Browsing by Author "Rodrigues, Ana Cristina"
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- Cold storage demand for 'Rocha' pear ripening: a comparison between a shorter and longer cold periodPublication . Dias, Cindy; Ribeiro, Tânia; Rodrigues, Ana Cristina; Ferrante, António; Vasconcelos, Marta W.; Pintado, Manuela'Rocha' pear is a cultivar that when harvested at the recommended maturity stage (physiological condition that allows resisting to prolong cold storage), requires chilling exposure after harvest, to induce an autonomously ripening appreciated by the consumer. Fruit were stored immediately after harvest, for 6 d (batch 1) or 26 d (batch 2), in normal cold atmosphere storage, to further our understanding of 'Rocha' pear ripening under different short cold storage durations. The ripening events were then monitored at 0, 3, 7, and 10 d of shelf-life at room temperature (± 20 °C) through physicochemical and biochemical changes, including firmness, soluble sugars, malic acid, esters profile, and ethylene metabolism (1-aminocyclopropane-1-carboxylic acid (ACC) and 1-aminocyclopropane-1-carboxylic acid oxidase (ACO)). We found that ripening behaviour upon rewarming from both cold storage periods was similar, with fruit ripening with a typical pattern of ethylene production and respiration rates concomitant with a higher ACO activity. Soluble sugar and esters emission were not influenced by cold storage duration, but interestingly butyl acetate levels were significantly higher on pear, which was cold stored for 26 d Our data provide more novel information about Rocha' pear's ripening physiology, indicating for the first time that approximately one week of chilling temperature is enough to promote ripening rate processes. Such knowledge could be an asset to the efficient management of 'Rocha' pear storage.
- Effect of naphthaleneacetic acid on restoring ‘Rocha’ pear ripening under 1-MCP evergreen effectPublication . Dias, Cindy; Ribeiro, Tânia; Rodrigues, Ana Cristina; Ferrante, António; Vasconcelos, Marta; Pintado, Manuela
- Effect of naphthaleneacetic acid on restoring ‘Rocha’ pear ripening under 1-MCP evergreen effectPublication . Dias, Cindy; Ribeiro, Tânia; Rodrigues, Ana Cristina; Ferrante, António; Vasconcelos, Marta W.; Pintado, Manuela'Rocha’ pear (Pyrus communis L. cv. Rocha), a DOP cultivar from the west region of Portugal, is quite appreciated worldwide due to its exceptional organoleptic quality. Because of its high exportation, preservation of this cultivar during long-term cold storage is of utmost importance, but remains a challenge for suppliers, especially after diphenylamine exclusion from the agricultural sector. Since then, postharvest disorders have been prevented through the use of 1-methylcyclopropene (1-MCP). Nevertheless, this compound disrupts the normal ripening of fruit, affecting its eating quality and producer’s sustainability. Consequently, there is the need for developing innovative solutions to recover ‘Rocha’ pear ripening capacity after 1-MCP application. Several strategies have been investigated to avoid the persistent blockage of ripening after 1-MCP as, for example, the application exogenous ethylene, the increase of temperature, but demand high energy consumption. This study was designed to test the restorage of ripening via immersion of 1-MCP treated fruits in an auxin- 1-Naphthaleneacetic acid (1-NAA) solution. Fruit ripening as judged by ethylene evolution and respiration associated with color changes and softening, was accelerated by 1-NAA treatment compared to control (pear only treated with 1-MCP). 1-NAA treatment effect was evident through the firmness loss of the fruit (ca. 60%) and increased internal ethylene production (ca. 50%). Also, exogenous 1-NAA treatment increased 1-aminocyclopropane carboxylic acid and ACC oxidase activity corroborating the physiological results obtained. The results provide information regarding how 1-MCP blockage may be circumvented, thus opening avenues for consistent ripening of ‘Rocha’ pear ensuring fruit quality and reducing postharvest losses.
- Estratégias de recuperação do amadurecimento da pera ‘Rocha’ tratada com 1-MCP no pós-armazenamentoPublication . Dias, Cindy; Rodrigues, Ana Cristina; Ribeiro, Tânia; Bonifácio, Teresa; Gómez-García, Ricardo; Ferrante, Antonio; Vasconcelos, Marta; Pintado, ManuelaA pera ‘Rocha’ (Pyrus communis ‘Rocha’) do Oeste DOP é uma variedade portuguesa. Com o aumento da capacidade produtiva e das exportações, surgiu a necessidade de adotar estratégias de armazenamento que permitam a disponibilidade deste fruto durante cerca de 10 meses. Em combinação com a refrigeração e atmosfera controlada, a aplicação do 1-MCP tem sido uma das técnicas mais usadas para prolongar o armazenamento da pera ‘Rocha’ e prevenir o aparecimento de escaldão superficial. No entanto, as centrais fruteiras debatem-se com o problema associado à utilização do 1-MCP, um antagonista da síntese do etileno, que impede o amadurecimento normal do fruto, afetando a qualidade final ao nível do consumidor. O presente trabalho teve como objetivo avaliar o impacto de diferentes estratégias (físicas e químicas) nas características físico-químicas e fisiológicas da pera ‘Rocha’ após a aplicação do 1-MCP. Para tal, peras conservadas com 1-MCP foram expostas a fatores isolados nas câmaras como a temperatura, o etileno exógeno, a elevação da % de CO2, a aplicação de hormonas vegetais (ácido naftalenoacético) ou combinação destes fatores. Durante o tempo de prateleira (7 dias à temperatura ambiente) foi feita a monitorização da produção de etileno e compostos aromáticos, da taxa de respiração e dos principais parâmetros físico-químicos dos frutos – cor da epiderme, firmeza da polpa, índice refratométrico e acidez titulável. Além disso, foi avaliada a capacidade das estratégias em induzir a atividade das enzimas envolvidas na biossíntese do etileno e a expressão de genes de regulação do metabolismo do etileno. Os frutos expostos à combinação de etileno ou CO2 com um incremento da temperatura (-0.5 C para 10 C) e ao ácido naftalenoacético evidenciaram aumentos na respiração e na produção de etileno após o tempo de prateleira e em comparação com os frutos apenas tratados com 1-MCP. Relativamente à firmeza da polpa, também se verificou uma perda significativa nos frutos sob algumas condições referidas, acompanhada por uma maior produção de etanol e acetatos no perfil aromático destes frutos. De uma forma geral, não se verificaram grandes impactos das estratégias na cor e índice refratométrico. Particularmente, o tratamento dos frutos com a auxina também possibilitou o aumento da atividade das enzimas envolvidas na síntese de etileno. Além disso, estas estratégias permitiram induzir a expressão de genes que codificam recetores de etileno e das enzimas da biossíntese do etileno. Os resultados obtidos evidenciam o potencial do incremento na temperatura e o tratamento com auxina em ultrapassar a limitação do uso do 1-MCP na reativação do amadurecimento da pera ‘Rocha’.
- Improving the ripening process after 1-MCP application: implications and strategiesPublication . Dias, Cindy; Ribeiro, Tânia; Rodrigues, Ana Cristina; Ferrante, António; Vasconcelos, Marta W.; Pintado, ManuelaBackground: Consumers’ lifestyles demand high-quality products, requesting adequate fruit storage. Management of ethylene production is of paramount importance when planning postharvest storage, since this phytohormone is the key molecule behind the ripening and senescence process. Cold storage combined with 1-MCP has been one of the most applied postharvest treatments to extend the shelf-life of several fruit. However, 1-MCP is a potent inhibitor of ethylene action, leading frequently to the blockage of ripening denominated as ‘evergreen’ effect. Scope and approach: Ethylene biosynthesis and perception pathway are described, as well as a critical review on 1-MCP inhibitory mechanisms. Technologies used to induce postharvest ripening after 1-MCP application are described with special attention to the latest and most significant published works. The most relevant 1-MCP reversion strategies are discussed, aiming to develop more innovative and effective approaches for stimulating ripening. Finally, the importance of tailoring treatments to specific cultivars is discussed, using pear as a case study. Key findings and conclusions: Optimizing temperature and applying exogenous ethylene have been the main methods to reverse the effect of 1-MCP. Also, treatment with other phytohormones has shown promising results. However, the strategies effectiveness is dependent on the cultivar, time of application, and concentration of the applied compound. Also, since 1-MCP binds irreversibly to the ethylene receptor, the biosynthesis of new receptors may reverse the ‘evergreen’ behaviour. Therefore, attempts should be made to develop strategies according to each cultivar and their capacity to stimulate the expression of ethylene genes both related to its biosynthesis and perception.
- Relationship between minerals and physicochemical parameters with fruit quality in ‘Rocha’ pear orchardsPublication . Dias, Cindy; Ribeiro, Tânia; Rodrigues, Ana Cristina; Vasconcelos, Marta W.; Ferrante, Antonio; Pintado, ManuelaAims: At the same location, variability among orchards may be high, which is reflected in fruit quality, and it may be associated mainly with growers’ practices. This study aimed to identify physicochemical variability within pears (Pyrus communis L. cv 'Rocha') from three orchards from the same location and under the same climate conditions and correlate it with mineral composition. Methods: Fruits from three orchards harvested at the optimal harvest time were characterized during ripening under shelf-life conditions of 7 d at 20 ± 2 °C. The analyses performed included ethylene production, respiration rate, fruit quality (firmness, skin colour, soluble solids, and titratable acidity), macro and micronutrients, ethylene biosynthesis enzymes, esters, sugars, and organic acids. Principal component analysis was used to show the variability among fruits from the three orchards and to correlate the differences with the fruit mineral composition. Results: Phosphorus (P) and potassium (K) were significantly correlated with esters and soluble solids content (r ∼0.4 for both minerals). Fruits with higher P and K concentrations were associated with a potential over-ripeness pattern considering their higher acetate production and lower sugar concentration. Esters, soluble sugars, and sorbitol were the dominant fruit quality factors responsible for the differences among the orchards.Conclusion: With this study it is expected that a better understanding of the relationship between specific minerals and quality parameters can help growers manage their orchards more efficiently and achieve consumers’ quality demands.
- Restoring 'Rocha' pear ripening under 1-MCP evergreen effect: a comparison between normal ripening and after auxin treatmentPublication . Dias, Cindy; Ribeiro, Tânia; Rodrigues, Ana Cristina; Ferrante, António; Vasconcelos, Marta W.; Pintado, Manuela‘Rocha’ pear (Pyrus communis L. cv. Rocha) is a DOP cultivar, from West region of Portugal, appreciated worldwide due to its exceptional organoleptic and nutritional quality [1-2]. It´s high exportation has raised the need to develop adequate conditions for long-term cold storage. For about forty years, the postharvest application of diphenylamine was an efficient strategy used to protect fruit from postharvest problems. However, in 2011 its use was prohibited. Nowadays, in combination with cold storage, 1-MCP has been one of the most applied techniques to extend the storage of ‘Rocha’ pear. However, fruit industry is facing a problem resulting from 1-MCP application which compromise producers’ sustainability, because 1-MCP disrupts the normal process of ripening, denominated as “evergreen” effect, affecting the quality of ‘Rocha’ pear and increasing postharvest losses [3–4]. In this study, we have tested the restoring of ripening via exposure of 1-MCP treated fruits to an auxin. Time course physiological and biochemical analysis comparison with ‘Rocha’ pear normal ripening, revealed that ripening induction by the auxin treatment, after 1-MCP, is evident from around 60 % of fruit firmness loss and around 50 % increased internal ethylene production. Exogenous auxin treatment increased of 1-aminocyclopropane carboxylic acid (ACC) and malonyl-ACC (MACC) levels, ACC synthase (ACS) and ACC oxidase (ACO) activity and enhanced the pear fruit ripening. The results provide information regarding how blockage caused by 1-MCP may be circumvented, thus opening avenues for consistent ripening of ‘Rocha’ pear.
- Restoring 'Rocha' pear ripening under 1-MCP evergreen effect: a comparison between normal ripening and after auxin treatmentPublication . Dias, Cindy; Ribeiro, Tânia; Rodrigues, Ana Cristina; Vasconcelos, Marta W.; Ferrante, António; Pintado, Manuela
- Restoring 'Rocha' pear's ripening capacity under 1-MCP evergreen effect: the role of temperature and ethylene treatmentPublication . Dias, Cindy; Ribeiro, Tânia; Rodrigues, Ana Cristina; Vasconcelos, Marta W.; Ferrante, António; Pintado, Manuela
- 'Rocha' pear mineral composition relation with quality traitsPublication . Dias, Cindy; Rodrigues, Ana Cristina; Vasconcelos, Marta W.; Ferrante, António; Pintado, Manuela