the Brazilian Savannah, Brasília, Federal District. Theoretical framework: Banana tree is responsible for providing one of the most consumed and appreciated fruits in all regions of the world, and is largely cultivated in tropical countries. Banana production is a growing activity in Brazil, mainly in family farming, due to its economic and social importance. Methods: The study was implemented at the experimental field of the Água Limpa Farm, which belongs to the University of Brasília, FD, Brazil. The essay was conducted in a randomized block design, consisting of four treatments and four replications. The evaluated variables were: total bunch weight, number of fruits per bunch, number of hands per bunch, fruit length, and fruit diameter. Results and discussion: Significant differences were found for all variables evaluated. The coefficient of variation was lower than 30% for all analyzed characteristics, indicating a good experimental accuracy. Bunch weight, fruit length, and fruit diameter of the cultivar Grand-Naine were significantly higher (Skott Knott 5%) than those of the other cultivars evaluated. BRS-Conquista had the highest number of fruits per bunch and number of hands per bunch. The results showed a positive significant correlation between number of fruits per bunch and number of hands per bunch. The estimates of the genetic parameters for the evaluated characteristics showed favorable conditions for selection, with CVg to CVe ratio higher than 1, and heritability ranging from 85 to 99%. Implications of the research: The Grand-Naine cultivar came out on top in terms of the performance evaluated under the edaphoclimatic conditions of the Brazilian Savannah, Brasília, Federal District, and it was also established the performance of BRS-Conquista, Prata-Anã and BRS-Tropical in this region. Originality/value: Pointing out the most important genetic parameters guides genetic improvement actions for these cultivars in the region, as well as assisting new breeding programs.

In agroindustry, quinoa is considered a functional food due to its health benefits. However, it is necessary to identify genotypes that have better physicochemical characteristics and high antioxidant capacity for selection in breeding programs. This study aimed to evaluate the physicochemical composition and antioxidant capacity of quinoa genotypes originating from Brazil, Colombia, and Ecuador grown in the Brazilian Savanna (Cerrado) environment. The sowing was carried out at Fazenda Água Limpa, Faculdade de Agronomia e Medicina Veterinária, Universidade de Brasília, located at 15º56' S and 47º55' W, at an altitude of 1,100 m. The physicochemical analysis was performed in 2021 at the Centro de Pesquisa em Alimentação of the Universidade Passo Fundo, Rio Grande do Sul, and the antioxidant capacity analysis was carried out at the Universidad de Santiago de Chile. The moisture, ash, protein, carbohydrates (CHO), crude fiber, lipid, and antioxidant capacity were determined. The original data was submitted to analysis of variance, by the F test (P≤0.05), and the means compared by the Tukey test. Linear correlations (Fischer) (P≤0.01) and (P≤0.05) and hierarchical clustering analysis by the Ward method were performed. The genotypes showed variability in physicochemical characteristics and antioxidant activity. CHO was the major compound present in the seeds, exhibiting an average of 50.16%, the protein average was 15.27%, with the P88 genotype standing out with 16.28%. The lipids, fiber, and ash average content were 3.24, 14.13, 6.0%, respectively. CHO showed a positive correlation with the lipid parameter (r=0.858) and a significant negative correlation with protein (r=-0.785). The Aurora cultivar expressed the highest antioxidant activity (1.96±0.01 mg Trolox/g).