-Our study was conducted in the experimental field of the Department of Technology and Social Sciences (DTCS) of the State University of Bahia -UNEB, Juazeiro-BA. The experimental design was comprised of randomized blocks, sub-subdivided in plots, with four replicates comprising the plots of three different shading methods, gray shading screen (GS), red shading screen (RS), and blue shading screen (BS), and the control treatment with no shading. The subplots comprised three mini-tomato cultivars ("Sweet Million", "Red Sugar", and "Shani"), and sub-subplots consisted of seven sampling times. The traits evaluated were: dry matter accumulation in leaves, stems, roots, and fruits, total dry matter, shoot length, root length, total number of fruits, and overall yield. The results of the growth analysis showed that dry matter accumulation in organs of mini tomatoes was similar in all treatments and that the highest total dry matter accumulation occurred under RS. In all treatments, fruit was the preferential drainage; however, the cultivar "Red Sugar" showed higher dry matter accumulation in other plant organs. "Red Sugar" also showed the highest number of fruits per plant; however, when we evaluated total productivity, "Sweet Million" and "Shani" showed similar, higher values than "Red Sugar".Keywords: Solanum lycopersicum. Shading screens. Growth analysis. Red Sugar. Sweet Million. Shani. IMPACTO DOS DIFERENTES AMBIENTES DE SOMBREAMENTO NO CRESCIMENTO E PRODUTIVIDADE DE TRÊS CULTIVARES DE MINITOMATESRESUMO -O trabalho foi conduzido no campo experimental do Departamento de Tecnologia e Ciências Sociais (DTCS), Campus III, da Universidade do Estado da Bahia -UNEB, Juazeiro-BA. O delineamento experimental foi em blocos casualizados, com parcelas subsubdivididas, com quatro repetições, as parcelas compostas de três ambientes sombreados, tela de sombreamento cinza, tela de sombreamento vermelha, e tela de sombreamento azul, mais o tratamento controle, sem sombreamento, as subparcelas formadas por três cultivares de minitomates ("Sweet Million", "Red Sugar", e "Shani") e as sub-subparcelas constituída de sete épocas de amostragens das plantas. As características avaliadas foram: acúmulo de massa seca nas folhas; no caule; nas raízes; nos frutos e total, além do comprimento da parte aérea, comprimento da raiz, o número total de frutos e produtividade. Os resultados de análise de crescimento apresentaram acúmulo de massa seca nos diferentes órgãos das plantas de minitomates, para todos os tipos de ambientes e que o maior acúmulo de massa seca total ocorreu no ambiente com tela vermelha. Em todos os ambientes analisados, o dreno preferencial da planta foi o fruto, contudo, a cultivar Red Sugar acumulou maior massa seca nos outros órgãos da planta em comparação com as demais cultivares. A cultivar Red Sugar obteve a maior quantidade de frutos por planta, entretanto, quando avaliou-se a produtividade total, as cultivares Sweet Million e Shani não diferiram entre si, sendo, superiores aos valores obtidos para a cultiva...

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Shading screens are widely used to control excessive solar radiation, thereby changing plant growth. Thus, through physiological indices the objective was to evaluate the growth of three cultivars of minitomatoes under colored meshes. The experiment was conducted from April to July in the DTCS / UNEB experimental field in experiment DBC with subdivided plots, and four replicates, comprised of three shaded environments and the control treatment, three cultivars, and seven plant sampling seasons. For growth analysis, we used the destructive method, total dry matter was determined after drying it in an oven at 65°C. The total leaf area (LAI) was obtained using the software QUANT. Results showed that there was no interaction between environments and the other factors. Regarding leaf area index, cvs. Shani and Sweet Million stood out in all environments, whereas cv. Red Sugar had a similar behavior in all environments. Shani obtained the best indices in open sun environment and in the environment covered with red shading screen, and Sweet Million obtained the best index under gray shading screen. Red Sugar had the lowest LAI, and consequently, the lowest SLA and LAR. On the other hand, it showed the highest RPF, since it obtained the highest dry matter in leaves compared to the other cultivars. Cvs. Shani and Sweet Million showed the best: TAL, TCR, TCA and TCC.

Cacao is native to the Amazon rainforest and has adapted well to the climate and soils of southern Bahia. The potential expansion of cacao farming to non-traditional areas could generate foreign exchange for the country by reducing imports or even allowing the country to return to the role of cocoa bean exporter. It is known that nitrogen fertilization is essential for cacao cultivation, due to its high demand for this nutrient. Accordingly, the influence of fertilization of two nitrogen sources (urea and calcium nitrate), on total soluble protein (PTN), total soluble sugars (AST), reducing sugars (RA), sucrose, Nitrate Reductase enzyme (NR) activity and chlorophyll indexes of cloned cacao in the Lower São Francisco Valley were investigated. The experimental format was a randomized complete block design, in a 5 x 2 factorial scheme, the first factor being five cacao clones (PH-16, CCN-51, PS-1319, CCN-10 and TSH-1188), and the second factor, two sources of nitrogen (calcium nitrate and urea), with three replicates. The different nitrogen sources presented different behavior in relation to the physiological characteristics of the clones evaluated. Regardless of the nitrogen source, the nitrate reductase enzyme showed greater levels of translation activity in cacao leaf than in root tissue.