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Objective This scoping review aims to identify and describe the methods used to collect and analyze dietary intake data in residents of Pacific Island countries. Introduction Dietary assessment explores associations between dietary factors and health outcomes. In regions, including the Pacific Islands, where diet-related, non-communicable diseases are increasing, this is a growing area of research. As this information is used to inform food and nutrition policies and practice, accurate collection, analysis, and interpretation of dietary assessment data relies on robust methods. A greater understanding of how nutrition studies are designed can strengthen the evidence on nutrition and health in Pacific Island settings and inform future research approaches. Inclusion criteria The scoping review will consider studies published in peer-reviewed journals, including quantitative and qualitative study designs and gray literature, including government reports, research and technical reports, theses and dissertations that measure and/or assess dietary intake in resident populations of the Pacific Island member countries of the Secretariat of the Pacific Community: American Samoa, Commonwealth of the Northern Mariana Islands, the Cook Islands, the Federated States of Micronesia, French Polynesia, Guam, the Independent State of Papua New Guinea, the Independent State of Samoa, the Kingdom of Tonga, New Caledonia, Niue, Pitcairn Islands, the Republic of Fiji, the Republic of Kiribati, the Republic of the Marshall Islands, the Republic of Nauru, the Republic of Palau, the Republic of Vanuatu, Solomon Islands, Tokelau, Tuvalu, and Wallis and Futuna. Methods There will be no time limit and searches will be conducted in PubMed, CINAHL, CABI, Scopus, Cochrane Library, and Web of Science. Results will be limited to English-language articles. Data will be extracted independently by two reviewers into a charting table. Results will be presented graphically and with tables accompanied by a narrative summary.

Our study assessed food access and availability in Auki, Solomon Islands by investigating the number, type and characteristics of food venues and characteristics of items for sale (including type, ...

Breadfruit (Artocarpus altilis) is primarily grown as a staple tree crop for food security in Oceania. Significant wind damage has driven interest in developing its dwarfing rootstocks. Due to the predominantly vegetative propagation of the species, grafting onto interspecific seedlings is an approach to identifying dwarfing rootstocks. However, grafting of breadfruit onto unrelated Artocarpus species has not been investigated. Here we first report the success of breadfruit grafting onto interspecific rootstocks, marang (A. odoratissimus) and pedalai (A. sericicarpus). To address the low graft survival, we investigated the relationship of plasma membrane (PM) H+ -ATPase activity to graft success. We provide the first evidence for a positive correlation between PM H+ -ATPase activity and graft survival. The graft unions of successful grafts had higher PM H+ -ATPase activity compared to those of failed grafts. Rootstocks with low PM H+ -ATPase activity in leaf microsomes before grafting had lower graft survival than those with high enzyme activity, with graft success of 10% versus 60% and 0% versus 30% for marang and pedalai rootstocks, respectively. There was a positive correlation between graft success and the PM H+ -ATPase activity measured from the rootstock stem microsomes 2 months after grafting [marang, r(7) = 0.9203, P = 0.0004; pedalai (r(7) = 0. 8820, P = 0.0017]. Removal of scion's own roots decreased the leaf PM H+ -ATPase activity of grafted plants regardless of the final graft outcome. Recovery of the enzyme activity was only found in the successful grafts. The function of PM H+ -ATPase in graft union development and graft success improvement is discussed.

Reducing horticultural postharvest loss is a priority in Samoa, due to declining agricultural productivity and wider dietary-based health concerns within the human population. Efforts to remediate loss is currently impeded by little information about the current levels of horticultural loss in Samoa or the factors contributing to this loss. In this study we quantified commercial postharvest loss of 23 horticultural crops at the Fugalei central municipal market on the Island of Upolu, Samoa, using direct weighing. Mean postharvest loss was further determined in all six municipal, community and private fruit and vegetable markets on the Samoan Islands of Upolu and Savai’i using vendor and farmer-trader surveys. Postharvest horticultural loss in the Fugalei municipal market was 6.2% (determined by weight) and 13.3% (based on vendor recall). There was no significant difference between mean postharvest loss in fruits compared to vegetables. The highest level of daily postharvest loss (5% to 22%) was observed for soursop, papaya, Tahitian lime, mustard cabbage and choko. Negligible loss (

Breadfruit (Artocarpus altilis) is a traditional staple tree crop in the Oceania. Susceptibility to tropical windstorm damage has driven an interest in developing breadfruit with dwarf stature. Gibberellin (GA) is one of the most important determinants of plant height and DELLA proteins are repressors of GA signalling pathway. As a first step toward understanding the molecular mechanism of growth regulation in the species, we isolated two full-length DELLA cDNAs, AaDELLA1 and AaDELLA2 from breadfruit. Sequence analysis indicated the deduced proteins encoded by these AaDELLAs bear all the hallmarks of functional DELLA of other species. Transcripts of AaDELLA1 and AaDELLA2 were detected in all plant organs, but the expression was much lower in flowers and fruits. AaDELLA1 showed predominantly higher expression in roots, but AaDELLA2 displayed higher expression in stems and leaves. Expression of both AaDELLAs was not significantly changed by exogenous GA3 treatment. Under paclobutrazol treatment, the expression of AaDELLA2 was up-regulated, but the expression of AaDELLA1 was not changed significantly. Treatments of high salinity up-regulated the expression levels of both AaDELLA1 and AaDELLA2. Treatment of drought stress increased the expression of AaDELLA2, but not that of AaDELLA1. The function of AaDELLAs is discussed with particular reference to their role in stem elongation and the opportunities of breadfruit dwarfing.

Here we discuss the novel application of handheld infrared thermal imagery as a learning tool to help smallholder farmers improve postharvest temperature management. Farmers in the Fiji Islands were trained in using a handheld thermal camera to view a series of on-farm demonstrations highlighting the consequence of poor postharvest practice. We observed that smallholder farmers accurately interpreted thermal imagery and the implication of poor practices. Our results showed thermal imagery has the potential to better communicate fundamental concepts of postharvest management. The availability of a range of iPhone, iPad, and Android platforms also means this technology can be widely accessible.

The Fiji Islands, like many small Pacific island nations, are thought to incur high rates of postharvest loss. Little work has been undertaken to quantify the amount of loss within Pacific horticultural value chains, or identify the key determinants. This study sought to quantify postharvest loss within Fijian smallholder tomato value chains and to examine the relative importance of current on-farm practices as possible contributors to this loss. A semi-structured survey of 115 smallholder tomato farmers in Sigatoka Valley and eastern Viti Levu was undertaken, covering socio-economic and demographic parameters, production and postharvest handling practice, and postharvest loss based on farmer recall. On-farm postharvest loss for smallholder farmer tomato value chains was between 26.1% in Sigatoka Valley and 27.6% in eastern Viti Levu. This finding was consistent with quantification of postharvest loss in Fijian tomato chains by direct determination, but is relatively high when compared to smallholder tomato value chain loss in Sub-Saharan Africa. When Fijian tomato value chains were segregated according to specific postharvest handling practice, the contributors to postharvest loss were often associated with on-farm decision-making. Those value chains that only harvested once a week, or in the early morning (before 7 am) or mid-day onwards, stored harvest product in the field for more than three hours, did not sort or grade prior to on-farm ripening, or used packing sheds that had relatively open designs, all had consistently higher levels of postharvest loss. The prevalence of specific postharvest handling practice in both locations is further reported. While this study highlights the impact of current on-farm postharvest handling practices on tomato value chain loss, what remain unclear are the underlying drivers associated with current postharvest handling behaviour and the decision-making that shapes quality and logistic control activities.

Ongoing dietary transitions in the Solomon Islands has resulted in an over-reliance on commercially sourced foods, leading to food insecurity, and a subsequent rise in multiple forms of malnutrition. The aim of this study was to investigate the individual dietary diversity and food preferences of the adult population living in Auki, Solomon Islands. A cross-sectional study involving 133 adults was undertaken in the Auki district via an interviewer-administered questionnaire. Individual dietary diversity scores (DDS) were determined based on the results of a 24-h recall method. Overall mean DDS was 7.27 (range 2&ndash, 12). Females and participants who lived outside the Auki town center had significantly higher dietary diversity scores. Low consumption of a variety of nutritious foods within food groups and high consumption of energy dense processed foods, indicates that diet quality is likely limited in some of this population. Participants desire for a diverse diet including local foods suggests that current dietary diversity status in this population may be influenced by food security rather than food preference.

Breadfruit (Artocarpus altilis) is a tropical fruit tree primarily grown as a staple crop for food security in Oceania. Significant wind damage has driven an interest in developing its dwarf phenotype. The presence of any dwarf breadfruit variety remains unknown. Little is known regarding the growth of the species on rootstocks. Here, we examined the phenotype of breadfruit plants growing on marang (Artocarpus odoratissimus) rootstocks within 18 months after grafting, we identified a rootstock-induced dwarf trait in the species. This dwarf phenotype was characterized by shorter stems, reduced stem thickness and fewer branches, with 73% shorter internode length, 51% fewer and 40% smaller leaves compared to standard size breadfruit plants. The height of breadfruit plants on marang rootstocks was reduced by 49% in 9 months, and 59% in 18 months after grafting. The results suggest marang rootstocks can be applied to breadfruit breeding program for tree vigor control. Further biochemical characterization showed plants on marang rootstocks displayed leaves without change of total chlorophyll content, but with lower total soluble sugars, and stems with reduced activity of plasma membrane H+-ATPase, a well-known primary proton pump essential for nutrient transport. The significance of the two parameters in rootstock dwarfing is discussed.

Resilience as a concept is often applied to address disaster risks and impacts. Metrics developed to measure the resilience of a community are often not applicable to other communities. In order for metrics to have utility and provide meaningful information to decision-makers, they need to be embedded within local contexts, be integrated across spatial scales, and address the community’s capacity for adaptation and transformation, in addition to coping. To this end, we present an innovative framework to assess subtle variations in levels of community resilience at the household, community, and regional scale. Using a case study approach, we demonstrate how local actors can apply the framework to derive an applicable suite of locally relevant indicators. The main limitation in applying this, and other participatory methods, relates to difficulties in obtaining a representative level of participatory engagement, restricting the credibility of results and success of subsequent strategies.

Postharvest handling systems in the South Pacific are often subject to poor on farm practices and inconsistent supply chain logistics. Previous studies have highlighted temperature management as particularly problematic. One challenge in seeking to improve handling practices and associated product quality is limited postharvest knowledge and capacity amongst supply chain participants. This paper outlines participatory research undertaken with smallholder farmers in Fiji and the Solomon Island to assess key postharvest thermal risk factors along four fruit and vegetable supply chains. In seeking to combine diagnostic and educational outcomes, a comparatively novel approach of using digital infrared thermal imaging, laser-point thermometer, micro-temperature sensors and reversible chromatic temperature labels was used to help farmers improve ambient postharvest temperature management. Hand-held infrared thermal imagery proved a useful tool in allowing smallholder farmers to visualise and then explore on-farm postharvest thermal risks factors. To provide farmers with ongoing means for self-assessment and potentially remediate postharvest temperature management practices, low-cost reversible chromatic temperature labels were provided. Adhesive chromatic temperature labels were particularly suited to smallholder farm application as they could be placed throughout the packing shed and on postharvest equipment.

Poor produce quality and inconsistent supply currently impede smallholder vegetable growers in Fiji from accessing high-value domestic markets. One proposed option to overcome these constraints is to adopt a more centralised approach to product grading and storage, based around a network of regional ripening and packaging facilities. In terms of tomato growers, this would necessitate reconfiguring existing postharvest supply chains, removing the need for on-farm ripening, and transport of harvest-green mature fruit. This preliminary study was undertaken to determine whether the alternative transport of mature hard-green fruit would affect the incidence of bruising and impact damage. Fruits of four ripening stages were commercially transported to Suva municipal market, and then stored for seven days at 20-28°C (ambient market storage conditions). Fruit deformation due to compression in the carton was significantly less in mature-hard green fruits. We found that mature hard-green stage was least susceptible to bruising (8%) compared with turning stage tomatoes (12%), commercially traded fruit (16%) and light-red (21%). For mature green tomatoes most damage (36%) was in the middle inner level of the carton. Light red and turning tomatoes placed in the bottom inside layer displayed highest level of damage, 62 and 46% respectively. Based on this preliminary trial, transporting hardgreen tomatoes is likely to reduce the risk of in-transit postharvest damage, compared to the current smallholder practices of transporting fully-ripe fruit.

Honiara&rsquo, s fresh horticultural markets are a critical component of the food distribution system in Guadalcanal, Solomon Islands. Most of the population that reside in Honiara are now dependent on the municipal horticultural market and a network of smaller road-side markets to source their fresh fruits and vegetables. Potentially poor postharvest supply chain practice could be leading to high levels of postharvest loss in Honiara markets, undermining domestic food security. This study reports on a preliminary assessment of postharvest horticultural market loss and associated supply chain logistics at the Honiara municipal market and five road-side markets on Guadalcanal Island. Using vendor recall to quantify loss, we surveyed a total of 198 vendors between November 2017 and March 2018. We found that postharvest loss in the Honiara municipal market was 7.9 to 9.5%, and that road-side markets incurred 2.6 to 7.0% loss. Based on mean postharvest market loss and the incidence of individual vendor loss, Honiara&rsquo, s road-side market system appears to be more effective in managing postharvest loss, compared to the municipal market. Postharvest loss was poorly correlated to transport distance, possibly due to the inter-island and remote intra-island chains avoiding high-perishable crops. Spatial mapping of postharvest loss highlighted a cohort of villages in the western and southern parts of the main horticultural production region (i.e., eastern Guadalcanal) with atypically high levels of postharvest loss. The potential importance of market-operations, packaging type, and mode of transport on postharvest market loss, is further discussed.

Breadfruit (Artocarpus altilis) is a traditional staple tree crop in the Oceania. Susceptibility to windstorm damage is a primary constraint on breadfruit cultivation. Significant tree loss due to intense tropical windstorm in the past decades has driven a widespread interest in developing breadfruit with dwarf stature. Gibberellin (GA) is one of the most important determinants of plant height. GA 2-oxidase is a key enzyme regulating the flux of GA through deactivating biologically active GAs in plants. As a first step toward understanding the molecular mechanism of growth regulation in the species, we isolated a cohort of four full-length GA2-oxidase cDNAs, AaGA2ox1- AaGA2ox4 from breadfruit. Sequence analysis indicated the deduced proteins encoded by these AaGA2oxs clustered together under the C19 GA2ox group. Transcripts of AaGA2ox1, AaGA2ox2 and AaGA2ox3 were detected in all plant organs, but exhibited highest level in source leaves and stems. In contrast, transcript of AaGA2ox4 was predominantly expressed in roots and flowers, and displayed very low expression in leaves and stems. AaGA2ox1, AaGA2ox2 and AaGA2ox3, but not AaGA2ox4 were subjected to GA feedback regulation where application of exogenous GA3 or gibberellin biosynthesis inhibitor, paclobutrazol was shown to manipulate the first internode elongation of breadfruit. Treatments of drought or high salinity increased the expression of AaGA2ox1, AaGA2ox2 and AaGA2ox4. But AaGA2ox3 was down-regulated under salt stress. The function of AaGA2oxs is discussed with particular reference to their role in stem elongation and involvement in abiotic stress response in breadfruit.

This paper reports on a detailed case study of postharvest losses along a commercial small holder tomato supply chain in Fiji. It is the first systematic quantification of postharvest horticultural losses undertaken in Fiji. Postharvest loss was measured from harvest through to product arrival at the Suva municipal fruit and vegetable markets, with post-municipal market loss determined using simulated storage conditions. In this study, 32.9% of the harvested product was removed from the commercial supply chain due to rots (8.8%), failure to ripen (8.9%), insufficient volume fill a carton (7.8%), physical damage during transport (0.1%) and fruit being over-ripe (6.4%). Poor temperature management during on-farm product ripening and limited on-farm postharvest hygiene were key contributors to the observed loss. In trace-back studies to identify the end-use of all product removed from the commercial chain, of the 32.9% total commercial postharvest loss, 11.0% was consumed at home and/or traded within the village, 6.3% was fed to domestic livestock, and a further 14.7% ended up as on-farm waste or dumped at the municipal refuge. Based on simulated ambient storage condition, once the fruit arrived at the municipal markets, daily postharvest loss thereafter was between 8.3% and 13.4%. Overall accumulative postharvest losses based on three days post-market ambient storage was 60.8%. Postharvest ripening, storage and transport conditions along the supply chain are discussed.

There is a clear association between food prices, affordability and issues of food security. Australian food supply chains have lengthened in recent years in response to consolidation policies of the dominant supermarkets, which have reduced the number of distribution centres in order to maximise economic efficiencies. This study presents a spatial analysis of a healthy food basket survey undertaken across Queensland, Australia in order to identify the primary determinants of food pricing. Ambiguity in the academic literature on this subject is largely due to limitations of the utilised methods. Our results indicate that food price variability is directly related to the type of store surveyed, and the distance of the surveyed store to the supermarket distribution centres in Brisbane, or urban centres on the east coast of Australia. Population size of towns and the level of social disadvantage observed in communities were indirect determinants of food prices. Therefore, in order to lessen the disadvantage already encountered by communities located in outer regional and remote areas who pay increasingly more for food than their urban counterparts, policy interventions need to move beyond subsiding food costs and consider the relationship between fuel prices and the lengthening of dominant food supply chains, in addition to the capacity of local supply chains.

Using a multi-disciplinary approach, this study quantifies horticultural postharvest losses of two medium-sized (annual pack volume 4500 t) commercial, domestic, tomato supply chains. Quantification of loss was based on weight or volume, consistent with direct measurement methods of the Food Loss and Waste Accounting and Reporting Standard 2016 and qualitative techniques were used to identify the drivers of the loss and contextualise the findings. Postharvest loss was found to be between 40.3% (55.34 t) and 55.9% (29.61 t) of the total harvestable product. It was determined that between 68.6% and 86.7% of undamaged, edible, harvested tomatoes were rejected as outgrades and consequently discarded due to product specifications. Between 71.2% and 84.1% of produced tomatoes were left in the field and not harvested. This study highlights significant factors contributing to high levels of food loss and waste. Edible products are being removed from the commercial food supply chain, rejected as outgrades deemed cosmetically defective due to market-based decisions. With only 44.1% and 59.7% of the harvestable crop reaching the consumers of the two supply chains, respectively, it is perhaps more appropriate to describe a food “waste” chain as opposed to a food “supply” chain.

Breadfruit [ Artocarpus altilis (Parkinson) Fosberg)] is a traditional staple crop grown for its starchy fruit throughout the tropics. It has long been recognized for its potential to alleviate hunger in the region. However, being a tree of 10 ‐ 30m, breadfruit is vulnerable to wind damage. Owing to the continuing trend of global climate change, the success of the species as a sustainable crop for delivering local food security is compromised by the likelihood of more intense tropical windstorms in the island nations. Tree height also forms a major constraint to disease management and fruit harvesting. These imperatives have driven an increasing interest in developing breadfruit varieties with short stature. While a great diversity of breadfruit cultivars with varying nutritional and agronomic characteristics exists, the genetic resource showing dwarfing traits is largely uncharacterised. Historically, there has been no intentional breeding for breadfruit cultivars. The long growth cycle, predominantly vegetative propagation and lack of genome information create challenge for crop improvement through traditional breeding. In this review, we highlight the current knowledge of plant dwarfism and its application in agricultural practices and genetic improvement for dwarf phenotype, and present options and tools for breadfruit dwarfing with special reference to natural genetic variability for dwarfing rootstocks, plant growth regulators, potential of mutagenesis and its combination with the currently

This paper outlines current postharvest handling practices of five vegetables supply chains in Viti Levu, the Fiji Islands. Domestic-orientated chains involved characteristically low-input production systems, had limited postharvest infrastructure (packing sheds, cool rooms and grading equipment) and reflected inadequate grower and trader postharvest handling knowledge and expertise. Domestic supply chains are often short, with poor and asymmetric communications, discontinuous transport logistics and ineffective postharvest disease-management the major contributors to postharvest losses. Paradoxically, while increasing farm size tended to reflect greater professionalism of production practices, this did not translate to concurrent improvements in postharvest handling. Export-orientated chains involve a much more structured approach to postharvest handling, based on trader and exporter-led interventions. Product consignments are sourced from a large number of growers, graded and packed in a central pack-house and held under cool storage prior to transport. Aspects of a quality management system are evident, with some traders also providing a support services to their contracted growers to improve product quality and supply uniformity.

Historically there has been limited institutional postharvest research, education and training in the South Pacific. In Fiji, Western Samoa and Tonga, of the three universities, four government ministries and one regional agency, that currently posses horticulture research, extension or training capacity, few have any dedicated postharvest specialists. While private-sector postharvest extension services do exist they are often fragmented and commonly limited to specific export-focused supply chains. In the last decade, increasing concerns about regional food security and a greater emphasis towards expanding horticultural trade and exports have resulted in significant investment in new postharvest infrastructure in the region. Since 2008, postharvest research infrastructure has been established in Western Samoa and in Tonga, coupled with ongoing donor assistance of private-sector postharvest-export infrastructure in Fiji. Unfortunately there has been desultory attention towards concurrently improving postharvest skills and training. This is of particular concern as it undermines the ultimate effectiveness of this investment, creating questionable sustainability. This paper reviews the current postharvest horticulture research and education capacity in the Pacific highlighting the key challenges and opportunities.

In the Pacific, horticulture quality management systems (QMS) are commonly driven by donor-funded interventions seeking poverty alleviation and food security derived outcomes. While the complexity of applying QMS to smallholder enterprises is well reported, the Pacific is particularly challenging due to the general supply chain dysfunction, cultural and social-based resistors that collectively erode entrepreneurism and commercial incentives, and a strong donor-dependence culture. Stakeholders, normally small-holder farmers and community-based enterprises tend to be asset limited, lack critical skills and knowledge, and operate in the absence of critical supply chain inputs. As a consequence, in spite of significant effort and resources having been applied to the development of Pacific QMS, there are few success stories. This disparity does not reflect a lack of market demand, in fact local tourism-based businesses actively seek QMS derived product, especially in the context of food quality and safety. Moreover, wider export trade is increasingly dependent on QMS to access and maintain market share. Workers in the field have increasingly accepted that early stakeholder engagement and empowerment are fundamental to successful QMS adoption. However, even with broad application of active participatory-based and market-driven approaches, Pacific QMS-based gains remain fragile and transient. This paper reviews two current enterprises in Fiji (Nature's Way Cooperative Limited and Joe's Farm Produce), with specific reference to their QMS adoption.

Pacific island countries face significant challenges in improving livelihoods and overcoming poverty, particularly with the food and fuel price surges in 2008, the impact of the global economic crisis, a number of natural disasters, difficulties maintaining infrastructure, and the negative effects of climate change. In addressing some of these challenges, Pacific island countries and international agencies recognise that improving the competitiveness of industries, which provide a platform for stronger economic growth, is the basis of overcoming many of these challenges. The importance of agricultural development in alleviating poverty and providing a catalyst for sustainable economic growth has been widely documented. In the Pacific, agricultural productivity tends to be derived from traditional small-holder farming systems, with horticultural production and associated supply chains representing one of the fastest growing components. Issues affecting the horticultural sector in the Pacific include distance from markets, small and inconsistent scale of production, high transport costs, eroding tariff preferences, technical market access barriers, migration of skilled labour, resource depletion and degradation, and risks from climate change. In meeting these challenges, a network of Australian universities and agencies, the Secretariat of Pacific Island Communities (SPC) and the University of the South Pacific, supported by ACIAR, have developed an innovative approach to horticultural development based around intervention priorities generated by supply chain and market analysis. Rather than pre-defining a specific set of commodities or researchable priorities the Pacific Agribusiness Research for Development Initiative (PARDI) incorporates a 'market-oriented' approach to identify horticulture products and chain opportunities. PARDI delivery has integrated horticultural scientists with social scientists and market analysts. This paper outlines the methodologies and preliminary project outcomes, with specific focus on horticulture development in Fiji, Vanuatu and the Solomon Islands.

Breadfruit (Artocarpus altilis) is a traditional staple tree crop throughout the tropics. Susceptibility to windstorm damage is the primary constraint on breadfruit cultivation. Significant tree loss due to intense tropical windstorm in the past decades has driven an increasing interest in developing dwarf varieties of breadfruit. As a first step toward understanding the molecular mechanism of growth regulation in the species, we investigated the role of gibberellin and the regulation of GA20-oxidase genes in breadfruit. We provided first evidence that the stem elongation in breadfruit could be manipulated by exogenous gibberellin-related growth regulators. We then cloned six GA20-oxidase cDNAs, AaGA20ox1–AaGA20ox6, in full length from breadfruit. Sequence analysis showed that the predicted proteins of the AaGA20ox1–AaGA20ox3 bear all the hallmarks of functional GA20-oxidase of other species, but predicted AaGA20ox4–AaGA20ox6 as expressed, unprocessed pseudogenes closely related to AaGA20ox2. AaGA20ox1, AaGA20ox3 and AaGA20ox4 were predominantly expressed in green vegetative organs, but displayed different expression pattern in roots and reproductive organs. AaGA20ox2, AaGA20ox5 and AaGA20ox6 were expressed mainly in leaves at low level. AaGA20ox1, AaGA20ox3–AaGA20ox6 were subjected to GA feedback regulation following treatment of exogenous gibberellin and/or gibberellin biosynthesis inhibitors. AaGA20ox1 and AaGA20ox3 were down-regulated under drought and salinity stress, but AaGA20ox2 was up-regulated under salt stress. Pseudogenes AaGA20ox4 and AaGA20ox5 were up-regulated under drought or/and salt stress condition. The function of AaGA20oxs is discussed with particular reference to their role in stem elongation and involvement in abiotic stress response in breadfruit.

Two genes encoding polyphenol oxidase (PPO) were isolated from pineapple (Ananas comosus[L.] Merr. cv. Smooth Cayenne). Sequence analyses showed that both contained a single intron and encoded typical chloroplast-localized PPO proteins, the sequences of which corresponded to two pineapple PPO cDNAs, PINPPO1 and PINPPO2, recently described by Stewart et al. (2001). Southern blot analyses suggested that pineapple contained only two PPO genes. Analysis of expression of PINPPO1 promoter GUS fusion constructs showed this promoter had a low basal activity and was cold- and wound-inducible, consistent with known mRNA expression profiles. Striking homologies to gibberellin response complexes (GARC) were observed in sequences of both the PINPPO1 and PINPPO2 promoters. Transient assays in mature pineapple fruit and stable expression in transgenic tobacco showed that PINPPO1 promoter-GUS fusions were indeed gibberellin (GA) responsive. A role for the element within the putative GARCs in mediating GA-responsiveness of the PINPPO1 promoter was confirmed by mutational analysis. PINPPO2 was also shown to be GA-responsive by RT-PCR analysis. Mutant PINPPO1 promoter-GUS fusion constructs, which were no longer GA-inducible, showed a delayed response to cold induction in pineapple fruit in transient assays, suggesting a role for GA in blackheart development. This was supported by observations that exogenous GA3 treatment induced blackheart in the absence of chilling. Sequences showing homology to GARCs are also present in some PPO promoters in tomato, suggesting that GA regulates PPO expression in diverse species.

The involvement of browning enzymes, polyphenoloxidase (PPO), peroxidase (POD) and phenylalanine ammonia-lyase (PAL) in blackheart development was investigated in pineapple fruit (Ananas comosus, Smooth Cayenne) following low temperature storage. An increase in PPO activity was related to the incidence of blackheart symptoms, both temporally and spatially. Fruit maturity significantly affected blackheart susceptibility; immature and over-mature fruits developed less blackheart injury than in ature fruit. The effect of maturity on blackheart susceptibility was highly correlated to the response of PPO activity to chilling. POD showed no significant change after chilling. Enhanced PAL activity was observed during chilling at 6, 13 and 18 degreesC. Chilling (6, 13 and 18 degreesC) also inhibited the increase of ascorbate peroxidase activity observed in the fruit stored continuously at 25 degreesC, but had less effect on catalase activity. The results indicate that the development of blackheart symptoms in pineapple fruit results from the disturbance of a number of metabolic processes that occur at sub-ambient temperatures. (C) 2002 Elsevier Science Ltd.. All rights reserved.

To study factors influencing the development of pineapple blackheart we are undertaking functional analyses of a polyphenol oxidase promoter whose expression is induced in blackheart affected tissues. Since transgenic pineapple fruit take three years to develop, such an analysis must be undertaken using transient assays. In this report we describe experiments aimed at optimising a transient assay system using biolistic DNA delivery in pineapple fruit. Two factors are shown to be critical, namely the use of unmethylated plasmid DNAs prepared using dam E. coli host strains, and the use of an internal standard to control for the inherent variability of transient expression assays.

Pineapple (Ananas comosus [L.] Merr.) fruit of variable cultivar ('Smooth Cayenne' and PRI hybrid '73-50') and maturity were stored at chilling temperatures to investigate the mechanism for blackheart inducement and development. When chilled for three weeks at 13degreesC followed by 7 days storage at 25degreesC, fruit of both cultivars developed significantly increased polyphenol oxidase (PPO) activities concurrently with blackheart symptoms. Fruit stored continuously at 25degreesC developed no blackheart. There was no correlation between peroxidase activity (POD) and blackheart development for either cultivar. The influence of fruit maturity on blackheart development was also investigated, by storing 'Smooth Cayenne' fruit of six maturity ranges for 3 weeks at 10degreesC, or for 3 weeks at 10degreesC followed by 7 days at 25degreesC. Immature fruit developed negligible blackheart, while fruit of mid-range maturity were susceptible, the latter also developed increased PPO activity after 4 weeks. Over mature fruit developed a translucent breakdown of the pulp, rather than blackheart. Differences in subsequent fruit susceptibility to blackheart were not consistent with PPO activities at harvest. Total phenol concentration increased with fruit maturity, but high phenol concentration was not consistent with increased blackheart incidence. There was no significant difference in ascorbic acid levels at harvest between the maturity ranges. The suggestion in the literature that ascorbic acid level at harvest indicates susceptibility to blackheart is not support by our data.

We are attempting to control blackheart by inhibiting expression of PPO in genetically engineered pineapple plants. PPO genes have been isolated from various pineapple tissues using PCR with redundant oligonucleotides and a cDNA which is specifically induced in blackheart affected fruit has been cloned. Suitable promoters to drive gene expression in pineapple have been defined and gene constructs suitable for transformation of the crop have been prepared. To generate transgenic pineapple we have established an efficient plant regeneration system based on the production of highly regenerable callus from leaf bases of tissue cultured plantlets. A transformation system based on micro-projectile bombardment of this regenerable callus has been developed. In addition, we have also transformed pineapple using Agrobacterium-mediated gene delivery to leaf bases, from which we have generated stably transformed plantlets. For biolistics we have obtained over a dozen independent transformation events in at least four separate experiments, transformation in some instances has been confirmed by Southerns and shoots have been regenerated from this material. For Agrobacterium, transformed plants have been regenerated and multiple events have been observed from at least four separate experiments.

The effects of detergents and mango sap on the development and anatomy of ‘etch’, a physiological skin disorder in mango (Mangifera indica L.) fruit, were examined. Etch was associated with a higher number of cracks in the cuticle than occurred in healthy tissue. Etch was induced on fruit dipped in the wetting agent Agral® at high concentrations (10, 50% v/v). Fruit kept in contact with pads saturated with low concentrations of detergents (Agral®, 0.1–1%; Amway LOC®, 0.1%) tended to develop etch at the perimeter of the contact area. Etch symptoms increased in severity with fruit ripening and increasing contact times with detergent. Lenticel spotting developed at lower detergent concentrations than were required for etch development. The oil, white oil/aqueous and blue lower aqueous components of mango sap were separated and applied to the skin of mangoes. No individual component resulted in more than mild perimeter etch. A 10:90 ratio of oil:aqueous fraction resulted in etch symptoms of moderate severity over the entire application area, but only when combined in wet contact with water or Agral®. The relevance of the results to mango postharvest handling systems is discussed.

Mature lemons (Citrus limon (L.) Burm. ‘Eureka') were subjected to increasing compression, impact and static loading, then stored at either 1C, 13C or 20C for 14 or 28 days. Following storage, fruit were assessed for cellular damage associated with the site of loading. Slow compression (1.7cm plunger driven at a loading rate of 200 mm min−1) resulted in cell damage in the mid to lower flavedo tissue. Tissue failure was characterised by cell rupture, with minor cell deformation and compression associated with damage to the oil glands. Impact loading caused relatively little lower flavedo damage, with most of the injury associated with the albedo, the upper flavedo and tissue surrounding the oil glands. Damaged albedo cells formed a distinct zone of ruptured and laterally compressed tissue which increased in area with drop height. Static loading (3.7 kg top weight) resulted in a similar mode of failure to that of impact loading, with extensive cellular damage observed in the lower albedo. Injury was distinct in that cells were not laterally compressed and flavedo damage was far more pronounced. While most of the tissue damage was directly

To determine the potential for fruit bagging to improve the quality of lychee, panicles on the northeast (NE), southeast (SE), southwest (SW) and northwest (NW), and at the top and bottom of the canopy of 12-year-old `Tai So' lychee trees, were enclosed in paper bags at early fruit set, at 1/2–3/4 fruit fill, and just before fruit colouring (corresponding to 80, 42 and 28 days before harvest). At commercial maturity, panicles from the NE and NW aspects and from the upper canopy had the greater number and mass of fruit per panicle, than panicles from the other parts of the canopy. Bagging had no significant (P

Vacuole represents a major storage organelle playing vital roles in pH homoeostasis and cellular detoxification. The chemical and functional properties of tonoplast in response to chilling temperature and their roles in chilling injury are largely unknown. In the current study, lipid composition of tonoplast and the activities of two vacuolar proton pumps, H+-ATPase (V-ATPase) and H+-pyrophosphatase (V-PPase), were investigated in accordance with the development of blackheart, a form of chilling injury in pineapple fruit (Ananas comosus). Chilling temperature at 10 °C for 1 week induced irreversible blackheart injury in concurrence with a substantial decrease in V-ATPase activity. By contrast, the activity was increased after 1 week at 25 °C. The activity of V-PPase was not changed under both temperatures. Level of total phospholipids of tonoplast decreased at 10 °C, but increased at 25 °C. There was no change at the level of total glycolipids under both temperatures. Thus, low temperature increased the ratio of total glycolipids vs. total phospholipids of tonoplast. Phosphatidylcholine and phosphatidylethanolamine were the predominant phospholipids of tonoplast. Low temperature increased the relative level of phosphatidic acid but decreased the percentage of both phosphatidylcholine and phosphatidylethanolamine. Unsaturated fatty acids accounted for over 60 % of the total tonoplast fatty acids, with C18:1 and C18:2 being predominant. Low temperature significantly decreased the percentage of C18:3. Modification of membrane lipid composition and its effect on the functional property of tonoplast at low temperature were discussed in correlation with their roles in the development of chilling injury in pineapple fruit.

Plasma membrane (PM) plays central role in triggering primary responses to chilling injury and sustaining cellular homeostasis. Characterising response of membrane lipids to low temperature can provide important information for identifying early causal factors contributing to chilling injury. To this end, PM lipid composition and ATPase activity were assessed in pineapple fruit (Ananas comosus) in relation to the effect of low temperature on the development of blackheart, a form of chilling injury. Chilling temperature at 10 °C induced blackheart development in concurrence with increase in electrolyte leakage. PM ATPase activity was decreased after 1 week at low temperature, followed by a further decrease after 2 weeks. The enzyme activity was not changed during 25 °C storage. Loss of total PM phospholipids was found during postharvest senescence, but more reduction was shown from storage at 10 °C. Phosphatidylcholine and phosphatidylethanolamine were the predominant PM phospholipid species. Low temperature increased the level of phosphatidic acid but decreased the level of phosphatidylinositol. Both phospholipid species were not changed during storage at 25 °C. Postharvest storage at both temperatures decreased the levels of C18:3 and C16:1, and increased level of C18:1. Low temperature decreased the level of C18:2 and increased the level of C14:0. Exogenous application of phosphatidic acid was found to inhibit the PM ATPase activity of pineapple fruit in vitro. Modification of membrane lipid composition and its effect on the functional property of plasma membrane at low temperature were discussed in correlation with their roles in blackheart development of pineapple fruit.

In accordance with the currently approved Australian citrus disinfestation protocol for export to Japan, degreened `Eureka' lemons [Citrus limon (L.) Burm.] were cold-stored for 2 weeks at 1C. Following cold treatment, fruit were stored at 5C for 3 weeks, then transferred to 20C for an additional week to simulate transportation and handling. Fruit harvested early in the season were more susceptible to chilling injury than fruit harvested later, with 62% having lesions >1 cm2 after 2 weeks at 1C. Most of the chilling injury occurred after subsequent storage (at 5C) rather than immediately after the 1C treatment. Injury was different from surface pitting or oleocellosis, manifesting as large uniform surface lesions 2 to 3 cm in diameter that rapidly discolored following storage at 20C. Although the oil glands were flattened, the collenchyma layer immediately above the oil gland remained intact. Cellular discoloration was localized around the oil gland, possibly indicating a lateral release of oil gland contents. Nondegreened late-season fruit developed substantially lower levels of chilling injury.

Lychee fruit are prone to postharvest desiccation, resulting in browning of the pericarp. Microscopic cracks (20–100 μm wide) in the pericarp surface were observed at harvest and had significantly increasing in density 12 h later. Microcracking extended through the sub-epidermal sclerenchyma layer into the mesocarp. Pericarp desiccation occurred prior to crack development, with cracking the result of dehydration rather than the initial cause. No evidence of cuticle thinning was observed prior to micro-cracking, however, localised cuticle deterioration on the protuberance did occur. We believe that initial pericarp desiccation may be the result of high permeability of the cuticle to water vapour, cuticle damage and the presence of lenticels. Although the cracking did not increase the rate of desiccation, micro-cracks may be important in both exposing the underlying anthocyanin-containing mesocarp tissue to further desiccation, and fungal penetration into the pericarp.

Polyphenol oxidase activity, anthocyanin concentration, endogenous ethylene production and anatomical features of mature lychee (Litchi chinensis Sonn.) pericarp were studied to understand better post-harvest tissue browning. Polyphenol oxidase (PPO) activity decreased significantly once fruit were harvested. Although anthocyanin degradation occurred, it was far slower than tissue browning. It is considered unlikely that pericarp browning is due to direct pigment degradation by polyphenol oxidase. Pericarp browning may in fact be caused by non-PPO mediated anthocyanin decolorization, coupled with localized PPO activity affecting secondary metabolites other than anthocyanin. Pericarp browning was correlated with moisture loss. The development of pericarp micro-cracking after harvest was observed, and may be involved in facilitating rapid pericarp moisture loss.

Development of lychee fruit (Litchi chinensis Sonn., cv. Kway May Pink) was studied from 21 to 103 days after anthesis, with specific emphasis on the pericarp. Pericarp structure was initially folded, with subsequent expansion closely associated with aril development. Cuticle thickness decreased from 8.75 |j,m to 1.88 μm at maturity, with micro-cracking of the pericarp surface observed 62 days after anthesis. Chlorophyll degradation and flavonoid production occurred simultaneously. Pericarp pH increased during ontogeny, and its possible interaction with pigment stability is discussed. Polyphenol oxidase activity decreased during fruit maturation, with peak activity prior to anthocyanin production. The L-ascorbic acid content of the pericarp decreased throughout development.

Marketing of immature fruit has had a major impact on the Lychee Industry in Queensland. Trials to develop a practical maturity standard have highlighted the utility of the Brix:acid ratio of the pulp. Cultivar variability, growing region and seasonality have all been assessed and shown to have a significant (P>0.05) although minimal effect. Correlation to mean eating quality is consistently high (R2 = 0.75). A recommendation of a Brix:acid ratio of 30 to 40 (calculated to give EQ 5 to 6) will be made to industry for the 1989/90 Queensland Lychee Season.

Two genes encoding polyphenol oxidase (PPO) were isolated from pineapple (Ananas comosus[L.] Merr. cv. Smooth Cayenne). Sequence analyses showed that both contained a single intron and encoded typical chloroplast-localized PPO proteins, the sequences of which corresponded to two pineapple PPO cDNAs, PINPPO1 and PINPPO2, recently described by Stewart et al. (2001). Southern blot analyses suggested that pineapple contained only two PPO genes. Analysis of expression of PINPPO1 promoter GUS fusion constructs showed this promoter had a low basal activity and was cold- and wound-inducible, consistent with known mRNA expression profiles. Striking homologies to gibberellin response complexes (GARC) were observed in sequences of both the PINPPO1 and PINPPO2 promoters. Transient assays in mature pineapple fruit and stable expression in transgenic tobacco showed that PINPPO1 promoter-GUS fusions were indeed gibberellin (GA) responsive. A role for the element within the putative GARCs in mediating GA-responsiveness of the PINPPO1 promoter was confirmed by mutational analysis. PINPPO2 was also shown to be GA-responsive by RT-PCR analysis. Mutant PINPPO1 promoter-GUS fusion constructs, which were no longer GA-inducible, showed a delayed response to cold induction in pineapple fruit in transient assays, suggesting a role for GA in blackheart development. This was supported by observations that exogenous GA(3) treatment induced blackheart in the absence of chilling. Sequences showing homology to GARCs are also present in some PPO promoters in tomato, suggesting that GA regulates PPO expression in diverse species.