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A Pilot Study Assessing the User Benefit of Skin Photoprotectants Perceived by University of Arizona Pharmacy StudentsLaBuda, Jared, Wojcik, Paul January 2012 (has links)
Class of 2012 Abstract / Specific Aims: To perform a pilot survey assessing the user benefit perceived by University of Arizona students regarding topical photoprotectants and their ability to prevent solar skin damage, including sunburn and carcinogenesis. In addition, to analyze the data obtained from the survey to identify incongruence between the FDA defined indication for the OTC sun protectants and the anticipated benefit expressed by University of Arizona students.
Methods: An anonymous, paper based questionnaire consisting of four demographic questions and ten questions pertaining to sunscreen knowledge and use was distributed to students at the beginning of a full class. Questionnaires that were not at least ninety percent complete were excluded. All available students in the college of pharmacy in years one, two, and three were invited to participate.
Main Results: Based on the survey analysis, 75% of pharmacy students have insufficient knowledge of FDA-approved use and guidelines for this class of OTC drugs.
Conclusions: A need for training/instructional measures that aim at increasing adequate drug competency and consumer counseling skills has been identified in the area of FDA-regulated sunscreen products. An opportunity for an increased involvement of professional pharmacists in optimizing consumers' sunscreen selection and use has been identified.
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Effects of surround and shodow spray material on fruit sunburn and certain properties of Mango (Mangifera indica) treeMorudu, Tokela Marcus January 2003 (has links)
Thesis (M. A. Agricultural Management (Horticulture)) -- University of Limpopo, 2003 / Refer to document
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Ultraviolet-radiation induced skin inflammation: dissecting the role of bioactive lipidsPilkington, S.M., Rhodes, L.E., Nicolaou, Anna January 2011 (has links)
No / Acute exposure of human skin to the ultraviolet radiation (UVR) in sunlight results in the sunburn response. This is mediated in part by pro-inflammatory eicosanoids and other bioactive lipids, which are in turn produced via mechanisms including UVR-induction of oxidative stress, cell signalling and gene expression. Sunburn is a self-limiting inflammation offering a convenient and accessible system for the study of human cutaneous lipid metabolism. Recent lipidomic applications have revealed that a wider diversity of eicosanoids may be involved in the sunburn response than previously appreciated. This article reviews the effects of UVR on cutaneous lipids and examines the contribution of bioactive lipid mediators in the development of sunburn. Since human skin is an active site of polyunsaturated fatty acid (PUFA) metabolism, and these macronutrients can influence the production of eicosanoids/bioactive lipids, as well as modulate cell signalling, gene expression and oxidative stress, the application of PUFA as potential photoprotective agents is also considered.
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UVR exposure of NZ schoolchildrenWright, Caradee Yael, n/a January 2007 (has links)
Excess exposure to solar ultraviolet radiation (UVR) is the only readily modifiable skin cancer risk factor, and childhood exposure is implicated in melanoma aetiology. To assist the design and evaluation of child sun protection interventions in the school and community context, this first comprehensive study used electronic monitors to record time-stamped, second-by-second UVR exposure of 325 children (from 28 randomly selected New Zealand primary schools) who kept a diary record of concurrent activities and sun-protective practices and completed a sun-related knowledge, attitudes and usual behaviours questionnaire. School principals and Health promoters (HPs) were interviewed about school and community sun protection efforts.
Using the Haddon matrix and Ottawa Charter of Health Promotion to guide research, four potential domains of influence were identified: the physical and social environments, protective products, and host (child). Two key outcomes identified were child UVR exposure and sun-protective practices. A path model was developed where potential influences on these outcomes included school, community, host factors (demographics, skin type, sun-related attitudes, and sun-related knowledge), and pattern of concurrent outdoor activity. Seven specific hypotheses were defined to investigate the effects of host, school and community factors on UVR exposure, sun-protective practices, and sun-related knowledge, attitudes and behaviours.
To test for the effects of host factors, day of the week and activity on UVR exposure and sun-protective practices, linear mixed models containing these factors and interactions between Year level-sex, activity-Year level and activity-sex, accounting for clustering within schools and allowing for repeated measures, were applied. Logistic regression with a random school effect was used to assess differences in scored student questionnaire items. Structural equation modelling was implemented to consider associations between sun-related knowledge, attitudes and behaviours, and other explanatory factors for variations in UVR exposure and sun-protective practices.
Three of the seven specific hypotheses were supported. There were statistically significant differences in UVR exposure by sex, skin type, day of the week and activity, and sex-activity and Year level-activity interactions. Passive pursuits were associated with the highest UVR exposure rates compared to outdoor active, travel and unclassified pursuits.
There were statistically significant differences in sun-protective practices by sex, ethnicity and skin type, and sex-activity and Year level-activity interactions. Girls tended to have higher sun protection scores than boys, but were more likely to sunbathe and use sunscreen. Children identifying with Pacific Island ethnicities had higher scores than children with other ethnicities, and children with Fitzpatrick skin types I and II had higher scores than children with skin types III, IV and V.
School and community factors were not associated with UVR exposure, sun-protective practices, sun-related knowledge, attitudes and behaviours, but school and HPs� scores were relatively high, reflecting the significant time and effort spent promoting youth sun protection.
Trends for Year level indicated that whereas child sun-related knowledge increased with Year level, attitudes and behaviours supportive of sun protection declined. When considering sun-related knowledge, attitudes and behaviours simultaneously, knowledge was only significantly associated with behaviours when mediated by attitudes. The study findings have implications for child sun protection interventions.
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UVR exposure of NZ schoolchildrenWright, Caradee Yael, n/a January 2007 (has links)
Excess exposure to solar ultraviolet radiation (UVR) is the only readily modifiable skin cancer risk factor, and childhood exposure is implicated in melanoma aetiology. To assist the design and evaluation of child sun protection interventions in the school and community context, this first comprehensive study used electronic monitors to record time-stamped, second-by-second UVR exposure of 325 children (from 28 randomly selected New Zealand primary schools) who kept a diary record of concurrent activities and sun-protective practices and completed a sun-related knowledge, attitudes and usual behaviours questionnaire. School principals and Health promoters (HPs) were interviewed about school and community sun protection efforts.
Using the Haddon matrix and Ottawa Charter of Health Promotion to guide research, four potential domains of influence were identified: the physical and social environments, protective products, and host (child). Two key outcomes identified were child UVR exposure and sun-protective practices. A path model was developed where potential influences on these outcomes included school, community, host factors (demographics, skin type, sun-related attitudes, and sun-related knowledge), and pattern of concurrent outdoor activity. Seven specific hypotheses were defined to investigate the effects of host, school and community factors on UVR exposure, sun-protective practices, and sun-related knowledge, attitudes and behaviours.
To test for the effects of host factors, day of the week and activity on UVR exposure and sun-protective practices, linear mixed models containing these factors and interactions between Year level-sex, activity-Year level and activity-sex, accounting for clustering within schools and allowing for repeated measures, were applied. Logistic regression with a random school effect was used to assess differences in scored student questionnaire items. Structural equation modelling was implemented to consider associations between sun-related knowledge, attitudes and behaviours, and other explanatory factors for variations in UVR exposure and sun-protective practices.
Three of the seven specific hypotheses were supported. There were statistically significant differences in UVR exposure by sex, skin type, day of the week and activity, and sex-activity and Year level-activity interactions. Passive pursuits were associated with the highest UVR exposure rates compared to outdoor active, travel and unclassified pursuits.
There were statistically significant differences in sun-protective practices by sex, ethnicity and skin type, and sex-activity and Year level-activity interactions. Girls tended to have higher sun protection scores than boys, but were more likely to sunbathe and use sunscreen. Children identifying with Pacific Island ethnicities had higher scores than children with other ethnicities, and children with Fitzpatrick skin types I and II had higher scores than children with skin types III, IV and V.
School and community factors were not associated with UVR exposure, sun-protective practices, sun-related knowledge, attitudes and behaviours, but school and HPs� scores were relatively high, reflecting the significant time and effort spent promoting youth sun protection.
Trends for Year level indicated that whereas child sun-related knowledge increased with Year level, attitudes and behaviours supportive of sun protection declined. When considering sun-related knowledge, attitudes and behaviours simultaneously, knowledge was only significantly associated with behaviours when mediated by attitudes. The study findings have implications for child sun protection interventions.
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Studies towards understanding sunburn in applesMakeredza, Brian 12 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Research was carried out to increase the current knowledge on sunburn development and its
control in apples. In addition to its chief causes, viz. high irradiance and high temperatures, water
stress has long been thought to contribute to sunburn susceptibility. Certain fruit chemical and
textural characteristics have also been suspected to increase sunburn, while it is not clear how
factors such as crop load affect sunburn in relation to other fruit quality parameters. In red and
blushed cultivars, sunburn could be underestimated due to masking by the red colour overlay.
Half and total irrigation water were withheld for two weeks in ‘Cripps’ Pink’ apples while in a
concomitant trial, mulching with vermicompost (plus a thin layer of woodchips), woodchips,
plant compost and black geotextile were used to regulate plant water by reducing soil
evaporative loss. Sunburn increased with an increase in moisture stress. Mulching had no effect
on plant water status, but it generally enhanced plant photochemistry, reducing fruit surface
temperature (FST) and sunburn.
Chemical and textural characteristics of exposed, but non-burned ‘Cripps’ Pink’ apples were
compared with that of fruit with induced and naturally occurring sunburn. Flesh firmness, total
soluble solids (TSS), and titratable acidity (TA) of induced and naturally occurring sunburnt fruit
did not differ from each other, but were significantly different from the non-burnt fruit. Based on
this, we concluded that sunburn induces textural and compositional changes in sunburnt fruit
rather than some fruit being predisposed to develop sunburn due to their texture and chemical
composition. Differences in heat stress tolerance, flesh texture and chemical composition of sun
exposed and shaded fruit sides seem to relate to their light exposure history. The effect of crop load on sunburn and fruit quality were assessed on a fruit cluster level in
2008-09 and on a whole tree basis in 2009-10 in ‘Cripps’ Pink’. In 2008-09, sunburn, red colour
and the proportion of first grade fruit decreased with an increase in number of fruit per cluster.
Crop load did not have an effect on sunburn and fruit colour in 2009-10 although the lowest
thinning severity seemed to increase sunburn severity while the proportion of first grade fruit
was highest for the highest thinning severity. Fruit number per cluster had no effect on fruit size,
while at the whole tree level, fruit size decreased with increasing crop load. Flesh firmness,
starch breakdown, TA and TSS were neither affected by the number of fruit per cluster nor the
crop load of the tree as a whole.
Green ‘Granny Smith’ and ‘Golden Delicious’, blushed ‘Royal Gala’, ‘Fuji’, ‘Braeburn’ and
‘Cripps’ Pink’, and full red ‘Topred’ were used to assess how red colour (anthocyanins) masks
superficial sunburn browning and bleaching. The greater reduction in superficial sunburn, but not
in sunburn necrosis in red and blushed compared to green cultivars with increasing red colour a
month towards harvest seemed to confirm the effect of masking. / AFRIKAANSE OPSOMMING: Hierdie navorsing is verrig ter uitbreiding van die huidige kennis oor die ontwikkeling en beheer
van sonbrand in appels. Addisioneel tot die hoof oorsake van sonbrand, naamlik hoë irradiasie
en hoë temperatuur, word waterstres gesien as bydraend tot sonbrandsensitiwiteit. Daar word
ook vermoed dat sekere chemiese en teksturele eienskappe van die vrug sonbrand kan verhoog
terwyl daar nie duidelikheid is oor hoe faktore soos oeslading sonbrand relatief tot ander
vrugkwaliteitparameters kan affekteer nie. Die omvang van sonbrand in rooi en bloskultivars
kan dalk onderskat word vanweë maskering deur die oorliggende rooi pigmentasie.
Besproeiing is vir twee weke gehalveer of gestop in ‘Cripps’ Pink’ appels. Sonbrand het
toegeneem met ‘n toename in vogstres. ‘n Deklaag van vermikompos (plus ‘n dun laag
houtstukkies), houtstukkies, plantkompos en ‘n swart geotekstiel is toegedien om die plant
waterstatus te reguleer deur evaporasie vanuit die grond te beperk. Die deklae het geen effek op
die plant waterstatus gehad nie, maar het wel die blaar fotochemie bevorder en terselftertyd die
vrugoppervlaktemperatuur verlaag en sonbrand verminder.
Die chemiese en tekturele eienskappe van sonligblootgestelde ‘Cripps’ Pink’ appels sonder
sonbrand is vergelyk met vrugte met geïnduseerde sonbrand en vrugte met sonbrand wat
natuurlik ontwikkel het. Vrugvleisfermheid, totale oplosbare vastestowwe (TOV) en titreerbare
suur (TS) van vrugte met natuurlik en geïnduseerde sonbrand het nie onderling verskil nie, maar
het wel betekesnisvol verskil van vrugte sonder sonbrand. Ons het gevolglik afgelei dat
sonbrand teksturele en komposisionele veranderinge teweeg bring eerder as dat sekere vrugte gepredisponeer word om sonbrand te ontwikkel vanweë hul tekstuur en chemiese samestelling.
Dit kom voor dat verskille in hittestres toleransie, tekstuur en chemiese samestelling tussen die
sonligblootgestelde en skadu kante van appels verband hou met hul verskil in sonligblootstelling.
Die effek van oeslading op sonbrand en vrugkwaliteit in ‘Cripps’ Pink’ is ge-evalueer op
trosvlak in 2008-09 en op ‘n per boom basis in 2009-10. Sonbrand, rooi kleur en die proporsie
eersteklas vrugte het afgeneem met ‘n toename in die aantal vrugte per tros. Op ‘n per boom
basis is rooi kleur en sonbrand egter nie deur oeslading geaffekteer nie. Die laagste vlak van
vruguitdunning het wel oënskynlik die graad van sonbrand verhoog terwyl die hoogste vlak van
vruguitdunning tot ‘n toename in die proporsie eersteklas vrugte gelei het. Die aantal vrugte per
tros het geen effek op vruggrootte gehad nie terwyl vruggrootte afgeneem het met oeslading op
‘n heelboombasis. Vrugvleisfermheid, styselafbraak, TOV en TS is nie deur aantal vrugte per
tros of die oeslading per boom geaffekteer nie.
Groen ‘Granny Smith’ en ‘Golden Delicious’, rooiblos ‘Royal Gala’, ‘Fuji’, ‘Braeburn’ en
‘Cripps’ Pink’, en volrooi ‘Topred’ is gebruik om die maskering van oppervlakkige
sonbrandverbruining en –verbleiking deur rooi antosianien te bestudeer. Oppervlakkige
sonbrand het minder toegeneem in die maand voor oes in die rooi- en bloskultivars as in die
groen kultivars terwyl vrugkleur skynbaar nie die aanwesigheid van die meer sigbare
sonbrandnekrose geaffekteer het nie. Maskering speel dus ‘n rol in die aanwesigheid van sigbare
sonbrand.
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Fotoprotetores – otimização do processo de desenvolvimento, caracterização, estudo de estabilidade e avaliação em modelo animalBuzzo, Célia Maria Vargas da Costa 31 August 2016 (has links)
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Previous issue date: 2016-08-31 / Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq / The importance of using effective and safe sunscreens is an undeniable reality, requiring formulators to obtain enough technical and scientific knowledge to overcome trade barriers. For this purpose was conducted this study using factorial design in the optimization of processes in order to achieve a stable formulation of a sun protection factor (SPF) of medium protection, with action against dermal damage induced by UV radiation. To evaluate the influence of the independent variables (type of wax, emollient and sensory modifier) on the dependent variables (pH, droplet size, conductivity, spreadability, stickiness and FPS), it was elaborated a factorial design 2³ with 8 formulations, which were characterized in relation to the organoleptic and physico-chemical parameters. The results showed that the variables pH, conductivity and viscosity correlated by analysis of variance (ANOVA). Confronting all correlation factors - response, the formulations selected for stability study were F1, F2 and F5. The stability results revealed that F1 significant difference for viscosity (T90 - environment), F2 for viscosity (T60 - environment and refrigerator) and F5 to pH (T90 - environment and ultraviolet light). For registration purposes, it was continued the research on the safety testing required by Anvisa in F1 formulation due to have lower cost. 30 Swiss mice were used (Mus musculus), adult males housed under temperature controlled light / dark cycle of 12 / 12h with standard food and water ad libitum. Animals received UVB irradiation stemmed from a Philips® TL 40W lamp / 12 RS, divided into six groups (n = 5). After being sacrificed it was obtained histologic sections of skin stained with hematoxylin-eosin (HE) and measured the thickness of the skin layers and the number of nucleated cells for each animal. The histopathological results showed that the formulation chosen softened histopathologic skin changes with reduction of sunburn cells, the number of layers of nucleated cells in the epidermis and absence of inflammatory infiltrate in the subepidermal region, obtaining the expected protective effect. At the end the purpose of the study was achieved proving to be a very important work with scientific support, developed by factorial design, a not so used tool in cosmetology area. / A importância do uso de fotoprotetores eficazes e seguros é uma realidade indiscutível, sendo necessário que os formuladores detenham conhecimentos técnico e cientifico suficientes para ultrapassar as barreiras comerciais. Com esse propósito foi conduzido o presente estudo que utilizou o planejamento fatorial na otimização de processos a fim de obter uma formulação estável de fator de proteção solar (FPS) de média proteção, com ação contra danos dérmicos induzidos pela radiação UV. Para avaliar a influência das variáveis independentes (tipo de cera, emoliente e agente modificador de sensorial) sobre as variáveis dependentes (pH, tamanho de gotículas, condutividade, espalhabilidade, viscosidade e FPS), elaborou-se um planejamento fatorial 2³ com 8 formulações, as quais foram caracterizadas em relação aos parâmetros organolépticos e físico-químicos. Os resultados mostraram que as variáveis pH, condutividade e viscosidade apresentaram correlação por análise de variância (ANOVA). Ao confrontar todas as correlações fatores – resposta, as formulações selecionadas para o estudo de estabilidade foram F1, F2 e F5. Os resultados de estabilidade revelaram que F1 apresentou diferença significativa para viscosidade (T90 - ambiente), F2 para viscosidade (T60 - ambiente e geladeira) e F5 para pH (T90 - ambiente e luz ultravioleta). Para fins de registro, foi dada continuidade às pesquisas com os testes de segurança exigidos pela Anvisa na formulação F1 em virtude de possuir menor custo. Foram utilizados 30 camundongos Swiss (Mus musculus), machos adultos alojados sob temperatura controlada ciclo claro/escuro de 12/12h, com ração padrão e água ad libitum. Os animais receberam irradiação UVB provinda ® de uma lâmpada Philips TL 40W/12 RS, sendo divididos em seis grupos (n=5). Após serem sacrificados foram obtidos cortes histológicos da epiderme corados com hematoxilina-eosina (HE), sendo avaliada a espessura, o número de camadas de células nucleadas e o número de células de queimadura solar da epiderme, bem como a presença de infiltrado inflamatório na região subepidérmica de cada animal. Os resultados histopatológicos demonstraram que a formulação escolhida amenizou as alterações histopatológicas da pele, com redução do número de células de queimadura solar, do número de camadas de células nucleadas na epiderme e ausência de infiltrado inflamatório na região subepidérmica, obtendo o efeito protetor esperado. Ao final o objetivo do estudo foi atingido provando ser um trabalho de grande relevância e respaldo científico, desenvolvido por planejamento fatorial, ferramenta pouco utilizada na área de cosmetologia.
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The sunburn response in human skin is characterized by sequential eicosanoid profiles that may mediate its early and late phases.Rhodes, L.E., Gledhill, Karl, Masoodi, Mojgan, Haylett, A.K., Brownrigg, M., Thody, Anthony J., Tobin, Desmond J., Nicolaou, Anna January 2009 (has links)
Yes / Sunburn is a commonly occurring acute inflammatory process, with dermal vasodilatation and leukocyte infiltration as central features. Ultraviolet (UV) B-induced hydrolysis of membrane phospholipids releases polyunsaturated fatty acids and their subsequent metabolism by cyclooxygenases (COX) and lipoxygenases (LOX) may produce potent eicosanoid mediators modulating different stages of the inflammation. Our objective was to identify candidate eicosanoids formed during the sunburn reaction in relation to its clinical and histological course. We exposed skin of healthy humans (n=32) to UVB and for 72h examined (i) expression of pro- and anti-inflammatory eicosanoids using LC/ESI-MS/MS and (ii) immunohistochemical expression of COX-2, 12-LOX, 15-LOX and leucocyte markers, while (iii) quantifying clinical erythema. We show that vasodilatory prostaglandins (PG)E2, PGF2¿ and PGE3 accompany the erythema in the first 24-48h, associated with increased COX-2 expression at 24h. Novel, potent leukocyte chemoattractants 11-, 12- and 8-monohydroxy-eicosatetraenoic acid (-HETE) are elevated from 4-72h, in association with peak dermal neutrophil influx at 24h, and increased dermal CD3+ lymphocytes and 12- and 15-LOX expression from 24-72h. Anti-inflammatory metabolite 15-HETE shows later expression, peaking at 72h. Sunburn is characterized by overlapping phases of increases in COX products followed by LOX products that may regulate subsequent events and ultimately its resolution. / The Wellcome Trust
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The eicosanoid response to high dose UVR exposure of individuals prone and resistant to sunburnNicolaou, Anna, Masoodi, Mojgan, Gledhill, Karl, Haylett, A.K., Thody, Anthony J., Tobin, Desmond J., Rhodes, L.E. January 2012 (has links)
No / High personal UVR doses can be gained during leisure activities, causing intense self-resolving inflammation (sunburn) of unprotected skin. UVR activates release of membrane fatty acids and upregulates their metabolism by cyclooxygenases (COX) and lipoxygenases (LOX) to different eicosanoids. While COX-derived prostaglandin (PG)E2 is a potent mediator of sunburn vasodilatation, LOX-derived 15-hydroxyeicosatetraenoic acid (HETE) and its lipoxin metabolites may contribute to sunburn limitation. We explored the relationships between expression of these lipid mediators and the clinical and histological outcomes, comparing responses of individuals prone and more resistant to sunburn. An acute UVR exposure of 12 SED (standard erythema dose) was applied to buttock skin of 32 white Caucasians (n = 16 phototype I/II, n = 16 phototype III/IV), and over the subsequent 72 h assessments were made of skin erythema, immunohistochemical expression of leukocyte markers, COX-2, 12-LOX, 15-LOX and nitric oxide synthase (NOS), and eicosanoid levels by LC/ESI-MS/MS. Evidence of a significant inflammatory response was seen earlier in phototype I/II with regard to expression of erythema (4h, p < 0.001), neutrophil infiltration (24 h, p = 0.01), epidermal COX-2 (24 h, p < 0.05) and 12-LOX (24 h, p < 0.01), and dermal eNOS (24 h, p < 0.05) proteins, although CD3+ lymphocyte infiltration showed an earlier increase in phototype III/IV (24 h, p < 0.05). Although erythema was equivalent at 72 h in both groups, phototype I/II showed higher PGE2 accompanied by elevated 15-HETE, and a strong positive correlation was seen between these mediators (n = 18, r = 0.805, p = 0.0001). Hence anti-inflammatory eicosanoid 15-HETE may temper the pro-inflammatory milieu in sunburn, having greater influence in those prone to sunburn than those more resistant, given the same high UVR exposure conditions. / The Wellcome Trust
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Evaporative cooling of apple and pear orchardsVan den Dool, Kari 12 1900 (has links)
Thesis (MSc (Horticulture))--University of Stellenbosch, 2006. / A growing number of fruit producers in warm areas are adopting the use of overtree evaporative cooling (EC) as a technique to reduce sunburn and enhance colour development of red or blushed fruit. Because fruit do not have efficient mechanisms of utilising and/or dissipating solar radiation, fruit surface temperature may rise 10 – 15oC higher than the ambient air temperature, making them very susceptible to sunburn. Sunburn negatively affects the appearance of the fruit, and they cannot be sold for fresh market consumption, which receives the highest prices. Evaporative cooling uses a sprinkler system to cool the trees from above. Energy needed to evaporate the water is extracted from the fruit skin, cooling the fruit down. The air around the trees is cooled, and a more favorable microclimate is created in the orchard. Producers have also found that the use of EC just prior to sundown and sometimes around sunrise has improved colour development on red apples (especially early varieties) before harvest.
In this study, two apple (‘Cripps’ Pink’ and ‘Royal Gala’) and two pear (‘Rosemarie’ and ‘Forelle’) cultivars under EC were compared with control fruit in terms of maturity, colour, sunburn and concentrations of polyphenolics in the skin. Two EC treatments were given; early application starting from the second week in December, and late application starting two to four weeks before harvest. Photosynthetic responses were measured, as well as fruit and leaf temperatures. Underlying physiological responses of trees and fruit to EC were investigated, particularly the phenomenon of acclimation and the potential for colour development and heat stress. Fruit surface temperature of fruit under EC was found to be significantly lower than control fruit. In both apple cultivars a significant increase in fruit skin anthocyanin concentration and a decrease in phenolic content was found as the season progressed. In both pear cultivars there was a significant decrease in both anthocyanin and phenolic. No significant differences were found in anthocyanin content between treatments in either the apple or pear cultivars. In both apple cultivars a higher phenolic content was found in the peel of the EC treatments. A decrease of up to four percent in leaf and fruit surface temperature was found under EC. No significant difference in trunk circumference was found in any of the cultivars. The late EC treatment in ‘Cripps’ Pink’ had a significantly faster rate of budbreak than the control and early EC treatments. Significantly higher transpiration was observed in leaves under EC. ‘Royal Gala’ fruit under EC had less sunburn than control fruit. Unfortunately the system broke down on a hot day, causing more sunburn on ‘Cripps’ Pink’ fruit under EC.
Heat tolerance of apple fruit grown under EC was evaluated in ‘Cripps’ Pink’ and ‘Royal Gala’ by determining the maximum quantum yield of chlorophyll fluorescence (Fv/Fm). Measurements were also made 12 hours after the heat treatments to determine recovery. ‘Cripps’ Pink’ fruit from both EC treatments, but particularly the early EC treatment, were less resistant to heat stress than control (non-EC) fruit at the “threshold” air temperature of 45°C. Apples were able to recover from heat treatments in the range of 32-38oC fruit surface temperature, and generally also recovered fully after 43-45°C fruit surface temperature when exposure did not exceed four hours. This knowledge could be helpful in the management of sunburn, for example when determining the threshold temperature for the activation of evaporative cooling treatments.
Knowledge about the various effects evaporative cooling and the subsequent lowering of ambient temperatures has on fruit trees and fruit could contribute greatly to producers’ ability to grow high quality fruit. EC can be used successfully for controlling sunburn and increasing fruit colour, but the system needs to be controlled very carefully and care should be taken that it does not fail on a hot day, as it did during this study.
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