Mango is a highly perishable fruit with a short post-harvest time due to the intense metabolic activity after harvesting. In attempt to evaluate the effects of chitosan in mango fruits, it was treated with 0%, 1%, 2% or 3% of chitosan solutions, placed into plastic trays, and stored at room temperature. Changes in physical and chemical parameters were evaluated. Chitosan delayed the climacteric peak, water loss and firmness. Further, few changes in soluble solid content, titratable acidity, pH of the pulp as well as in sugar content and decreased starch degradation were observed. Altogether, our results suggest chitosan edible coating effectively prolongs the quality attributes, affecting basic mitochondrial respiration and starch degradation rate.
Guava is a typically tropical fruit highly perishable with a short shelf-life due to intense metabolic activity after harvested. In attempt to minimize the problems related to the postharvest, we evaluated the physiochemical characteristics and antioxidant system in guava fruits under chitosan coating at concentrations of 1%, 2%, and 3% stored at 25°C during 96h. The chitosan suppressed the respiratory rate, fresh weight loss, firmness and skin color with delay in the degradation of chlorophyll. In the treatment with 2% and 3% of chitosan in the solid soluble content and ascorbic acid were reduced; retarded the loss of titratable acidity during 96h after treatment. These treatment induced significant decreases in the phenylalanine ammonia-lyase activity and significantly increases of peroxidase Activity. Our results suggest that chitosan effectively prolongs the quality attributes in guava fruits after harvesting due to increases in the antioxidant processes, delaying the ripening during room temperature of storage.
Malate is a central metabolite involved in a multiplicity of plant metabolic pathways, being associated with mitochondrial metabolism and playing significant roles in stomatal movements. Vacuolar malate transport has been characterized at the molecular level and is performed by at least one carrier protein and two channels in Arabidopsis () vacuoles. The absence of the Arabidopsis tonoplast Dicarboxylate Transporter (tDT) in the knockout mutant was associated previously with an impaired accumulation of malate and fumarate in leaves. Here, we investigated the consequences of this lower accumulation on stomatal behavior and photosynthetic capacity as well as its putative metabolic impacts. Neither the stomatal conductance nor the kinetic responses to dark, light, or high CO were highly affected in plants. In addition, we did not observe any impact on stomatal aperture following incubation with abscisic acid, malate, or citrate. Furthermore, an effect on photosynthetic capacity was not observed in the mutant lines. However, leaf mitochondrial metabolism was affected in the plants. Levels of the intermediates of the tricarboxylic acid cycle were altered, and increases in both light and dark respiration were observed. We conclude that manipulation of the tonoplastic organic acid transporter impacted mitochondrial metabolism, while the overall stomatal and photosynthetic capacity were unaffected.
A consolidação do sistema de plantio direto no cerrado ainda encontra dificuldades quanto ao estabelecimento das plantas de cobertura. Nesse sentido, tem se optado pela técnica da sobressemeadura visando o aproveitamento da umidade no fim do período chuvoso. Entretanto, nem sempre há sucesso no estabelecimento das culturas com esse sistema de semeadura. Dessa forma, objetivou-se com este trabalho avaliar o desenvolvimento inicial de Urochloa ruziziensis em sobressemeadura no estágio R5.3 e desempenho agronômico da soja sob diferentes espaçamentos nas entrelinhas de cultivo. O trabalho foi conduzido a campo em Barra do Garças (MT) Brasil, na safra 2010/2011. O delineamento experimental foi o de blocos ao acaso, em esquema fatorial 5x2 com quatro repetições, caracterizado por cinco diferentes espaçamentos entrelinhas (0,40; 0,45; 0,50; 0,55 e 0,60 m) e dois cultivares de soja (P99R01 e M-Soy 9144RR). Foi avaliada a altura de plantas, número de vagens por planta, peso de mil grãos, número de plantas de U. ruziziensis aos 7, 14 e 21 dias após a emergência (DAE), índice de fechamento de linhas (IFL), radiação fotossinteticamente ativa (RFA) abaixo do dossel e RFA interceptada aos 30, 45, 60 e 75 DAE e produtividade de grãos. Independentemente do cultivar, os espaçamentos de 0,45 m a 0,50 m proporcionaram os maiores valores na altura de plantas, número de vagens por planta, número de plantas de U. ruziziensis e produtividade de grãos. Não houve efeito sobre o peso de mil grãos. Independentemente do cultivar, espaçamentos abaixo de 0,50 m proporcionaram os maiores IFL, maior interceptação da RFA e menor incidência da RFA abaixo do dossel.
Metabolic pathways and the key regulatory points thereof can be deduced using isotopically labelled substrates. One prerequisite is the accurate measurement of the labeling pattern of targeted metabolites. The subsequent estimation of metabolic fluxes following incubation in radiolabelled substrates has been extensively used. Radiolabelling is a sensitive approach and allows determination of total label uptake since the total radiolabel content is easy to detect. However, the incubation of cells, tissues or the whole plant in a stable isotope enriched environment and the use of either mass spectrometry or nuclear magnetic resonance techniques to determine label incorporation within specific metabolites offers the possibility to readily obtain metabolic information with higher resolution. It additionally also offers an important complement to other post-genomic strategies such as metabolite profiling providing insights into the regulation of the metabolic network and thus allowing a more thorough description of plant cellular function. Thus, although safety concerns mean that stable isotope feeding is generally preferred, the techniques are in truth highly complementary and application of both approaches in tandem currently probably provides the best route towards a comprehensive understanding of plant cellular metabolism.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.