The role of ethylene in kiwifruit ripening and senescence

Purpose of review: Kiwifruit cv. 'Hayward' is considered a fruit with typical climacteric behaviour. Healthy fruit display climacteric behaviour at ambient temperature (∼20°C) and non-climacteric behaviour at temperatures ≤10°C. However, it is extremely sensitive to ethylene action even at low temperatures. The behaviour of kiwifruit in relation to ethylene sensitivity and ethylene production is of great importance for long-term storage. This paper discusses the most recent findings concerning the role of ethylene in kiwifruit ripening and senescence. Main findings: Kiwifruit senses propylene at temperatures ranging from 15 to 34°C by advancing the onset of ripening and respiration, while the ethylene burst occurs late in the ripening process. The main reason for late ethylene production is the tardy increase of 1-aminocyclopropane-1-carboxylate synthase (ACCS) activity. The lag period for ethylene production decreases as temperature increases. Propylene-treated kiwifruit show reduced ethylene production at 38°C and almost none at 40°C. 1-Aminocyclopropane-1-carboxylate oxidase (ACCO) is the first enzyme to be affected at high temperatures, followed by ACCS. Below a critical temperature range (11-14.5°C), kiwifruit lacks the ability to produce ethylene even when treated with propylene. The main reasons for the inhibition of ethylene production at 10°C are primarily due to the suppression of the propylene-induced ACCS gene expression and low ACCO activity. However, wounded or Botrytis-infected fruits produce ethylene at low temperatures. A period of about 12 days at low temperature induces autocatalysis of ethylene upon re-warming of kiwifruit, while around 19 days are required when fruit is held continuously at ambient temperatures. Low temperatures slow ripening, while high temperatures block or cause abnormal ripening. Controlled atmosphere (CA) storage in 2% O2 + 5% CO2 and ultra low oxygen (ULO) storage with 1% O2 + 1% CO2 increases storage life compared with conventional storage (CS). Prolonged storage for 60 days at 0°C induces ACCS activity but not that of ACCO. Upon re-warming, only fruit stored under CS and CA produced ethylene. ULO-treated fruit lost the ability to produce ethylene, mostly due to reduced ACCO activity. Directions for future research: The atypical behaviour of kiwifruit in relation to ethylene sensitivity and ethylene production at different temperatures and atmosphere compositions makes this fruit a good system for studying the ethylene biosynthetic pathway, and its regulation and action on fruit ripening and senescence. Although some efforts have been made to clarify this behaviour at the physiological level, the means by which the genes of the enzymes of ethylene biosynthesis pathway are regulated in kiwifruit need further research. © 2007 Stewart Postharvest Solutions (UK) Ltd

Spatial Distribution of Qualitative Characteristics and Production Factors of Kiwifruit at "Beira Litoral", Portugal

Objective of the present research was to generate information about the evolution of production factors and qualitative characteristics of 100 geo-referenced orchards of Beira Litoral-Portugal during three consecutive years. Graphical interpretation of quantitative and qualitative characteristics of kiwifruit production was done using GIS, geostatistics. Maps of biophysical characteristics of the region were then related to the areas of higher production and quality and it was studied their evolution over time. Those maps help to make decisions about harvesting time or localized correction of production factors and to choose the adequate location for vineyard installation in the region. Despite our enthusiasm for this technology, we are not proposing that it is a solution to all crop management problems or that it is appropriate for every operation. Meanwhile, we believe that the use of GIS and geostatistics provides a tool for sustainable production

Sustainable postharvest handling of horticultural products

Sustainable commercial horticultural success depends on satisfying consumer requirements. Fresh fruits and vegetables are important components of human food. However, horticultural products are highly perishable and losses can be of great importance if postharvest correct measures are not provided. Quality of fresh horticultural products can not be improved by postharvest technologies, only can be maintained, what means horticultural products must be of high quality at harvest. There is a worldwide trend to explore new alternatives to increase storage life, giving priority to methods that reduce horticultural product decay avoiding negative effects to human health and environment. The objective of our research was to apply environmental and human health friendly techniques to preserve fresh fruit quality through storage. Figs, apricots, oranges, pomegranates and kiwifruits were treated with sodium bicarbonate, calcium chloride, acetic acid or subjected to modified atmosphere packaging to increase their storage life with minimal quality loss, as well as damage to human health and environment. The use of these treatments and techniques gave a great performance in the reduction of fruit losses, weight loss and fruit softening. Postharvest techniques such as modified atmosphere and calcium, sodium bicarbonate and acetic acid treatments, when applied in adequate concentrations, help to keep fruit quality through storage, without damaging the environment and human health. The benefit of each treatment depends on the type of fruit

Biochemical basis of thermoregulation and autocatalytic ethylene production in ripening of kiwifruit cv. Hayward

Tese de Doutoramento, Produção Vegetal, Unidade de Ciências e Tecnologias Agrárias, Universidade do Algarve, 1999O kiwi (Acíinidia deliciosa A. Chev.) tem sido considerado um fruto climatérico. No entanto, este fruto comporta-se atipicamente em resposta à aplicação externa de etileno a várias temperaturas. A incapacidade do kiwi para produzir etileno a baixas temperaturas, a produção de etileno à temperatura ambiente após um período de frio. o limite máximo de temperatura para produção de etileno e o seu comportamento pósarmazenamento não estão suficientemente estudados. Nesta tese investigaram-se algumas características particulares do percurso da biossíntese do etileno e o amadurecimento do kiwi induzidos por propileno a temperaturas de 10 a 45ºC, após armazenamento a baixas temperaturas, assim como após armazenamento em atmosfera controlada (CA) e nível de oxigénio ultra baixo (ULO).Kiwifruit (Acíinidia deliciosa A. Chcv.) is considcrcd a climactcric fruit. However, it bchaves atypically in response to externai ethylene application at different temperaturcs. The lack of ability of the kiwifruit to produce ethylene at low temperatures, its chilling requirements and maximum temperalure limil for ethylene production and its behaviour post-storagc are poorly understood. In this thesis were studied some particular features of the ethylene biosynthesis pathway and ripening of kiwifruit induced by propylene at temperatures from 10 to 45ºC, during shelf-life after chilling, as well as after storage in controlled atmosphere (CA) and ultra low oxygen (ULO) conditions

The effect of hydrogen cyanamide on bud break and yield of kiwifruit in Northwest-Portugal

Kiwifruit (Actinidia deliciosa cv. Hayward) was introduced into Northwest Portugal at the early 1970's increasing its importance up to date. The main objective of orchard management is to find out the cultural techniques suitable for the region, in order to obtain good yield and quality fruit. Winter chilling (less than or equal to7.2degreesC) plays a significant role in kiwifruit break dormancy. Insufficient chilling can be countered by chemical agents as hydrogen cyanamid (Dormex). The objective of this research was to quantify the efficiency of hydrogen cyanamide (0%, 4%, and 6%) on bud break dormancy and yield and fruit quality. Experiments were carried out over two years on a mature 'Hayward' kiwifruit orchard. The results showed that 4% Dormex was the most efficient in increasing marketable yield due to increase of flower bud formation and higher level of fruit set. There were no significant differences among treatments in soluble solids content, flesh firmness and dry weight. Titrable acidity showed higher values with increased Dormex concentration

Pomegranate (Punica granatum L.): A medicinal plant with myriad biological properties - A short review

The pomegranate, Punica granatum L., which can be found throughout the Mediterranean region, in Southeast Asia, California and Arizona in USA was in ancient times referred as possessing powers of fertility, abundance and good luck (fruit). The biological properties of extracts (antimicrobial, antioxidant, anticancer, anti-inflammatory, among other properties) obtained from several parts of pomegranate is reported in the present work. Due to such properties, the extracts have been used in therapeutics, such as in the prevention of infection, inflammation, cancer, among other applications. However, other aspects are also referred in the present work such as the good practices of culture and fruit preservation, search of new compounds, selection of cultivars through biotechnological techniques for obtaining juice or fruits ready to eat. Such compilation of information was based on the search in the ISI Web of Knowledge (Thomson Reuters) from 2009 up to the beginning of October 2010

Postharvest handling of horticultural products

Fruit and vegetables are in a live state after harvest. Continued respiration results in carbon dioxide production, moisture, and heat, which influence the storage environment, packaging, and refrigeration requirements. A current knowledge of good practices for the harvest and postharvest handling of fresh horticultural products is fundamental due to their high perishability [1,2]. It is estimated that 30% of produced horticultural commodities are lost in the process between harvest and consumption [3]. The reduction in these losses is imperative nowadays, because it will impact back the amount of produced food, with benefits on agricultural inputs, water and land use, contributing to the sustainability of agriculture and the planet.info:eu-repo/semantics/publishedVersio

Changes in the chemical parameters during the production of água-mel from Portugal

Agua-mel is a honey-based traditional product typically produced in southern Portugal. The evolution of some parameters during its production using two distinct containers (aluminium and stainless steel with a water cooling system) and two heating sources (gas heating and electricity) were evaluated. All parameters, except moisture, increased over time, reaching a 'plateau' after 8 h of heating. Moisture, free acidity, HMF (hydroxymethylfurfural), colour, melanoidins, phenols and glucose depended on the producer and procedure for obtaining agua-mel. Kinetic parameters and correlation coefficients were determined. In general, changes in parameters during agua-mel production followed zero- and/or first-order kinetics, depending on the producer and heating system.Fundacao para a Ciencia e a Tecnologia; Ministerio da Agricultura, Mar, Ambiente e Ordenamento do Territorio (Portugal) [Programa Apicola Nacional] - Medida 6Ainfo:eu-repo/semantics/publishedVersio

Movimentos públicos e memórias privadas silêncios e discursos da guerra civil espanhola

This article reflects upon the process of "recuperation of the historical memory" of the II Republic and the Spanish Civil War, in the construction of a contra-hegemonic memory of the dictatorship, and the preservation of the "apolitical speech" on the part of the individuals oppressed during the Civil War and the Franquist regime. In the way to understand the problematic between the public movements of the associations, and the individuals' private memories, we establish a diachronic perspective between past and present, choosing as case study the events occurred in Oliva de la Frontera, and its social representations in the ethnographic present.Este artigo reflecte sobre o processo de "recuperação da memória histórica" da II Republica e da guerra civil de Espanha, na construção de uma memória contra hegemónica da ditadura, e sobre a preservação do "discurso apolítico" por parte de indivíduos represaliados da guerra e do regime franquista. No sentido de compreendermos as problemáticas entre os movimentos públicos das associações e as memórias privadas dos indivíduos, estabelecemos uma perspectiva diacrónica entre passado e presente, elegendo como estudo de caso os acontecimentos ocorridos na localidade estremenha de Oliva de la Frontera e as suas representações sociais no presente etnográfico

Edible coatings enriched with essential oils on apples impair the survival of bacterial pathogens through a simulated gastrointestinal system

Edible coatings supplemented with essential oil components have been investigated to control spoilage microorganisms. In this study, the survival of Listeria monocytogenes and Salmonella enterica serovar Typhimurium on apples treated with edible coatings based on sodium alginate (2%) (ECs) and supplemented with essential oil components, namely eugenol (Eug) at 0.2% or in combination with 0.1% (v/v) of Eug and citral (Cit) at 0.15% was determined. Both bacterial pathogens were exposed on apples treated with ECs supplemented with Eug or Eug + Cit and challenged with gastrointestinal fluids and their survival was examined. Both pathogens were able to survive on the surface of 'Bravo de Esmolfe' apple. The use of ECs in fresh-cut fruits impaired the survival of both bacterial populations over 72 h at 4 °C. The exposure of the pathogens on apples with ECs supplemented with Eug and Cit and challenged with gastrointestinal fluids significantly reduced their survival. This study evidences that the use of alginate edible coating enriched with Eug or the combination of Eug and Cit can contribute to the safer consumption of minimally processed fruits.Fundacao para a Ciencia e a Tecnologia (FCT) UID/BIM/04773/2013 CBMRinfo:eu-repo/semantics/publishedVersio