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Within the genetic variability of the Capsicum genus there are plants with ornamental potential, but awry height required by the market. Paclobutrazol (PBZ), gibberellin retardant and growth inhibitor, is normally used as alternative to reduce plant height. The objective was to evaluate the PBZ (0, 25, 50 and 75 mg L-1) effect on plant height of eight pepper genotypes. Seven accessions [BGH 1032, BGH 1039, BGH 7073 (C. annuum), BGH 4285, BGH 4199, BGH 4355 and BGH 6371 (C. chinense)] of the germplasm bank from Universidade Federal de Viçosa and one access [MG 302 (C. annuum)] from the germplasm bank of the Empresa de Pesquisa Agropecuária de Minas Gerais were evaluated. The PBZ application was ineffective in altering plant architecture of BGH 6371. PBZ at 25 mg L-1 resulted in plants with better ornamental characteristics of the accesses BGH 1032 and BGH 1039. Considering the cost-benefit, the indicated dose for BGH 4285, BGH 7073 and MG 302 access is 25 mg L-1 PBZ. The PBZ application in BGH 4199 and BGH 4355 accesses, despite reducing plant height, did not improve the ornamental characteristics, resulting in plants without canopy pattern.

Germplasm classification by species requires specific knowledge on/of the culture of interest. Therefore, efforts aimed at automation of this process are necessary for the efficient management of collections. Automation of germplasm classification through artificial neural networks may be a viable and less laborious strategy. The aims of this study were to verify the classification potential of Capsicum accessions regarding/ the species based on morphological descriptors and artificial neural networks, and to establish the most important descriptors and the best network architecture for this purpose. Five hundred and sixty-four plants from 47 Brazilian Capsicum accessions were evaluated. Neural networks of multilayer perceptron type were used in order to automate the species identification through 17 morphological descriptors. Six network architectures were evaluated, and the number of neurons in the hidden layer ranged from 1 to 6. The relative importance of morphological descriptors in the classification process was established by Garson's method. Corolla color, corolla spot color, calyx annular constriction, fruit shape at pedicel attachment, and fruit color at mature stage were the most important descriptors. The network architecture with 6 neurons in the hidden layer is the most appropriate in this study. The possibility of classifying Capsicum plants regarding/ the species through artificial neural networks with 100 % accuracy was verified.

The use of essential oils (EO's) as feed additive has been explored as tool to improve fish growth and health. The aim of this study was to evaluate the oregano essential oil (OEO) (Origanum vulgare) dietary supplementation for the catfish Lophiosilurus alexandri. Four diets supplemented with different OEO levels (0.0, 1.0, 2.0 and 4.0 g kg−1) were evaluated in a feed trial conducted with fish of 15.7 ± 1.8 g and 9.5 ± 0.45 cm for 13 weeks. Were evaluated growth performance, biochemical parameters, intestinal histomorphometry, whole‐body composition and muscle growth. Polynomial analysis showed that weight gain, length gain and specific growth rate were improved in fish fed with OEO supplemented diets, being 2.37, 2.56 and 2.33 g kg−1 the respective levels that maximize these variables. Plasma glucose, cholesterol, triglycerides, LDL and HDL increased with OEO levels between 1.80–2.47 g kg−1. Intestinal histomorphometry was not affected by OEO. Body protein content and hyperplasic muscle fibres were maximized with 2.10 and 2.25 g kg−1 OEO, respectively. Body moisture, total lipids, ash and hypertrophic muscle fibres were not affected by OEO. In conclusion, dietary supplementation with 2.10–2.56 g kg−1 OEO improves growth performance, body protein retention and muscle growth of L. alexandri.

The genus Capsicum has varying levels of sensitivity to ethylene. Variability knowledge allows planning post-production methodologies of potted pepper plants and can be used in breeding programs. The objective of this study was to evaluate the ethylene sensitivity of three ornamental pepper genotypes of the germplasm bank of Universidade Federal de Viçosa. Pepper plants were exposed to 10 μL L-1 ethylene during 48 hours. The flowers were highly sensitive to exogenous ethylene in all genotypes except Pimenta colorida which was moderately sensitive. Regarding leaf abscission, Pimenta colorida and Pimentão ornamental are classified as highly sensitive to ethylene application. Already the fruits responded with the early appearance of the typical coloration when ripe, except for Pimenta laranja. When fruits fell, the highest rates were observed for green fruits, followed by ripe green and ripe fruits.

1-MCP has been effectively used as an antagonist of ethylene deleterious actions in flowers and ornamental plants. The objective was to evaluate the efficiency of 1-MCP (0.0, 0.5, 1.0 and 1.5 g m-3) in maintaining post-production quality of exogenous ethylene sensitive ornamental pepper. Two commercial varieties were evaluated: Pimenta Colorida and Pimentão Ornamental, both Capsicum annuum. The pre-treatment with 1-MCP, regardless of the applied concentration, was effective in blocking the ethylene action reducing the leaves abscission, flowers and fruits of both genotypes by 100%. Plants pretreated with 1-MCP had postproduction life increased by eight and nine days for Pimenta Colorida and Pimentão Ornamental, respectively. The 1-MCP application at the concentration of 1.0 g m-3 is efficient in maintaining ornamental quality and prolonging the shelf life of Pimenta Colorida and Pimentão Ornamental.

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Apparent digestibility coefficients of nutrients and energy from diets with different ratios of crude protein and non-fibrous carbohydrates for Lophiosilurus alexandri, a carnivorous freshwater fish.