Curso diário fotossintético de plantas de copo-de-leite

The calla lily ornamental plant (Zantedeschia aethiopica) is grown and marketed in many countries. Studies on daily variation in photosynthesis are critical for understanding how a plant behaves in its growing environment. The objective of this study was to evaluate the daily photosynthetic course of calla lily plants grown in pots in a greenhouse under 50% shade. Gas exchange (gs, A, E, Ci, WUE, iWUE, and iCE) and chlorophyll indices (a, b, and total) were evaluated from 7:00 a.m. to 5:00 p.m. over three days. The values of all variables were greater at high temperatures (11:00 a.m. to 1:00 p.m.), except for gs, Ci, and chlorophyll b, which were higher at low temperatures (7:00 to 9:00 a.m.) Therefore, it is suggested that calla lily producers maintain the water status between 11:00 a.m. and 1:00 p.m. to optimize photosynthetic processes, and consequently, the growth and development of this plant. Correspondingly, irrigation of this crop should be performed prior to the interval mentioned above.A planta ornamental copo-de-leite (Zantedeschia aethiopica) é cultivada e comercializada em muitos países. Estudos sobre a variação diária da fotossíntese são fundamentais para entender como uma planta se comporta em seu ambiente de crescimento. O objetivo deste trabalho foi avaliar o curso diário fotossintético de plantas de copo-de-leite cultivadas em vasos em casa de vegetação sob 50% de sombreamento. As trocas gasosas (gs, A, E, Ci, WUE, iWUE e iCE) e os índices de clorofila (a, b e total) foram avaliados das 7h às 17h por três dias. Os valores de todas as variáveis ​​foram maiores em temperaturas mais elevadas (11h às 13h), exceto para gs, Ci e clorofila b, que foram maiores em temperaturas mais baixas (7h às 9h). Com isso, sugere-se que os produtores de copo-de-leite mantenham o estado hídrico das plantas entre as 11h00 e as 13h00 para otimizar os processos fotossintéticos e, consequentemente, o crescimento e desenvolvimento desta planta. Da mesma forma, a irrigação desta cultura deve ser realizada antes do intervalo mencionado acim

RESPOSTAS FISIOLÓGICAS DE PLÂNTULAS DE Erythrina verna SOB TRATAMENTOS PRÉ-GERMINATIVOS DE SEMENTES E PROFUNDIDADE DE SEMEADURA

http://dx.doi.org/10.5902/1980509817463The objective of this work was to determine the most appropriate pre-germinative treatment of seeds and sowing depth for the production of Erythrina verna seedlings. For this, the following pre-germinative treatments were initially studied: control (intact seeds); mechanical scarification on the area opposite to hilum, with the help of sandpaper number 80; mechanical scarification on the raphe region, with the help of sandpaper number 80; soaking in water for 24 hours. In a second experiment, the seeds were sown at the depths of 1, 2, 3, 4, 5 and 6 cm. After 15 days, we evaluated the percentage of emergence, emergence speed index, shoot length and seedling root length, dry weight of shoot and root dry mass of seedlings. The seeds of Erythrina verna present coat dormancy that can be broken by mechanical scarification in the area opposite to the hilum. The seedlings present the best physiological quality when seeds are sowing at 1 to 3 cm depth, where the highest percentages of emergence, speed of emergence index, length of shoot and length root and shoot dry mass are obtained.http://dx.doi.org/10.5902/1980509817463Este trabalho objetivou determinar o melhor tratamento pré-germinativo de sementes e a profundidade de semeadura mais adequada para a produção de mudas de Erythrina verna. Para isso, os seguintes tratamentos pré-germinativos foram estudados: testemunha (sementes intactas), escarificação mecânica na região oposta ao hilo com auxílio de lixa no 80, escarificação mecânica na região da rafe com auxílio de lixa no 80, embebição em água por 24 horas. Em um segundo experimento, as sementes foram semeadas nas profundidades de 1, 2, 3, 4, 5 e 6 cm. Após 15 dias avaliou-se a porcentagem de emergência, índice de velocidade de emergência, comprimento da parte aérea e comprimento da raiz das plântulas, massa seca de parte aérea e massa seca de raiz das plântulas. As sementes de Erythrina verna apresentam dormência tegumentar que pode ser superada pela escarificação mecânica na região oposta ao hilo. As plântulas apresentam a melhor qualidade fisiológica quando as sementes são semeadas à profundidade de 1 a 3 cm, onde a maior porcentagem de emergência, índice de velocidade de emergência, comprimento da parte aérea e da raiz e massa seca da parte aérea são obtidos

Hydroponic growth of lisianthus as cut flower under nutrient film technique

O objetivo deste trabalho foi avaliar as características produtivas e comerciais do cultivo de quatro cultivares de lisianto (Eustoma grandiflorum) em três soluções nutritivas em sistema de fluxo laminar de nutrientes (NFT). Utilizou-se o delineamento em blocos casualizados, em esquema fatorial 4x3, com três repetições. Os tratamentos foram compostos de quatro cultivares (Echo Champagne, Mariachi Pure White, Balboa Yellow e Ávila Blue Rim) e três soluções nutritivas (Teste, Steiner modificada e Barbosa). O sistema NFT é uma alternativa viável para o cultivo de lisianto nas soluções Barbosa e Teste. A cultivar Echo Champagne foi superior quanto ao ciclo, período em produção, altura da haste floral, número de folhas, diâmetro de botão e produção de massa fresca e seca, enquanto a cultivar Mariachi Pure White se destacou quanto ao período em produção. A cultivar Ávila Blue Rim apresentou maior período de produção, número de flores e produção de massa de matéria fresca e seca, enquanto a cultivar Balboa Yellow apresentou maior período em produção e diâmetro de botão.The objective of this work was to evaluate yield and commercial traits of lisianthus (Eustoma grandiflorum) flowers growth in nutrient film technique (NFT). The experimental design was in randomized blocks, in factorial scheme (4x3), with three replicates. The treatments were four cultivars (Echo Champagne, Mariachi Pure White, Balboa Yellow and Ávila Blue Rim) and three nutrient solutions (Test, modified Steiner and Barbosa). The NFT system is a feasible alternative for the growth of lisianthus in Barbosa and Test solutions. The cultivar Echo Champagne was superior for cycle, length of production, height of flower stem, number of leaves, diameter of the bud flower and fresh and dry weight production, while the cultivar Mariachi Pure White was superior for length of production. The cultivar Ávila Blue Rim showed good length of production, number of flowers and fresh and dry matter production, while the cultivar Balboa Yellow had long length of production and bud flower diameter

Production and quality of ornamental peppers cultivated under colored shade nets

The cultivation of ornamental peppers in places with high temperature and incidence of solar radiation limits the production and quality of plants and fruits. The colored shade nets were introduced and adopted, because they reduce the temperature and intensity of solar radiation, as well as, low cost and simple to handle. The aimed was to evaluate the production and quality of C. chinense and C. frutescens cultivated under colored shade nets. The experiment was developed in the Floriculture Sector of the Agronomy Department of the Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil from February to August 2021 in entirely randomized design.  C. chinense and C. frutescens were cultivated under red, pearl and aluminet nets with 35% shading and without net. At 150 days, production variables were quantified. The red net reduced the maximum temperature by at 4.1ºC and the pearl and aluminet nets reduced the minimum temperature by 3ºC. The maximum and minimum relative humidity was increased by 2.6 and 8.5%, respectively, by the red net. The pearl net obtained the lowest percentage of solar radiation incidence. Plant height was greater in the red and pearl nets, and C. frutescens. The diameter and stem fresh matter did not differ statistically between treatments. Root length was greater in the red and aluminet nets. The longitudinal and transverse canopy ratio was higher in C. chinense cultivated under the aluminet net. The number of leaves and leaves fresh matter was higher in pearl and aluminet net, and in C. frutescens, but leaves dry matter was higher in C. chinense. The number of flower buds and flowers, and flower buds dry matter was higher in C. chinense. The root fresh matter and dry matter was greater in C. chinese. The use of colored shade nets during the cultivation period effectively reduced temperature and light intensity. The aluminet net in association with C. chinense are recommended considering the compactness of height, pot coverage, greater number, shape and arrangement of fruits.The cultivation of ornamental peppers in places with high temperature and incidence of solar radiation limits the production and quality of plants and fruits. The colored shade nets were introduced and adopted, because they reduce the temperature and intensity of solar radiation, as well as, low cost and simple to handle. The aimed was to evaluate the production and quality of C. chinense and C. frutescens cultivated under colored shade nets. The experiment was developed in the Floriculture Sector of the Agronomy Department of the Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil from February to August 2021 in entirely randomized design.  C. chinense and C. frutescens were cultivated under red, pearl and aluminet nets with 35% shading and without net. At 150 days, production variables were quantified. The red net reduced the maximum temperature by at 4.1ºC and the pearl and aluminet nets reduced the minimum temperature by 3ºC. The maximum and minimum relative humidity was increased by 2.6 and 8.5%, respectively, by the red net. The pearl net obtained the lowest percentage of solar radiation incidence. Plant height was greater in the red and pearl nets, and C. frutescens. The diameter and stem fresh matter did not differ statistically between treatments. Root length was greater in the red and aluminet nets. The longitudinal and transverse canopy ratio was higher in C. chinense cultivated under the aluminet net. The number of leaves and leaves fresh matter was higher in pearl and aluminet net, and in C. frutescens, but leaves dry matter was higher in C. chinense. The number of flower buds and flowers, and flower buds dry matter was higher in C. chinense. The root fresh matter and dry matter was greater in C. chinese. The use of colored shade nets during the cultivation period effectively reduced temperature and light intensity. The aluminet net in association with C. chinense are recommended considering the compactness of height, pot coverage, greater number, shape and arrangement of fruits

Initial growth of Calendula officinalis L. plants treated with paclobutrazol

Calendula officinalis L. is largely used in composition in beds and like cutted flowers. On the other hand, the height (30 – 60 cm), difficult the cultivate and sales like potted plant, owing to the tipping of pots and for the disposition of plants on the tables.  Paclobutrazol (PBZ) is a vegetal regulator that reduces the growth of plants.   The purpose of this study was to evaluate the initial growth of C. officinalis L. treated with PBZ. The experiment was conducted in a greenhouse in the Floriculture Sector, of Agronomy Department, of Universidade Federal de Viçosa in October a November of 2020. The experiment was conducted in complety randomized desing and treatments were control, 2500, 5000, 7500 e 10000 ppm of PBZ doses with five repetitions. Two applications of PBZ doses were realized, being the first 15 days and the second 30 days after transplantation.  Plant height, leaf area, stem length and diameter, root length, leaves number and photosynthetic pigments were quantified.   PBZ, regardless of concentration, reduced plant heigth, leaf area, stem length, and diameter. Root length, leaves number and photossyntetic pigments did not significant among doses aplied. The initial growth of C. officinalis L. was reduced with PBZ doses.Calendula officinalis L. is largely used in composition in beds and like cutted flowers. On the other hand, the height (30 – 60 cm), difficult the cultivate and sales like potted plant, owing to the tipping of pots and for the disposition of plants on the tables.  Paclobutrazol (PBZ) is a vegetal regulator that reduces the growth of plants.   The purpose of this study was to evaluate the initial growth of C. officinalis L. treated with PBZ. The experiment was conducted in a greenhouse in the Floriculture Sector, of Agronomy Department, of Universidade Federal de Viçosa in October a November of 2020. The experiment was conducted in complety randomized desing and treatments were control, 2500, 5000, 7500 e 10000 ppm of PBZ doses with five repetitions. Two applications of PBZ doses were realized, being the first 15 days and the second 30 days after transplantation.  Plant height, leaf area, stem length and diameter, root length, leaves number and photosynthetic pigments were quantified.   PBZ, regardless of concentration, reduced plant heigth, leaf area, stem length, and diameter. Root length, leaves number and photossyntetic pigments did not significant among doses aplied. The initial growth of C. officinalis L. was reduced with PBZ doses

Increase in oil content and changes in quality of macauba mesocarp oil along storage

Macauba is an oleaginous palm species from Latin America. It is a rich source of vegetable oil with diverse benefits. However, there are several gaps in assuring post-harvest oil quality of the mesocarp. Thus, ripe fruits were stored at room temperature for 60 days before oil extraction to evaluate fruit and mesocarp oil quality attributes. Physical (decay incidence, water activity), biochemical (specific activity of lipase), physicochemical (acidity and peroxide indices, molar absorptivity at K232 and K270, oxidative stability, total carotene content and mesocarp colour) analyses were carried out. Results show that nonlinear sigmoid response was obtained for most of the parameters evaluated. Decaying reactions related to microorganism’s growth, free fatty acid release and oxidation took place along storage. However, the overall oil quality was in the acceptable limits up to 20 days of storage. It is much further than palm oil, the main source of oil in the world

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements