RESUMOAvaliou-se o efeito da aplicação em excesso de fertilizantes via irrigação em solos com diferentes níveis de salinidade, sobre as variáveis produtivas do tomateiro em ambiente protegido localizado no Departamento de Engenharia de Biossistemas da ESALQ/USP, Piracicaba-SP. O delineamento estatístico foi o em blocos casualizados em esquema fatorial 6x2 com quatro repetições, em que os fatores consistiram em seis níveis iniciais de salinidade do solo (S 1 = 1,62; S 2 = 2,40; S 3 = 2,98; S 4 = 3,48; S 5 = 4,63 e S 6 = 5,82 dS m -1 ) e em dois manejos da fertirrigação (M 1 -Adubos aplicados em fertirrigação obedecendo à curva de absorção de nutrientes da cultura e M 2 -Cultivo sem aplicação de fertilizantes via água de irrigação). As variáveis fitomassa fresca de frutos e número de frutos foram afetadas estatisticamente, tanto pelo manejo quanto pela salinidade do solo com reduções de 38,82 e 27,31 % para o manejo M 1 . A interação entre (salinidade x manejo) e a salinidade isolada influenciou significativamente os componentes estudados, exceto para fitomassa seca do caule e raiz na interação. O manejo M 1 foi superior em todos os componentes de produção estudados quando comparado ao manejo M 2 . O limiar para a cultivar foi superior ao encontrado na literatura. Palavras-chave:Lycopersicon esculentum Mill, condutividade elétrica do solo, fertilizantes químicos, solução no solo Fertilizer salts and fertigation management in tomato cultivation in greenhouse ABSTRACT The effect of application of fertilizers in excess through irrigation in soils with different levels of salinity was evaluated on variables of tomato production, in a greenhouse located in Department of Biosystems Engineering of ESALQ/USP, in Piracicaba, Brazil. The experimental design was randomized blocks, in a factorial scheme 6 x 2 with four replications, the factors consisted in six levels of initial soil salinity (S 1 = 1.62, S 2 = 2.40, S 3 = 2.98, S 4 = 3.48, S 5 = 4.63 and S 6 = 5.82 dS m -1 ) and two fertigation managements (M 1 -Fertilizer applied in fertigation obeying the nutrient absorption curve of crop, and M 2 -Cultivation without application of fertilizers through irrigation water). The variables fresh biomass of fruit and number of fruits were statistically affected by both factors-types of management and salinity levels with reductions of 38.82 and 27.31% for the M 1 management. The interaction between salinity x management and salinity isolated significantly influenced components studied, except dry biomass of stem and root for interaction. The management M 1 performed better for all yield components studied when compared to M 2 management. The threshold for the cultivar was higher than that found in the literature.
The use of salt stress attenuators is considered an important tool to minimize the deleterious effects of salts. However, its application to chives (Allium schoenoprasum L.) has not been studied. This study aimed to evaluate the induction of salt stress tolerance in chives plants in relation to growth and enzymatic reactions, when subjected to different salinity levels of the nutrient solution, after acclimation of seeds with hydrogen peroxide (H2O2) for 24 h. The experiment was conducted in a greenhouse, where chives seeds were acclimated by H2O2 at concentrations of 0.0, 0.15, 0.30, 0.45 and 0.60 mmol. After germination, the plants were cultivated in hydroponic system with electrical conductivities of 1.0, 2.0, 3.0, 4.0 and 5.0 dS m -1 . Plant height, length and number of leaves, H2O2 content, malondialdehyde and catalase (CAT) activity were evaluated in chives plants. The increase in the salinity of the nutrient solution up to 5 dS m -1 reduced by 5.88%, 17% and 9.63% plant height, leaf length and number of leaves, respectively. It was observed that the acclimation of chives seeds with H2O2 at 0.45 mmol g -1 fresh mass in plants that were cultivated in nutrient solution of 3.73 dS m -1 led to maximum CAT activity, minimizing the deleterious effects of nutrient solution salinity on plant growth.
ABSTRACT:The use of tools such as process capability index for irrigation aims to observe how this irrigation is adequate in terms of quality. The aim of the study was analyzing the Christiansen uniformity coefficient and the flow of a drip irrigation system with self-compensating emitters under water different salt concentrations, using the process capability index. The research was conducted in a greenhouse at the Federal University of Campina Grande (UFCG). The experimental design was a randomized block in a factorial 5 x 2 with three replications, the factors consisted of five levels of irrigation water salinity (CEw) (0.6, 1.5, 2.5, 3.5 and 4.5 dS m -1 at 25°C) and two running times (0 and 350 hours of operation). The Christiansen uniformity coefficient (CUC) for new and used emitters was greater than 90%, in different salt concentrations studied. The flow of emitters is maintained within the statistical quality control, since management and maintenance operations are made after 350 hours of operation. The potential process capability index for the Christiansen uniformity coefficient was higher than recommended for new and used emitters, being the process within the required specifications.
Este artigo apresenta o uso do ambiente de autoria Scratch para favorecer a construção de conhecimentos matemáticos e o desenvolvimento do pensamento formal em adolescentes. Apresenta uma contextualização sobre o uso das tecnologias digitais no contexto educacional, o desenvolvimento do pensamento formal, o ambiente de experimentação criado com o ambiente de autoria Scratch visando que os estudantes pudessem ensejar a aquisição de conhecimentos sobre ângulos de reflexão e incidência e por fim os resultados obtidos por meio das observações.
This challenge arises as a consequence of studies and reflections on pedagogical practices with the use of ?educational software for mobile devices?. The possibilities of using this resource in the classroom may be favorable to the educator as a technology accessible to the inclusion of students with high-functioning autism spectrum disorder (ASD). Given this context, our goal is to develop a ?QUIZ? for mobile devices - using the APP-inventor app aimed at improving the social interactions of students with high- functioning autism. Therefore, we believe that the application of a ?QUIZ? with school daily expressions, may improve social interactions as well as communication, a common difficulty that ASD students presents.
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