88 resultados para Pears


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Report commissioned by the Pharmaceutical Society of Ireland.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: The capacity of European pear fruit (Pyrus communis L.) to ripen after harvest develops during the final stages of growth on the tree. The objective of this study was to characterize changes in 'Bartlett' pear fruit physico-chemical properties and transcription profiles during fruit maturation leading to attainment of ripening capacity. Results: The softening response of pear fruit held for 14days at 20°C after harvest depended on their maturity. We identified four maturity stages: S1-failed to soften and S2- displayed partial softening (with or without ET-ethylene treatment); S3 - able to soften following ET; and S4 - able to soften without ET. Illumina sequencing and Trinity assembly generated 68,010 unigenes (mean length of 911bp), of which 32.8% were annotated to the RefSeq plant database. Higher numbers of differentially expressed transcripts were recorded in the S3-S4 and S1-S2 transitions (2805 and 2505 unigenes, respectively) than in the S2-S3 transition (2037 unigenes). High expression of genes putatively encoding pectin degradation enzymes in the S1-S2 transition suggests pectic oligomers may be involved as early signals triggering the transition to responsiveness to ethylene in pear fruit. Moreover, the co-expression of these genes with Exps (Expansins) suggests their collaboration in modifying cell wall polysaccharide networks that are required for fruit growth. K-means cluster analysis revealed that auxin signaling associated transcripts were enriched in cluster K6 that showed the highest gene expression at S3. AP2/EREBP (APETALA 2/ethylene response element binding protein) and bHLH (basic helix-loop-helix) transcripts were enriched in all three transition S1-S2, S2-S3, and S3-S4. Several members of Aux/IAA (Auxin/indole-3-acetic acid), ARF (Auxin response factors), and WRKY appeared to play an important role in orchestrating the S2-S3 transition. Conclusions: We identified maturity stages associated with the development of ripening capacity in 'Bartlett' pear, and described the transcription profile of fruit at these stages. Our findings suggest that auxin is essential in regulating the transition of pear fruit from being ethylene-unresponsive (S2) to ethylene-responsive (S3), resulting in fruit softening. The transcriptome will be helpful for future studies about specific developmental pathways regulating the transition to ripening. © 2015 Nham et al.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Internal browning is an important disorder in pear fruit which can lead to economic losses. Pears (Pyrus communis L. cv. Bartlett) were harvested at early harvest maturity of 90 N from a commercial orchard in southern Brazil. Methyl jasmonate, ethanol, and 1-methylcyclopropene vapor treatments were carried out for 24 hours in order to mitigate the internal browning disorder. Fruit were stored for up to 150 days at 0 ± 1 °C and 90 ± 5 % RH. Pears exhibited internal browning in 37 % of the control samples after 90 days of cold storage. However, no internal browning symptoms were observed in the 1-MCP treatment. The first symptoms in 1-MCP samples were noticed after 120 days of cold storage (12 %) and reached 100 % in five days at room temperature. 1-MCP-treated pears showed flesh firmness values of 82 N after 90 days of cold storage and 18.7 N when they were removed from the cold storage and kept at 20 °C. The greatest acceptance index was attributed to 1- MCP pears after 90 days at 0 ± 1 °C followed by 5 days at 20 ± 1 °C (89.35). High acceptance indexes were attributed to MeJa (77.95) and control pears (76.40) after 30 days in cold storage followed by 5 days at room temperature. 1-MCP (0.3 µL L-1 , 24 hours at 0 ± 1 °C) treatment delays ripening and mitigates the internal browning in early harvested ?Bartlett? pears, that can be stored for up to 90 days at 0 ± 1 °C.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

2010

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Pears have been grown in the south region of Brazil, where the climatic conditions are favourable. The aim of this work was to determine the harvest maturity index as well as maximum storage period of 'Packham's Triumph? and 'Rocha' pears to maintain quality attributes. The ?Packham?s Triumph? fruit were harvested from a commercial orchard at 7 days intervals and flesh firmness was used as a maturity index (MI1=76, MI2=67 and MI3=58 N). ?Rocha? pears were harvested twice and they were considered as MI1 and MI3 because of the firmness values. The fruit were stored at 1±1C and 90-95% RH for 15, 30, 45 and 60 days and evaluated at the end of each storage period and after five days at room temperature (24±1C), simulating a helflife period. Flesh firmness, water loss, peduncle dehydration, epidermis colour, soluble solids, titratable acidity were measured. ?Packham?s? pears harvested at MI1 and MI2 showed firmness loss after 30 days of cold storage, whereas fruit harvested at MI3 retained the initial values, resulting in firmer fruit after 60 days (P<0.001). Fruit harvested in MI3 had less firmness loss after 5 days at room temperature following 45 and 60 days of cold storage. ?Rocha? pears harvested in MI1 and MI3 showed firmness reduction during cold storage, which was intensified at room temperature. Maximum values of water loss approached 6%. Fruit peduncles of both cultivars dehydrated after 60 days of cold storage, but their colour remained green, independent of harvest maturity index. ?Packham?s Triumph? and ?Rocha? pears harvested at MI3 showed better quality attributes after 60 days of cold storage plus 5 days of shelf-life than fruit harvested at other maturity stages.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Herbivory is generally regarded as negatively impacting on host plant fitness. Frugivorous insects, which feed directly on plant reproductive tissues, are predicted to be particularly damaging to hosts. We tested this prediction with the fruit fly, Bactrocera tryoni, by recording the impact of larval feeding on two direct (seed number and germination) and two indirect (fruit decay rate and attraction/deterrence of vertebrate frugivores) measures of host plant fitness. Experiments were done in the laboratory, glasshouse and tropical rainforest. We found no negative impact of larval feeding on seed number or germination for three test plants: tomato, capsicum and eggplant. Further, larval feeding accelerated the initiation of decay and increased the final level of fruit decay in tomatoes, apples, pawpaw and pear, a result considered to be beneficial to the fruit. In rainforest studies, native rodents preferred infested apple and pears compared to uninfested control fruit; however, there were no differences observed between treatments for tomato and pawpaw. For our study fruits, these results demonstrate that fruit fly larval infestation has neutral or beneficial impacts on the host plant, an outcome which may be largely influenced by the physical properties of the host. These results may contribute to explaining why fruit flies have not evolved the same level of host specialization generally observed for other herbivore groups.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

I knew a woman who lived by herself in a white brick house near the light house at Watson’s Bay. As she grew older, and her memory played tricks, she started to collect odd things. At breakfast each morning, she pulled the stickers off fruits—apples and pears and mandarins—and stuck them to her shoes. When she finished a meal, she stacked the dirty dishes on the couch in her sun room. In spring, when her garden bloomed, she cut orchids from their stems and arranged them in bowls of water around the house. When she ran out of bowls, she used butter containers instead...

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Elaborated Intrusion theory (EI theory; Kavanagh, Andrade, & May, 2005) posits two main cognitive components in craving: associative processes that lead to intrusive thoughts about the craved substance or activity, and elaborative processes supporting mental imagery of the substance or activity. We used a novel visuospatial task to test the hypothesis that visual imagery plays a key role in craving. Experiment 1 showed that spending 10 min constructing shapes from modeling clay (plasticine) reduced participants' craving for chocolate compared with spending 10 min 'letting your mind wander'. Increasing the load on verbal working memory using a mental arithmetic task (counting backwards by threes) did not reduce craving further. Experiment 2 compared effects on craving of a simpler verbal task (counting by ones) and clay modeling. Clay modeling reduced overall craving strength and strength of craving imagery, and reduced the frequency of thoughts about chocolate. The results are consistent with EI theory, showing that craving is reduced by loading the visuospatial sketchpad of working memory but not by loading the phonological loop. Clay modeling might be a useful self-help tool to help manage craving for chocolate, snacks and other foods.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In coastal areas, extreme weather events, such as floods and cyclones, can have debilitating effects on the social and economic viability of marine-based industries. In March 2011, the Great Barrier Reef Marine Park Authority implemented an Extreme Weather Response Program, following a period of intense flooding and cyclonic activity between December 2010 and February 2011. In this paper, we discuss the results of a project within the Program, which aimed to: (1) assess the impacts of extreme weather events on regional tourism and commercial fishing industries; and (2) develop and road-test an impact assessment matrix to improve government and industry responses to extreme weather events. Results revealed that extreme weather events both directly and indirectly affected all five of the measured categories, i.e. ecological, personal, social, infrastructure and economic components. The severity of these impacts, combined with their location and the nature of their business, influenced how tourism operators and fishers assessed the impact of the events (low, medium, high or extreme). The impact assessment tool was revised following feedback obtained during stakeholder workshops and may prove useful for managers in responding to potential direct and indirect impacts of future extreme weather events on affected marine industries. © 2013 Planning Institute Australia.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background The control of plant anthocyanin accumulation is via transcriptional regulation of the genes encoding the biosynthetic enzymes. A key activator appears to be an R2R3 MYB transcription factor. In apple fruit, skin anthocyanin levels are controlled by a gene called MYBA or MYB1, while the gene determining fruit flesh and foliage anthocyanin has been termed MYB10. In order to further understand tissue-specific anthocyanin regulation we have isolated orthologous MYB genes from all the commercially important rosaceous species. Results We use gene specific primers to show that the three MYB activators of apple anthocyanin (MYB10/MYB1/MYBA) are likely alleles of each other. MYB transcription factors, with high sequence identity to the apple gene were isolated from across the rosaceous family (e.g. apples, pears, plums, cherries, peaches, raspberries, rose, strawberry). Key identifying amino acid residues were found in both the DNA-binding and C-terminal domains of these MYBs. The expression of these MYB10 genes correlates with fruit and flower anthocyanin levels. Their function was tested in tobacco and strawberry. In tobacco, these MYBs were shown to induce the anthocyanin pathway when co-expressed with bHLHs, while over-expression of strawberry and apple genes in the crop of origin elevates anthocyanins. Conclusions This family-wide study of rosaceous R2R3 MYBs provides insight into the evolution of this plant trait. It has implications for the development of new coloured fruit and flowers, as well as aiding the understanding of temporal-spatial colour change.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this paper, we look at the concept of reversibility, that is, negating opposites, counterbalances, and actions that can be reversed. Piaget identified reversibility as an indicator of the ability to reason at a concrete operational level. We investigate to what degree novice programmers manifest the ability to work with this concept of reversibility by providing them with a small piece of code and then asking them to write code that undoes the effect of that code. On testing entire cohorts of students in their first year of learning to program, we found an overwhelming majority of them could not cope with such a concept. We then conducted think aloud studies of novices where we observed them working on this task and analyzed their contrasting abilities to deal with it. The results of this study demonstrate the need for better understanding our students' reasoning abilities, and a teaching model aimed at that level of reality.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This project tested modified gillnets designed by commercial net fishers in the Queensland East Coast Inshore Finfish Fishery (ECIFF) to try and identify gears that would mitigate and/or improve interactions between fishing nets and Species of Conservation Interest (SOCI). The study also documents previously unrecognised initiatives by pro-active commercial net fishers that reflect a conservation-minded approach to their fishing practices, which is the opposite of what is perceived publicly. Between 2011 and 2014, scientists from James Cook University and the Queensland Department of Agriculture and Fisheries teamed with commercial fishers representing the Queensland Seafood Industry Association and the Moreton Bay Seafood Industry Association to conduct field trials of various modified net designs under normal fishery conditions. Trials were conducted in Moreton Bay (southern part of the fishery) and Bowling Green Bay (northern) and tested different net designs developed by fishers to improve the nature of interactions between net fishing gear and SOCI.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A review of future management arrangements for the Queensland East Coast Trawl fishery was undertaken in 2010 to develop a management plan for the next 10 years. A key question raised at the start of the review process was: what should the management plan achieve? As with fisheries management in most countries, multiple management objectives were implicit in policy statements, but were poorly specified in some areas (particularly social objectives) and strongly identified in others (e.g., an objective of sustainability). As a start to the management review process, an analysis of what objectives the management system should aim to achieve was undertaken. A review of natural resource management objectives employed internationally was used to develop a candidate list, and the objectives most relevant to the fishery were short-listed by a scientific advisory group. Additional objectives specific to Queensland fisheries management, but not identified in the international review, were also identified and incorporated into the objective set. The relative importance of the different objectives to different stakeholder groups was assessed using the Analytic Hierarchy Process. As with other studies, the relative importance of the different objectives varied both within and between the different stakeholder groups, although general trends in preferences were observed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

An ecological risk assessment of the East Coast Otter Trawl Fishery in the Great Barrier Reef Region was undertaken in 2010 and 2011. It assessed the risks posed by this fishery to achieving fishery-related and broader ecological objectives of both the Queensland and Australian governments, including risks to the values and integrity of the Great Barrier Reef World Heritage Area. The risks assessed included direct and indirect effects on the species caught in the fishery as well as on the structure and functioning of the ecosystem. This ecosystem-based approach included an assessment of the impacts on harvested species, by-catch, species of conservation concern, marine habitats, species assemblages and ecosystem processes. The assessment took into account current management arrangements and fishing practices at the time of the assessment. The main findings of the assessment were: Current risk levels from trawling activities are generally low. Some risks from trawling remain. Risks from trawling have reduced in the Great Barrier Reef Region. Trawl fishing effort is a key driver of ecological risk. Zoning has been important in reducing risks. Reducing identified unacceptable risks requires a range of management responses. The commercial fishing industry is supportive and being proactive. Further reductions in trawl by-catch, high compliance with rules and accurate information from ongoing risk monitoring are important. Trawl fishing is just one of the sources of risk to the Great Barrier Reef.