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Organic apple production in Sweden : cultivation and cultivars /Jönsson, Åsa, January 2007 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniversitet, 2007. / Härtill 5 uppsatser.
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Host-parasite relationship of Xiphinema americanum Cobb, 1913, on apple, corn, and strawberryWhite, Lyle Vernon, January 1960 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1960. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Evaporative cooling of apple and pear orchards /Van den Dool, Kari. January 2006 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.
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Genetic diversity in fruit and berry crops estimated with molecular markers /Gustavsson, Larisa, January 2008 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniversit, 2008. / Härtill 5 uppsatser.
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Evaluating the seasonal changes in calcium concentration and distribution in apple fruit after application of different calcium fertilisation strategiesWilsdorf, Robert Ernst 12 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Localized calcium (Ca) deficiencies frequently develop independent from total Ca supply and total fruit Ca concentration. Bulk mineral analyses is therefore not completely suitable for determination of the susceptibility of fruit in developing Ca-linked fruit physiological disorders like bitter pit, as it supplies insufficient information regarding the spatial accumulation of Ca within the fruit. Additional Ca is applied either as soil or foliar applications, where soil applications are applied either after fruit set (pre-harvest) or in the period after harvest. The contribution of these different methods of Ca application to the total Ca concentration in "Braeburn" fruit was quantified over three consecutive growing seasons. Foliar applications have been proven to be successful in suppressing bitter pit development and improving the Ca status of the fruit. The effectiveness of different formulations of foliar Ca products in influencing these parameters was also determined. Furthermore, the distribution pattern of fruit Ca resulting from different application strategies was mapped using particle induced X-ray emission technology.
In the "Braeburn" trial, mineral analyses indicated no significant differences between treatments in terms of Ca concentration at 80 days after full bloom (dafb). However, when soil applications occurred with active root growth (visually monitored), treatments differed significantly 80 dafb. Weekly foliar Ca applications from 28 dafb resulted in higher fruit Ca concentrations 80 dafb than a pre-harvest soil Ca application (January, 2010). A possible explanation for the inefficiency of pre-harvest soil Ca is the disintegration of xylem vessels from 40 dafb (before root uptake) for sensitive cultivars such as Braeburn. Bitter pit initiation has been shown to occur in the earlier part of the season. This, together with a reduced Ca supply to the fruit early in the season due to xylem disintegration (for sensitive cultivars), indicates the importance of early season foliar Ca applications. PIXE analyses were used to establish the radial Ca distribution in apples. Ca was concentrated in the skin and core, with very low values in the outer cortex. PIXE results indicated fruit Ca concentrations to be the lowest in the pre-harvest soil application treatment. This was in agreement with mineral analyses results. Ca enriched areas resulting from effective Ca delivery via the vascular bundles, had a profound effect on fruit Ca concentrations in the immediate core and cortex. At harvest, this effect was much more subtle and emphasizes the importance of untimely xylem rupturing on eventual fruit Ca concentration. At 80 dafb, treatments where foliar Ca was applied showed higher Ca concentrations in the outer cortex (where symptoms of bitter pit typically occur).
Calflo™ fruit had significantly higher Ca concentrations in "Braeburn" compared to fruits from Foliar GS™ and GG™ treatments. Calflo™ and Calcimax™ had a higher active Ca percentage (12%) compared to Foliar GSTM and GGTM (10%). Adding the Lecithin™ (surfactant) to Calcimax™ is not recommended as it did not improve its uptake.
In "Golden Delicious", the commercial spray program of seven, weekly foliar applications (Calcinit™) resulted in fruit with significantly higher Ca concentrations compared to other treatments. / AFRIKAANSE OPSOMMING: Kalsium (Ca) tekorte ontstaan gewoonlik in gelokaliseerde areas in die appelvrug en ontwikkel dikwels ten spyte van voldoende totale vrug Ca. Minerale analises van heel vrugte verskaf dus nie genoeg inligting aangaande die verspreiding van Ca in die vrug wanneer die ontwikkelling van fisiologiese defekte soos bitterpit ter sprake is nie. Addisionele Ca word gewoonlik aangewend as blaar- of grondtoedienings, waar grondtoedienings tipies voor-oes (net na set) of in die na-oes periode, toegedien word. Die bydraes van die verskillende toedieningsmetodes tot die totale Ca konsentrasie van "Braeburn" appels is geëvalueer oor drie agtereenvolgende seisoene. Blaartoedienings van Ca word algemeen gebruik om die voorkoms van bitterpit te beheer en die Ca konsentrasie van die vrug te verhoog. Die effektiwiteit van `n reeks blaartoedienings-produkte om hierdie faktore te verbeter, is ook ondersoek. Die spesifieke verspreiding van die Ca in die vrug is gekarteer na gelang van elke toediening deur middel van PIXE-analises (Particle induced X-ray emission).
In die "Braeburn" proef was daar geen beduidende verskille in terme van vrug Ca konsentrasie op 80 dnvb (dae na volblom) nie. Daarteenoor, was daar wel beduidende verskille by 80 dnvb toe grond toedienings saam met aktiewe wortelgroei geskied het (visuele inspeksie). Weeklikse blaartoedienings vanaf 21 dnvb het gelei tot vrugte met betekenisvol hoër Ca konsentrasies as die behandeling waar grondtoedienings slegs voor-oes geskied het (Januarie 2010). `n Moontlike oorsaak vir die oneffektiwiteit van voor-oes grondtoedings is die vroeë disintigrasie van xileem vesels in die vrug (soms voor 40 dnvb en voor die aanvang van wortelopname) in sensitiewe kultivars soos "Braeburn". Hierdie vroeë inhibering van Ca voorsiening, tesame met die vroeë inisiasie van bitterpit, beklemtoon die belangrikheid van blaarbespuitings vroeg in die seisoen. Die PIXE-analises wat aangewend is om die radiale verspreiding van Ca in die vrug te bepaal het getoon dat Ca meestal in die skil en kern van die vrug gekonsentreer was, met baie lae konsentrasies in die buitenste korteks. Die laagste Ca konsentrasies is waargeneem in vrugte van die behandeling waar voor-oes Ca slegs as `n grondtoediening geskied het. Hierdie waarneming is in ooreenstemming met die mineraalanalise resultate. Ca verykte areas, afkomstig van die naby geleë vaatbundels (xileem vesels), het egter die grootste effek op vrug Ca konsentrasie gehad. Hierdie effek was nie so groot by oes nie en beklemtoon dus die belangrikheid van die funksionaliteit van die vaatbundels. Blaartoedienings kon die Ca konsentrasie in die buitenste korteks suksesvol verhoog - waar simptome van bitterpit tipies voorkom.
Die Calflo™ behandeling het beduidende hoër Ca konsentrasies gehad as die Foliar GS™ en GG™ behandelings. Die Calflo™ en Calcimax™ behandelings het `n hoër aktiewe Ca persentasie (12%) relatief tot die Foliar GS™ en GG™ (10%) behandelings bevat. Die byvoeging van Lecithin™ by Calcimax™ word nie aanbeveel nie, omdat dit geensins Ca opname vermeerder het nie.
In die "Golden Delicious" proef het die kommersiële behandeling (Sewe weeklikse spuite van Calcinit™) gelei tot vrugte met die hoogste Ca konsentrasie van al die behandelings.
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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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The effect of mulching on tree performance and fruit quality of 'cripps' pink' applesKotze, Willem Petrus 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Three field trials were conducted to investigate the effects of mulching on the chemical and
biological aspects of the soil as it is reflected by tree performance and fruit quality in ‘Cripps’
Pink’ orchards.
In the two trials at Lourensford Estate, where only the soil type differed between sandy silt
loam (sandy) and heavy silt loam (heavy), mulches where used as an additive to the soil
surface together with a standard, commercial, inorganic fertilization program. Four different
mulch types: compost, wood chips, vermi-compost and a geotextile fabric, were compared to
a bare surface control in a randomized complete block design.
At the heavy silt loam site (site 1), the wood chips treatment was the most effective in
regulating diurnal soil temperatures in the top 10 cm of soil (2009/10), whereas all mulches
regulated average diurnal soil temperature similarly and more effectively than the control at
the sandy silt loam site (site 2).
After two seasons of treatment at site 1, the vermi-compost treatment significantly increased
soil phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), manganese
(Mn), zink (Zn) and boron (B) significantly compared to the control. The wood chips
treatment increased Na, K and Ca and compost only increased soil K significantly compared
to the control. For site 2, only wood chips (Na and K) and vermi-compost (Na, K and Mg)
showed significant increases in soil nutrient elements compared to the control.
Yield efficiency was significantly increased by the wood chips (both seasons) and vermicompost
(only 2009/10) treatments compared to the control in site 1. In site 2, none of the
treatments differed significantly in yield efficiency compared to the control treatment. The number of roots and fine feeder roots were increased (not sign) by the wood chips and
geotextile treatments compared to the control. In site 1, all treatments improved the number
of roots compared to the control treatment, in contrast with site 2, where the number of roots
of the control, compost and vermi-compost treatments was more similar.
Fruit quality showed significant differences between the wood chips and vermi-compost
treatments compared to the geotextile and control treatments for malic acid, at site 1, at
harvest in 2009. This did not differ significantly from the compost treatment.
Leaf mineral analysis only showed significant differences at site 2, in 2010, with significantly
increased for the following minerals and treatments: Mn (compost and geotextile treatments
versus other treatments), Fe (control treatment compared to all treatments except compost),
Zn (compost compared to all other treatments) and B (control and compost versus vermicompost,
wood chips and geotextile).
Fruit mineral analyses showed no differences between treatments at harvest 2009 for either
site and 2010, for site 1. At site 2, the Ca percentage of fruit from the wood chips treatment
was significantly higher than that of all treatments, except the geotextile treatment.
Only in the 2010 analysis at site 2, the mycorrhizal colonization was significantly influenced,
where all the mulching treatments showed an increase compared to the control. However, the
same trend was observed at site 1. At site 1and 2, the compost, wood chips and vermi-compost treatments in general showed a
decreasing trend in percentage plant parasitic and increasing trend in percentage free living
nematodes from 2009 to 2010. In general, the geotextile and control treatments showed an
increasing trend in the percentage plant parasitic and decrease in percentage free living
nematodes. However, this was not the case at 0 – 15 cm soil depth for site 1. In the third trial, at Elgin Experimental Farm (Elgin), bare surface chemical control was
compared to mulching in the tree row (mulch) and mulching together with regular application
of compost tea (mulch + compost tea). All treatments were combined with different inter row
management practices to compose a total of eight different treatments. In the tree row, the
control treatment received standard rates of inorganic fertilizer, which was compared to the
mulched only treatment.
Both the percentage of soil carbon and cation exchange capacity was significantly increased
by all the mulch treatments compared to the control. Furthermore, all the mulches increased
various soil minerals significantly, however of which only P was significantly increased in
both the leaves and fruit. The rate of soil microbial activity and mycorrhizal root colonization
was significantly increased by mulching treatments, but resulted in a significantly lower yield
efficiency compared to the inorganic control treatment. This can be ascribed partly to the
microbial activity of the compost mulch during spring, although it was not quantified per se
and to the increase in tree vigour at the end of the trial. The slow rate of N mineralization was
reflected indirectly by the significantly lower fruit N for the mulched treatments and the
lower rate of microbial activity during spring at this site. With regards to the addition of the
compost tea, no significant contributions were evident in terms of tree performance, soil
minerals or microbial activity over a period of seven years, compared to the application of
mulch only. Compared to the trial at Lourensford Estate, with no significant differences in fruit mineral
composition between treatments after two years, fruit mineral analyses of the Elgin trial
showed significant differences between treatments after six (2009) and seven (2010) seasons
for P for some treatments. Only in 2010 more treatments showed significant differences for
N, Mn, Fe and Zn as well. Regarding fruit quality, in agreement with the results at Lourensford Estate, differences were
not persistent across all seasons for treatments. / AFRIKAANSE OPSOMMING: Veldproewe is geloods om die effek van verskillende deklae op grond chemiese en –
biologiese aspekte en die effek daarvan op boom prestasie en vrugkwaliteit in ‘Cripps’ Pink’
appelboorde te ondersoek.
In die eerste twee proewe te Lourensford Landgoed, waar slegs die grondtipe verskil het
tussen die sanderige slik leem (ligter) en swaarder slik leem (swaar) gronde, is deklae
toegedien saam met ‘n standard bemestingsprogram en mikro-besproeiingstelsel. Vier
deklaagtipes: kompos, houtspaanders, vermi-kompos en geotekstiel material, is vergelyk met
die onbedekte, skoon bewerkte, kontrole in ‘n total ewekansige blokontwerp.
By die swaar grondtipe (perseel 1), was die houtspaanderbehandling die effektiefste om die
daaglikse skommelings in grondtemperatuur te reguleer in die boonste 10 cm, teenoor die
sanderige perseel (2), waar al die deklae die daaglikse grondtemperatuur meer effektief as die
kontrole behandeling gereguleer het.
By perseel 1, het die vermi-behandeling ‘n betekenisvolle toename getoon teenoor die
kontrole behandeling in grond fosfaat (P), kalium (K), kalsium (Ca), magnesium (Mg),
natriuim (Na), mangaan (Mn), sink (Zn) en boor (B). Alhoewel dit nog nie tans
gekwantifiseer kan word nie, is ‘n gedeelte van die toename heel moontlik te wyte aan die samestelling van die deklaag. Die houtspaander- en komposbehandelings het ‘n
betekenisvolle verskil in toename tot gevolg gehad in grond K en Na in vergelyking met die
kontrole. In die geval kan die toename van die komposbehandeling aan die invloed van die
sampestelling van die deklaag toegeskryf word, maar nie in die geval van die
houtspaanderbehandeling nie. Die geotekstielbehandeling het, soos verwag, nie
betekenisvolle verskille ten opsigte van die kontrole getoon nie, aangesien die samestelling
van die geotekstielmateriaal nie voedingstowwe tot die grond kan toevoeg nie. By perseel 2,
het beide die houtspaander- en geotekstielbehandelings betekenisvolle toenames in grond
elemente (K, Mg) getoon teenoor die kontrole behandeling. Die ander elemente het nie
noemenswaardige verskille teenoor die kontrole getoon nie. Weer eens kan die toename in
die vermi-kompos toegeskryf word aan die samestelling van die deklaag, maar nie in geval
van die houtspaanders nie, wat ‘n moontlike rol van ander faktore soos temperatuur en
grondvog in die opname en beskikbaarheid van voedingselemente toon.
Op 30 cm diepte in perseel 1, het die vermi-kompos behandeling betekenisvolle hoër Na, K,
Mg en P getoon as die kontrole. Die houtspaanderbehandeling het betekenisvolle hoër Na, K
en Ca getoon as die kontrole. Geen een van die ander behandelings het enige betekenisvolle
veranderinge ten opsigte van voedingselemente getoon nie. Vir perseel 2 by die gronddiepte,
het die houtspaanderbehandeling betekenisvolle toenames in grond Na en K getoon teenoor
die kontrole. Geen van die ander behandelings het enige betekenisvolle veranderinge ten
opsigte van voedingselemente getoon nie. By hierdie dieper gronddieptes is ‘n soortgelyke
verandering in elemente waargeneem as by die vlakker gronddieptes vir perseel 1, in geval
van P en K. Mg en Na het volgehoue verandering vir die vermi-komposbehandeling in die dieper gronddieptes getoon vir die makro-elemente, maar nog nie in geval van mikroelemente
nie. In perseel 2 – het toenames in K en Mg in die vermi-komposbehandeling ook
voortgeduur en die veranderinge vir beide persele mag toegeskryf word aan die samestelling van die deklae per se. Dit blyk dat die veranderinge in die komposbehandeling nie so
konstant voorgekom het in die materiaal wat in die proewe toegedien is nie. Nietemin kan die
kompos- en vermi-komposbehandelings ook ander grond faktore beïnvloed en die bydra van
die minerale elemente afkomstig uit die samestelling van die deklaag moet eers bereken
word alvorens afleidings gemaak word.
By beide persele het die komposbehandeling die opbrengseffektiwiteit verminder in
vergelyking met die kontrole behandeling. Die opbrengseffektiwiteit is betekenisvol verhoog
in die houtspaanderbehandeling (beide seisoene) en vermi-komposbehandeling (net 2009/10)
in vergelyking met die kontrole in perseel 1. In perseel 2 het teen behandeling betekenisvol in
opbrengseffektiwiteit verskil ten opsigte van die kontrole nie.
Die aantal wortels en fyn, voedingswortels het ‘n dramatiese (nie-betekenisvolle) toename
getoon by die houtspaander- en geotekstielbehandelings. In perseel 1 het alle behandelings
die aantal wortels verhoog ten opsigte van die kontrole in kontras met perseel 2, waar die
aantal wortels in die kontrole, kompos- en vermi-komposbehandelings ongeveer dieselfde
was.
Stamwaterpotensiaal het onveranderd gebly ongeag van die behandeling, wat moontlik
beïnvloed is deur die hoë besproeiingskedulering siklus. Geen verskille tussen behandelings
of persele is gevind nie.
Alhoewel dit net in die tweede seisoen (2010) gemeet is, was daar geen betekenisvolle
verskille in gemiddelde loot groei van eenjaarlote tussen die behandelings of persele nie. Vrugkwaliteit het betekenisvolle verskille getoon in appelsuur (malic acid) in die
houtspaander- en vermi-komposbehandelings teenooor die geotekstie- en kontrole
behandelings in perseel 1, by oes 2009. Laasgenoemde het nie betekenisvol van die kontrol behandeling verskil nie. Hierdie verskille het nie na opberging voortgeduur nie. Geen
betekenisvolle verskille in vrugkwaliteit het voorgekom by perseel 2, tydens oes, of na
opberging nie. Gedurende oes 2010, asook na opberging, is geen verskille in vrugkwaliteite
van enige persele opgemerk nie.
Behandelingsverskille in blaar-analises is waargeneem tussen vermi-kompos- en die ander
behandelings, met uitsondering van die geotekstielbehandeling in Februarie 2009, perseel 1.
Geen ander betekenisvolle verskille vir enige element het voorgekom tussen behandelings in
perseel 2 nie. Gedurende 2010 is geen betekenisvolle verskille tussen behandelings ten
opsigte van blaar-analises gevind vir perseel 1 nie.
Betekenisvolle verskille in blaar- en vrugmineraal-analises was in perseel 2 teenwoordig as
volg: Mn (kompos- en geotekstielbehandelings teenoor al die ander behandelings), Fe
(kontrolebehandeling teenoor alle ander behandelings behalwe die komposbehandeling), Zn
(komposbehandeling teenoor al die ander behandelings) en B (kontrole en
komposbehandelings teenoor vermi-, houtspaander- en geotekstielbehandelings (gedurende
2010.
Die vrugmineraal-analises het geen verskille getoon tussen behandelings by oes 2009 vir
enige perseel, of 2010 vir perseel, 1 nie. By perseel 2 was die Ca persentasie in die vrug in
die houtspaanderbehandeling betekenisvol hoër as die van die ander behandelings,
uitgesonder die geotekstielbehandeling. By perseel 1, het al die behandelings die persentasie mycorrhiza-kolonisasie verhoog in
vergelyking met die kontrole, alhoewel dit nie betekenisvol was nie. By perseel 2 was daar
wel ‘n betekenisvolle toename in die persentasie mycorrhiza-kolonisasie by al die
deklaagbehandelings in vergelyking met skoonbewerking van die kontrole behandeling. Die persentasie plant-parasitiese nematodes was baie variëerend met gronddiepte by beide
persele. Die houtspaander- en vermi-komposbehandelings in perseel 1 het ‘n afwaartse
tendens getoon in die persentasie plant-parasitiese en toename in persentasie vry-lewende
nematode vanaf 2009 na 2010, in die 0-15 cm diepte. In teenstelling, het die geotekstiel- en
komposbehandeling ‘n toenemende tendens getoon in die persentasie plant-parasitiese en
klein afname in persentasie vrylewende nematodes vanaf 2009 tot 2010. Geen betekenisvolle
verskille in nematode getalle is waargeneem in gronddiepte 15 -30 cm grond in die perseel
nie.
In perseel 2 is geen betekenisvolle verskille in aantal nematodes gevind gedurende die twee
seisoene tussen behandelings of binne persele op 0-15 cm gronddiepte nie. Nietemin het die
houtspaander-, kompos- en vermi-komposbehandelings die persentasie plant-parasitiese
verlaag en die van die vry-lewende nematode verhoog vanaf 2009 tot 2010, in vergelyking
met die kontrole in die 15-30 cm gronddiepte. Slegs die houtspaanderbehandeling het
betekenisvolle verskille getoon teenoor die kontrole. Die geotekstiel- het dieselfde tendens as
die kontrole behandeling getoon, met ‘n toename in persentasie parasities- en afname in
persentasie vry-lewende nematode. Die kontrole en geotekstielbehandelings het nie
betekenisvol van mekaar verskil nie.
Die aantal erdwurms en meso-fauna was baie laag tydens die eerste twee jaar by beide die
persele en data is daarom nie statisties verwerk nie. By die derde proef, is ‘n skoonbewerkte oppervlak, wat chemiese beheer (kontrole) behels
het, vergelyk met deklaagbehandelings in die boomry (deklaag) en behandelings waar
kompostee saam met die deklaag toegedien was in die boomry (deklaag + kompostee). Al die
behandelings is gekombineer met verkillende tussenry behandelings wat ‘n totaal van agt
verskillende behandelings behels het. Hierdie verslag konsentreer slegs op die behandelings in die boomry, waar die kontrole behandelings wat ‘n standaard bememestings program
ontvang het, vergelyk word met die deklaag behandelings, wat geen alternatiewe bemesting
ontvang het nie en as organise alternatiewe beskou word in ‘n ‘Cripps’ Pink’ appelboord.
Klem in die verslag is gelê op die hoof effekte van die behandelings op vrugkwaliteit.
Beide die persentasie grondkoolstof en die katioonuitruilkapasiteit het ‘n betekenisvolle
toename getoon by al die deklaagbehandelings in vergelyking met die kontrole behandeling.
Terselfdetyd, het al die deklaagbehandelings ook verskeie grondminerale betekenisvol
verhoog, waarvan slegs P betekenisvol in beide die blare en vrugte verhoog is. Die tempo van
grondmikrobe aktiwiteit en micorrhiza-kolonisasie van die wortels is betekenisvol verhoog
deur die deklaagbehandelings, maar het gerealiseer in ‘n betekenisvolle laer
opbrengseffektiwiteit in vergelyking met die anorganiese, kontrole behandeling. Dit kan
onder andere toegeskryf word aan die mikrobe aktiwiteit van die komposdeklaag gedurende
die lente – alhoewel dit nie per se in die studie gekwantifiseer is nie, sook die toename in
vegetatiewe groeikrag aan die einde van die proeftydperk. Dit is wel indirek gereflekteer
deur die betekenisvolle, laer vrug N van die deklaagbehandelings en die laer tempo van
mikrobe aktiwiteit gedurende die lente by die deklaagbehandelings op die perseel. Wat die
toedienning van kompostee betref, het dit geen betekenisvolle bydra gelewer in terme van
gewasprestasie, grondminerale of microbe-aktiwiteit oor ‘n tydperk van sewe jaar in
vergelyking met die behandelings waar die deklaag geen kompostee ontvang het nie. In vergelyking met die proef by Lourensford Landgoed, met geen betekenisvolle verskille in
vrug mineral-analises tussen die behandelings oor ‘n tydperk van twee jaar nie, het die proef
te Elgin wel betekenisvolle verskille tussen behandelings na 6 (2009) en 7 (2010) jaar getoon
in geval van P, vir sekere behandelings (4,7,8 versus 1,2,6). Slegs in 2010 het meer
behandelings betekenisvolle verskille getoon vir N, Mn, Fe en Zn. Rakende vrugkwaliteit - in ooreenstemming met resultate van 2009 vir perseel 1 te
Lourensford Landgoed - het beide seisoene betekenisvolle verskille ten opsigte van appelsuur
getoon in Elgin. Die verskille het egter nie konstant in al die behandelings voorgekom nie.
Stysel afbraak, totaal oplosbare stowwe en fermheid het ook betekenisvolle verskille tussen
behandelings getoon in Elgin – maar dit was nie konsekwent oor behandelings of seisoene nie
en het ook nie voorgekom in die Lourensford Landgoed persele nie.
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Consumer reference (of red-fleshed apples) an quantification of quality related traits, particularly skin and flesh colour, in apple breeding familiesThovhogi, Fhatuwani 12 1900 (has links)
Thesis (MScAgric (Horticulture))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: In order to develop a novel pink- or red-fleshed apple for the fresh consumer market,the red-fleshed genotype, ‘KAZ 91’ (Malus niedzwetzkyana Dieck.), was crossed with
‘Meran’ (M. domestica Borkh) at the Agricultural Research Council (ARC) apple breeding programme in South Africa. The objective of this study was to evaluate and quantify colour variability in the flesh and peel of this progeny (Family 1), to assess quality traits (i.e., acidity and total soluble solids) and phenolic levels in fruit peel and flesh, and to investigate consumer preference for the taste and appearance of redfleshed
apples. All data, except for consumer preference, were also collected on two
white-fleshed M. domestica Borkh families, i.e., ‘Reinette Burchardt’ x ‘Treco Red
Gala’ (Family 2) and ‘Meran’ x ‘Treco Red Gala’ (Family 3). Fruit of Family 1 seedlings were on average darker red with greater blush coverage
and higher anthocyanin and phenolic levels compared to fruits of Family 2 and 3. The
proportion of bearing trees with red-fleshed fruits in Family 1 increased from 25% in
2007 to 35% in 2008. The intensity and distribution of red pigmentation in the flesh
varied considerably between seedlings and even between individual apples from the
same tree. A high intraclass correlation coefficient was found for red-flesh coverage
within Family 1, indicating a high level of genetic determination that can be used in
breeding. When only red-fleshed seedlings were considered, an intermediate
repeatability coefficient (0.54) for red-flesh coverage indicates that the extent of red
flesh coverage varies to some extent between seasons. The effect of environmental
factors on red flesh colour needs to be assessed and breeders need to take care to
select for genotypes with stable flesh colour intensity and coverage. Small intraclass
correlations were found between families for other traits. No correlation was found for
anthocyanin and total phenolics in both peel and flesh or between anthocyanin levels
in the peel and flesh of Family 1 fruit. This suggests that red-fleshed fruit will not
necessarily be high in antioxidants – since phenolics is by far the greatest contributor
to fruit antioxidant capacity. The lack of a correlation between peel and flesh
anthocyanin levels also suggest that fruit with dark red flesh will not necessarily have
a dark red skin colour. Family 1 fruit were more prone to flesh browning and were
more acidic compared to fruit of Families 2 and 3. With regard to consumer preference for flesh colour, 74% of South African
consumers preferred white flesh while 64% preferred an attractive “floral” pattern
created by the combination of a red cortex and white core. Consumers indicated a
much lower liking for other distribution patterns and lower intensities of red flesh
colour. Consumers preferred the taste of apples that were crisp, crunchy and high in
apple flavour irrespective of flesh colour. Red-fleshed fruit were generally acidic or
had poor texture, and some were also astringent. However, despite a general dislike in
acidic fruit, consumers showed a preference for acidic fruit if that fruit also had high
red-flesh coverage. / AFRIKAANSE OPSOMMING: Appeltelers van die Suid-Afrikaanse Landbounavorsingsraad (LNR) Infruitec-
Nietvoorbij poog om unieke appelkultivars met ‘n pienk of rooi vleiskleur te
ontwikkel. Vir hierdie doel het hulle die rooivleis genotipe, ‘KAZ 91’ (Malus
niedzwetzkyana Dieck), gekruis met ‘Meran’ (M. domestica Borkh). Hierdie studie is
uitgevoer ten einde kleurvariasie, interne kwaliteitseienskappe (i.e., suurheid en totale
oplosbare vastestowwe) en vlakke van fenole in die vleis en skil van bogenoemde
kruisingkombinasie se nageslag (Familie 1) te evalueer en te kwantifiseer asook om
verbruikersvoorkeure vir die smaak en voorkoms van rooivleis appels te bestudeer.
Buiten vir verbruikersvoorkeure, is alle data ook ingesamel vir twee witvleis M.
domestica families, naamlik ‘Reinette Burchardt’ x ‘Treco Red Gala’ (Familie 2) en
‘Meran’ x ‘Treco Red Gala’ (Familie 3).
Familie 1 saailinge se vrugte was gemiddeld donkerder rooi met ‘n groter rooi blos en
hoër antosianien- en fenoolvlakke in vergeleke met vrugte van Families 2 en 3. Van
die Familie 1 saailinge wat wel vrugte gedra het, het 25% en 35% in onderskeidelik
2007 en 2008 vrugte met rooi vleis gehad. Die intensiteit en verspreiding van rooi
pigmentasie in die vleis het aansienlik varieer tussen saailinge en selfs tussen
individuele appels van dieselfde boom. ‘n Hoë intraklas korrelasie koëffisiënt is
gevind vir die proporsie van die vleis met rooi pigmentasie in Familie 1 nageslag. Dit
dui op ‘n hoë vlak van genetiese determinasie en vinnige vordering met teling vir
hierdie eienskap. Indien net rooi-vleis saailinge egter oorweeg word, word ‘n
intermediêre herhaalbaarheid koëffisiënt (0.54) vir die proporsie van die vleis wat rooi
is verkry, wat dui op aansienlike variasie tussen seisoene in die omvang van rooi
pigmentasie. Die effek van omgewingsfaktore op rooi vleiskleur behoort dus
bestudeer te word en telers moet let daarop om te selekteer vir genotipes met stabiele
vleiskleur intensiteit en bedekking. Die intraklas korrelasies tussen families vir ander
vrugeienskappe was klein. Antosianienvlakke en totale fenole in die skil en vleis van
Familie 1 vrugte het nie gekorreleer nie. Dit dui daarop dat rooivleis appels nie
noodwendig ‘n hoër antioksidantkapasiteit het nie – fenole maak by verre die grootste
bydrae tot die antioksidantkapisiteit van vrugte. Antosianienvlakke in die skil en vleis
van Familie 1 vrugte het ook nie gekorreleer nie wat daarop dui dat vrugte met ‘n
donker rooi vleis nie noodwendig ook ‘n donker skilkleur sal hê nie. Familie 1 vrugte was gemiddeld suurder as vrugte van Families 2 en 3 en Familie 1 vrugte se vleis het
gemiddeld ook meer verbruining ondergaan.
Ten opsigte van verbruikersvoorkeur vir vleiskleur is gevind dat 74% van verbruikers
‘n wit vleiskleur verkies het terwyl 64% gehou het van die aantreklike “blom” patroon
gevorm deur ‘n rooi korteks en wit kern. Verbruikers het aansienlik minder gehou
van enige ander verspreiding van rooi pigment in die vleis of van ‘n laer intensiteit
rooi kleur. In terme van smaak is geurige appels met ‘n bros tekstuur verkies ongeag
hul vleiskleur. Rooivleisappels was oor die algemeen suur met ‘n swak tekstuur.
Sommige rooivleisappels was ook frank. Tog, ten spyte van ‘n algemene afkeur in
suur appels, het verbruikers ‘n voorkeur getoon vir vrugte met ‘n kombinasie van hoë
suur en ‘n hoë proporsie vleis met rooi pigmentasie.
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Effect of kaolin applications on pome fruitLe Grange, Monique 04 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Sunburn is a major problem in the apple industry worldwide. A kaolin product, M-97-
009 (100% kaolin), originally developed for insect control, was evaluated for its efficacy
in controlling sunburn on pome fruit. Trials were conducted over two seasons in two
different areas of the Western Cape, South Africa. During the first season, 'Royal Gala',
'Fuji' and 'Granny Smith' apples were evaluated in the Koue Bokkeveld. The kaolin was
mixed with water and applied to the trees by means of a hand-gun regularly throughout
the season. In addition to the effect on sunburn, effects on yield, colour development,
snout beetle damage and other defects were determined. Sunburn was reduced on all the
cultivars tested, although not significantly on 'Granny Smith'. Inconsistent effects on
yield parameters were observed. The applications significantly reduced red colour on
'Fuji', but this problem was rectified by an improved application technique the following
season.
During the second season, additional apple cultivars and 'Rosemarie' pears were included
in the trials. The apple trials were conducted in the Elgin area, and the 'Rosemarie' trial
in the Koue Bokkeveld. Surround™ (95% kaolin) was applied to the trees by means of a
commercial "blower". The effects on sunburn, yield, colour development and fruit
maturity were determined. In contrast to the previous season, sunburn was not reduced
on any of the cultivars examined. Yield parameters were not affected except in the case
of 'Royal Gala' where the number of fruit was increased, and 'Cripps' Pink' where the
number of fruit was reduced. Fruit colour was not affected in the apple cultivars, but
chroma of 'Rosemarie' pears was reduced, indicating a less intense colour. The kaolin
applications had a variable effect on fruit maturity. The effect of the foliar applications
on photosynthetic photon flux density (PPFD), photosynthetic rate, stomatal conductance
and transpiration rate was determined. In addition to these spot measurements,
photosynthetic light response curves were determined. Measurements were taken on both
the inner and outer canopies The applications significantly reduced photosynthetic rates
in the inner canopy and reduced the apparent quantum efficiency of leaves on the outer
canopy. No significant effect on PPFD was found. It appears that the white coating
reflects light and allows less light to penetrate the leaf, thus reducing photosynthesis. Surround™ treatments could not counteract the damaging effects of the high temperatures
experienced in the Western Cape during this season and was not effective as a control
measure for sunburn. This does not appear to be a commercially viable solution for the
sunburn problem and it would be worthwhile to investigate the use of alternative options,
such as evaporative cooling. / AFRIKAANSE OPSOMMING: Sonbrand is een van die grootste probleme wat wêreldwyd in die appelbedryf ondervind
word. 'n Nuwe produk, M-97-009 (100% kaolien), is oorspronklik ontwikkel vir
insekbeheer in geïntegreerde plaagbeheer, maar daar is beweer dat dit moontlik sonbrand
op kemvrugte kan verminder. Proewe is oor twee seisoene uitgevoer in die Koue
Bokkeveld en ook in die Grabouw-omgewing in die Wes-Kaap. Tydens die eerste
seisoen is die effek van M-97-009 op 'Royal Gala', 'Fuji' en 'Granny Smith' appels
beoordeel. Die kaolien is met water gemeng en deur die loop van die seisoen met 'n
handspuit op die bome gespuit. Die effek van die produk op sonbrand, oesgrootte,
vruggrootte, kleurontwikkeling, kalanderskade en ander defekte is bepaal. Sonbrand is
op alle kultivars verminder, alhoewel nie betekenisvolop 'Granny Smith' nie. Die effek
van kaolien op oesparameters was rue konsekwent nie.
kleurontwikkeling op 'Fuji' benadeel, heel moontlik
Die toedienings het
as gevolg van die
toedieningstegniek. Met verbeterde toedieningsmetodes die volgende seisoen, is kleurontwikkeling
van 'Fuji' nie benadeel nie.
Tydens die tweede seisoen is die effek van kaolien op nog appelkultivars en 'Rosemarie'
pere ge-evalueer. Die appelproewe is in Elgin uitgevoer, terwyl die 'Rosemarie'-proefin
die Koue Bokkeveld uitgelê is. Surround™ (95% kaolien) is met kommersiële
spuitpompe toegedien. Weereens is die effek van die produk op sonbrand, oesgrootte,
vruggrootte, kleurontwikkeling en vrugrypheid bepaal. Sonbrand is nie verminder nie.
Vruglading tydens oes is nie betekenisvol beïnvloed nie, behalwe in die geval van 'Royal
Gala' waar die vruglading verhoog is, en 'Cripps' Pink' waar daar minder vrugte op die
gespuite bome was. Die Surround™ toedienings het geen uitwerking op kleur van appels
gehad nie, maar het die chromawaarde van 'Rosemarie' pere verlaag, d.w.s die vrugkleur
was minder intens. Die kaolienspuite het 'n uiteenlopende effek op vrugrypheid
gehad. Fotosintetiese foton vloeddigtheid (FFV), fotosintesetempo,
huidmondjieweerstand en transpirasietempo is gemeet en ligreponskurwes van beide die
buitenste en binneste blaardak is bepaal. Die Surround™ toedienings het fotosintese van blare ill die binneste gedeelte van die blaardak verminder en die
kwantumdoeltreffendheid van blare op die buitenste deel van die blaardak verminder.
Geen betekenisvolle effek is op FFV gekry nie. Dit wil voorkom asof die wit laag
kaolien op die bome lig weerkaats en veroorsaak dat minder lig na die blaar deurdring.
Dit verminder dan die fotsintesetempo. Met die baie warm weer wat in die Wes-Kaap
gedurende die tweede seisoen ervaar is, kon die SUITound™behandelings nie sonbrand
verhoed nie. Dit wil voorkom asof Surround™ nie 'n baie doeltreffende oplossing in
kommersiële boorde sal wees nie. Alternatiewe oplossings, soos byvoorbeeld
evaporatiewe verkoeling, saloorweeg moet word.
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Certificação de maçãs e a perspectiva do consumidor santa-marienseSanguinet, Eduardo Rodrigues January 2016 (has links)
O trabalho objetiva apresentar as características da certificação de maçãs e analisar o comportamento do consumidor do município de Santa Maria, localizado na região central do Rio Grande do Sul, Brasil. A análise compreende a discussão dos aspectos relacionados à valoração da certificação e das características desse produto agroalimentar no momento da compra. Como procedimentos metodológicos, adotou-se a revisão bibliográfica para compreender os processos de certificação e regulamentação dos mercados agroalimentares e para discutir aspectos relacionados ao comportamento do consumidor. Além disso, usaram-se dados secundários para compreender a realidade produtiva da maçã no Brasil e no mundo. Para discutir a relação entre os consumidores e o mercado de maçãs, construiu-se um formulário com questões abertas e fechadas sobre o perfil do consumidor, os aspectos considerados no momento da compra e seu nível de conhecimento acerca da certificação. Os formulários foram aplicados para uma amostra significativa para o município de Santa Maria, em quatro espaços supermercadistas. Para as análises, adotaram-se procedimentos estatísticos e descritivos, como testes paramétricos, não paramétricos e a estimação de um modelo de regressão logística para avaliar como o público consumidor valora a certificação. Os resultados apontam que o público estudado é heterogêneo. Constatou-se que o consumidor não se detém por informações sobre segurança transmitidas e apresentadas nas frutas através dos selos de certificação. Poucos consumidores afirmaram saber o que, de fato, é a certificação. Uma parcela maior afirmou que, além de não saber o significado, não considera a certificação da fruta relevante no momento da compra, valorizando mais outros aspectos e fatores, tais como aparência, tamanho e o preço da fruta. Concluise que o nível de conhecimento acerca das informações sobre segurança, inspeção e controle e certificação tendem a não ser tão importantes no momento da compra. Por final, concluiu-se que se a produção de maçãs fosse totalmente destinada ao mercado santa-mariense, de acordo com a demanda representada pelos consumidores, o fato da oferta dessa fruta possuir algum selo de certificação seria pouco relevante. / This paper aims to present the characteristics of the certification apples and analyze consumer behavior in the municipality of Santa Maria, located in the central region of Rio Grande do Sul, Brazil. The analysis includes the discussion of issues related to the valuation of certification and characteristics of agro-food product at the purchase time. As methodological procedures in the study, we adopted the literature review to understand the processes of certification and regulation of agrifood markets and to discuss issues related to consumer behavior. In addition, they used secondary data to understand the reality of apple production in Brazil and worldwide. To discuss about the relationship between consumers and the market for apples, built up a form with closed questions about the consumer profile, the aspects considered at the time of purchase and their level of knowledge about certification. The forms were applied to a significant sample for the municipality of Santa Maria in four supermarket spaces. For analysis, were adopted descriptive and statistical procedures such as parametric tests, as nonparametric tests, and the estimation of a logistic regression model to assess how the consuming public values the certification. The results show that the studied public is heterogeneous. It was found that the consumer do not value safety information transmitted and presented in fruits through the certification seals. Some few consumers know what certification is. A larger portion said that in addition to not knowing the meaning, does not consider the certification something relevant at the time of purchase, giving more importance to other aspects and factors, such as appearance, size and fruit price. It is concluded that the level of knowledge about information security, inspection and control and certification tend to not be as important at the time of purchase. By the end, it is concluded if that the production of apples was fully intended to Santa Maria market, according to the demand represented by consumers, the fact that the supply of this fruit have a certification label would not be relevant.
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