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Effect of biological amendments on soil microbial properties and performance of pome fruit treesVan Schoor, Louise 12 1900 (has links)
Thesis (PhD(Agric))--Stellenbosch University, 2009. / ENGLISH ABSTRACT: The global movement in agriculture is towards more environmentally friendly, sustainable production practices, since the role of soil microbial functions in ensuring crop production and soil fertility has become
more evident in agricultural systems. Furthermore, with the impeding phase-out of methyl bromide, apple replant disease (ARD) is becoming an increasingly important problem and biological management practises are needed. Since microbial activity is generally carbon-limited in agricultural soil, it is widely accepted that management practices providing a range of organic compounds on a regular basis will tend to maintain
an active and diverse microbial population. It was hypothesised that the application of various biological amendments can affect soil microbial numbers and function, thereby having a positive effect on fruit tree growth and yield. The effect of continued applications of organic material, various microbial inoculants and biostimulants on tree performance were evaluated in conventional management systems. Field trials were established in a conventional pear orchard, potential apple replant disease sites, as well as an optimally
managed, high density apple orchard under controlled fertigation. The use of compost, compost extracts, a Bacillus inoculant and humates were investigated intensively. Furthermore, to improve our understanding
of soil biological systems a combination of simple, practical methods were used to evaluate the effect of biological amendments on soil microbial properties and effects were related to tree performance. Regular application of compost extract in combination with compost showed the most significant effect in improving tree performance in commercial pome fruit orchards under various conditions. In the pear orchard, cumulative yield over the first two seasons was improved by more than 50% compared to controls,
while in the fertigated orchard yield was improved by 22%. Biological amendments also showed improved growth in orchards suffering from stunted growth symptoms typical of ARD. However, in severe ARD cases methyl bromide fumigation showed the most consistent effects. Other biological amendments which showed positive effects on yield were application of Bacillus inoculants (Biostart®) in combination with a
labile C source and a low dosage humate product, as well as a combination of compost and humates. It was clear that a combination of labile organic matter and a diverse group of microorganisms showed most promise. Although for some specific treatments increased microbial numbers and activity may have resulted in improved tree performance, in general, changes in culture-based plate counts, soil enzyme activity and carbon utilisation profiles could not be used as an indicator of yield. It was suggested that
improved synchronisation of nutrient release and plant uptake, as well as microbial phytohormone
production, may play an important role in improving tree performance with application of biological amendments. More research is needed on the exact mechanisms through which compost extracts improve yield and studies on root growth proliferation, as well as effects in the rhizosphere are recommended. / AFRIKAANSE OPSOMMING: Binne lanbouverband is daar tans wêreldwyd die neiging om die uitwerking van produksie-praktykte op die omgewing in ag te neem en sodoende meer verantwoordelik op te tree. Omdat die belangrike rol wat grondmikro-organisme funksionering in volhoubare verbouingspraktyke speel nou deeglik besef word, word meer volhoubare bestuurspraktyke bepleit. Hiermee saam, noodsaak aspekte soos die uitfasering van
metielbromied vir die beheer van appelhervestigingsiekte, dat biologiese bestuurspraktyke meer aandag geniet. Daar word geredelik aanvaar dat gereelde toediening en aanvulling van organiese materiaal ‘n aktiewe, diverse mikrobe populasie in die grond tot gevolg sal hê. Die hipotese is gestel dat die toediening
van ‘n verskeidenheid biologiese produkte grondmikrobe getalle en werking gunstig kan beïnvloed. Dit kan moontlik weer aanleiding gee tot positiewe reaskies wat die groei en drag van vrugtebome betref. In hierdie studie is die uitwerking van voortgesette toedienings van organiese materiaal, mikrobiese inokulante, asook
biostimulante, op die prestasievermoë van vrugtebome ondersoek. Veldproewe is uitgelê in ‘n
konvensionele peerboord, verskeie boorde met moontlike appelhervestigingsiekte probleme, asook ‘n hoëdigtheidsaanplanting appelboord onder optimale bestuur. ‘n Deeglike ondersoek is gedoen met betrekking tot die gebruik van kompos, komposekstrak, Bacillus-inokulante en humate. Eenvoudige, praktiese metodes is aangewend om vas te stel hoe biologiese toevoegings grondmikrobe eienskappe beïnvloed en of dit verband hou met veranderinge in boomprestasie. Die studie het aangetoon dat die gereelde toediening van komposekstrak saammet kompos, betekenisvolle
verbetering in boomprestasie van kernvrugboorde teweeg bring onder verskeie omstandighede. Die
kumulatiewe opbrengs van ‘n peerboord is oor twee seisoene met meer as 50% verhoog teenoor die
kontrole. In ‘n optimaal bestuurde appelboord onder sproeibemesting, is opbrengs met 22% verhoog in vergelyking met die kontrole. Biologiese toevoegings het ook groei verbeter in boorde waar appelhervestigingsiekte bome se groei vertraag het. In die geval van ernstige appelhervestigingsimptome het metielbromied egter steeds die mees konstante positiewe uitwerking gehad. Ander biologiese toevoegings wat ‘n gunstige uitwerking op opbrengs getoon het, was ‘n kombinasie van Bacillus inokulante, ‘n lae dosis humaat en ‘n aktiewe koolstofbron, asook kompos in kombinasie met humate. Dit is duidelik dat ‘n kombinasie van ‘n maklik afbreekbare koolstofbron (soos kompos) tesame met ‘n diverse
groep mikroorganismes mees belowend is vir gebruik in biologiese verbouingssisteme. Resultate toon dat veranderings in aantal organismes gemeet deur plaattellings, die aktiwiteit van grondensieme, en verbruikspotensiaal van verskillende koolstofbronne, nie as ‘n aanduiding van boomprestasie gebruik kan word nie. Daar is voorgestel dat verbeterde sinkronisasie van voedingselementvrystelling en plantopname,
sowel as produksie van plantgroeihormone deur mikrobe, moontlik ‘n rol speel by boomreaksies op
biologiese toevoegings. Meer navorsing wat verband hou met die meganisme waardeur komposekstrak opbrengs verbeter, is nodig. Verder word studies op fynwortelontwikkeling sowel as aspekte van die wortelrisosfeer aanbeveel.
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Woolly apple aphid : interactions within an orchad systemFitzgibbon, Frances, 1954- January 1996 (has links) (PDF)
Errata and addenda attached. Bibliography: leaves 195-211. This thesis is concerned with the biology of Eriosoma lanigerum (WAA) and its parasitoid (Aphelinus mali), the impact of the pest on the crop and the effects of pesticides used routinely in South Australian orchards on both woolly apple aphid and the parasitic wasp. The study identifies current management practices of apple growers in South Australia. Aspects of the biology of WAA and A.mali are examined. Work is also done on the toxicity against WAA and A.mali of insecticides used in the control of codling moth and phytophagous mites. The effects of WAA infestation on the growth of young trees are investigated. The seasonal activity of WAA on mature trees is determined over a two season period.
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Woolly apple aphid : interactions within an orchad system / by Frances Fitzgibbon.Fitzgibbon, Frances, 1954- January 1996 (has links)
Errata and addenda attached. / Bibliography: leaves 195-211. / xviii, 211 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis is concerned with the biology of Eriosoma lanigerum (WAA) and its parasitoid (Aphelinus mali), the impact of the pest on the crop and the effects of pesticides used routinely in South Australian orchards on both woolly apple aphid and the parasitic wasp. The study identifies current management practices of apple growers in South Australia. Aspects of the biology of WAA and A.mali are examined. Work is also done on the toxicity against WAA and A.mali of insecticides used in the control of codling moth and phytophagous mites. The effects of WAA infestation on the growth of young trees are investigated. The seasonal activity of WAA on mature trees is determined over a two season period. / Thesis (Ph.D.)--University of Adelaide, Dept. of Crop Protection, 1997
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Apple scab (Venturia inaequalis) and pests in organic orchards /Sandskär, Boel, January 2003 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 5 uppsatser.
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Grönsöö park och trädgård 1820-1925 : tre familjemedlemmars odling, upplevelser och dokumentation i förhållande till dagens anläggning.Tandre, Anna, January 2008 (has links)
Diss. (vol. 1-2) Uppsala : Sveriges lantbruksuniversitet, 2008.
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The effect of different water and nutrient management strategies on the calcium content in apple fruitJoubert, Jorika 03 1900 (has links)
Thesis (MscAgric (Horticulture))--University of Stellenbosch, 2007. / Production of quality fruit is the main aim in horticultural crops. Numerous research reports
stress the important role of calcium (Ca) in maintaining firmness and preventing the
development of physiological disorders in fruit. This study focused on the effect of water and
nutrient management strategies, rootstocks and foliar Ca applications on fruit Ca content.
Final Ca content/concentration in apple fruit at harvest did not differ significantly between
treatments water with micro jets (hand nutrition), water and nutrients with fertigation, or
water and nutrients with pulsating drip when applied to ‘Brookfield Gala’ trees in third leaf,
on two rootstocks (M793 and M7).
In the second trial, three Ca levels were applied to ‘Brookfield Gala’ trees through a pulsating
drip system during three phenological periods to evaluate the effect on Ca uptake of the fruit.
During the second season, application of high Ca levels for the period full bloom to harvest
gave a higher fruit Ca concentration than with applications of standard or low Ca.
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Stikstofomsettinge in gronde met spesiale verwysing na lupine as bron van stikstof vir boorde en wingerdeFourie, S. 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 1955. / ENGLISH ABSTRACT: no abstract available / AFRIKAANSE OPSOMMING: geen opsomming
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Revitalizace krajiny v ptačí oblasti a evropsky významné lokalitě Doupovské Hory / Revitalization of landscape in Special protection areas and Sites of Community Importance Doupovské MountainsCIBULKOVÁ, Renata January 2014 (has links)
This thesis is concerned with keeping the gene pool of traditional fruit varieties and keeping the locality character for the extensive fruit orchard. Here is treated in detail the characterization of the area of the concerned place, selection of suitable varieties and their Pomology. Together with an evaluation of suitable places for the final planting are also calculated costs for the outplanting.
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Microbial community structure as an indicator of soil health in apple orchardsCaleb, Oluwafemi James 03 1900 (has links)
Thesis (MSc (Microbiology))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The relationship between various land management practices, soil properties and the soil
microbial communities are complex and little is known about the effect of these interactions
on plant productivity in agricultural systems. Although it would be advantageous to have a
single organism or property that can be used as a measure of soil health, it may not be
possible. Soil organisms which include both the microorganisms as well as soil fauna are
subjected to the effect of their immediate environment. This microenvironment in turn is
determined by the soil properties as well as above ground flora and their interactions. Most
soil indicators interact with each other, and these interactions can modify or influence the soil
properties. The complexities of the interactions between critical soil indicator values often
preclude its practical use by land managers and policy makers. However, soil microbial
communities (e.g. diversity and structural stability) may serve as a relative indicator of soil
quality. These communities are sensitive to land management practices and changes in the
microenvironment.
The objective of this study was to gain an understanding of the complex relationships by
investigating the effect of conventional, integrated and organic apple production systems on
the physical, chemical and biological (particularly soil microbial diversity) properties of the
soil. Automated Ribosomal Intergenic spacer analysis (ARISA) was used to characterise
fungal (F-ARISA) and bacterial (B-ARISA) communities from soil samples obtained from an
experimental apple orchard in Elgin, Grabouw. The intergenic spacer (ITS) region from the
fungal rRNA operon was amplified using ITS4 and fluorescently FAM (6-
carboxylfluorescein) labelled ITS5 primers. Similarly, the 16S-23S intergenic spacer region
from the bacterial rRNA operon was amplified using ITSR and FAM-labelled ITSF primers.
The sensitivity of the technique allowed us to discriminate between the soil microbial
communities of the different treatments. From our results we observed significant increase (p
< 0.05) in the fungal community diversity between the February and April samples, while the
bacterial community diversity was consistent (p > 0.05). Also, treatments with mulch showed
a significantly higher microbial diversity than the other treatments at a 5 % significance level.
Fungal communities showed significant correlation with the potassium concentration in the
soil, while bacterial communities depicted a significant correlation with the soil phosphorous
concentration. Based on the results we concluded that different management practices have a significant
effect on the soil microbial communities and that these communities are particularly sensitive
to small changes in the environment. However, there is still a need to determine what the
composition of the soil microbial communities are to be able to correlate our observations
with soil health. / AFRIKAANSE OPSOMMING: Die verhouding tussen verskillende landboubestuurspraktyke, grondeienskappe en die
mikrobiese gemeenskappe in grond is kompleks en weinig is bekend oor die uitwerking van
hierdie interaksies op die produktiwiteit van landboustelsels. Alhoewel dit voordelig sou
wees om ‘n enkele organisme of eienskap te kan hê wat die gesondheid van grond kan meet,
sal dit dalk nie moontlik wees nie. Grondorganismes wat die mikroörganismes sowel as die
grondfauna insluit, is onderworpe aan die invloed van hulle onmiddelike omgewings.
Hierdie mikro-omgewings op hulle beurt word weer beïnvloed deur die grondeienskappe
sowel as die die oppervlak flora en hulle wisselwerkinge. Meeste van die grondaanwysers
toon ook wisselwerkinge met mekaar, en hierdie wisselwerkinge kan die grondeienskappe
beïnvloed or selfs verander. Die kompleksiteit van die wisselwerkinge tussen kritiese grond
aanwysers is meestal die rede waarom dit nie deur grondbestuurders en beleidsmakers
gebruik word nie. Dit is ongeag die feit dat grond mikrobiese gemeenskappe (bv. diversiteit
en stukturele stabiliteit) mag dien as ‘n relatiewe aanwyser van grondkwaliteit. Hierdie
gemeenskappe is sensitief vir bestuurspraktyke en veranderinge in die mikro-omgewing.
Die doel van die studie was om die ingewikkelde verhoudings in die grondgemeenskappe te
bestudeer en die uitwerking van konventionele, geïntegreerde en organiese appel produksie
sisteme op die fisiese, chemiese en biologiese eienskappe (veral die grond mikrobiologiese
diversiteit) te bepaal. Geoutomatiseerde Ribosomale Intergeniese Spasie Analise (ARISA) is
gebruik om die fungus (F-ARISA) en bakteriese (B-ARISA) gemeenskappe van
grondmonsters wat vanaf ‘n proef appelboord in Elgin (Grabouw) verkry is, te bepaal. Die
intergeenspasie (ITS) area van die fungus rDNA operon is vermeerder deur die ITS4 en
fluoresserende FAM (6-karboxylfluorescein) gemerkte ITS5 inleiers te gebruik. Soortgelyk is
die 16S-23S intergeenspasie area van die bakteriese rDNA operon vermeerder deur ITSR en
FAM-gemerkte ITSF inleiers te gebruik.
Die sensitiwiteit van die tegniek laat ons toe om te onderskei tussen die grond mikrobiese
gemeenskappe vanaf verskillende grondbehandelings. Vanuit die resultate kon ons aflei dat
daar ‘n toename (p < 0.05) in die fungus gemeenskap diversiteit vanaf Februarie to April was
terwyl die bakteriese gemeenskap ‘n konstante diversteit getoon het (p > 0.05). Behandelings
met grondbedekking het ook ‘n beduidend hoër mikrobiese diversiteit getoon as ander
behandelings. Fungus gemeenskappe het beduidende korrelasies getoon met kalium konsentrasies in die grond, terwyl bakteriese gemeenskappe ‘n beduidende korrelasie getoon
het met grond fosfor konsentrasies.
Gebaseer op die resultate kon ons aflei dat verskillende bestuurspraktyke ‘n uitwerking kan
hê op die grond mikrobiese gemeenskappe en dat hierdie gemeenskappe sensitief is vir klein
veranderinge in die omgewing. Dit sal egter nog nodig wees om die spesifieke samestelling
van die grond mikrobiese gemeenskappe te bepaal voor ons hierdie waarnemings kan
korreleer met grondgesondheid.
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Medições do saldo de radiação em copas de cafeeiros e limeiras ácidas por sistemas de integração espaço-temporal e estimativas por técnicas de modelagem / Measurements of net radiation of the canopy of coffee and acid lime trees in hedgerows by spatiotemporal integration systems and estimates by modelling techniquesSimon, Jones 16 June 2010 (has links)
A energia radiante absorvida pelas copas tem aplicação em estudos de fotossíntese e transpiração de plantas arbóreas. Sua determinação não é simples. Nas últimas duas décadas tem sido realizados trabalhos sobre interceptação de radiação por espécies arbóreas isoladas ou em renques, envolvendo tanto radiação de ondas curtas como de ondas longas (saldo de radiação, Rn). Uma técnica de medida de Rn utiliza radiômetros movendo-se em torno da copa de uma árvore (geometria esférica de medida) ou ao longo de copas de um renque (geometria cilíndrica). Uma alternativa é o uso de modelagem físico-matemática para estimativa de Rn, que também exige medidas para testar modelos. Considerando os poucos trabalhos nessa linha de pesquisa, o presente estudo objetivou: a) avaliar o desempenho de sistemas móveis de integração espaçotemporal de medidas de Rn em renque de um cafezal e de um pomar de limeira ácida localizados no Campus Luiz de Queiroz, USP, Piracicaba, SP; b) estabelecer relações do saldo de radiação das copas de cafeeiros (Rnc) e limeiras ácidas (Rnl) com o saldo de radiação de gramado (Rng) e irradiância solar global (Rg); c) avaliar o desempenho de três modelos físicomatemáticos de estimativa de Rn por comparação com as medidas realizadas com varredura da copa pelos saldo-radiômetros movimentando-se ao longo dos renques (geometria cilíndrica de medidas). Os estudos foram realizados nas quatro estações do ano e em três no pomar, iniciandose respectivamente no outono e no verão de 2008. Os sistemas integradores forneceram valores diários de magnitude coerentes com os de calor latente de vaporização da copa determinados por medidas de transpiração de uma árvore. O desempenho do sistema de grande porte utilizado no pomar exige testes adicionais. O curso diário de Rn em cada posição dos radiômetros em torno da copa mostraram padrões diferenciados conforme orientação do renque e época do ano. No cafezal foram encontradas muito boas relações de Rnc com Rg e Rng nas escalas de 15min, horária e diurna, exceto no verão para 15min e horária e no inverno, na escala diurna, para Rng. Para o pomar, as relações de Rnl com Rg e Rng foram boas nas três escalas temporais, exceto no verão para 15min e horária e no outono na escala diurna. Para o cafezal o modelo de Beer apresentou altos índices de confiabilidade nas épocas do ano, nas escalas horária e diurna; e no pomar se mostrou confiável para inverno, mas não no verão na escala diurna e na escala horária apresentou menor confiabilidade. O modelo de Pilau apresentou boa confiabilidade para o cafezal no outono e menor confiabilidade nas demais estações, enquanto na escala horária verificou-se boa confiabilidade no outono e inverno; para o pomar, o desempenho foi satisfatório para inverno nas duas escalas temporais e insatisfatório para verão na escala diurna. Para o cafezal o modelo de Oyarzun mostrou-se confiável na escala diurna, e menos confiável na escala horária no verão; para o pomar, apresentou boa confiabilidade em ambas escalas temporais no inverno e baixa confiabilidade no verão. / The amount of radiant energy absorbed by the canopy of trees has great application in photosynthesis and transpiration research. Studies of radiation interception by the canopies of an isolated or a sequence of trees in hedgerows have been carried out by a technique which employs moving radiometers around an isolated tree (spherical geometry of measurement) or along a part of a hedgerow (cylindrical geometry). This technique allows spatiotemporal integration of the values. Crop Modeling is an alternative approach to estimate the radiation balance of canopies (Rn). The present study had the following objectives: a) to evaluate the performance of systems for spatiotemporal integration of Rn measurements in hedgerows of a coffee and an acid lime crops at the Luiz de Queiroz Campus of the University of São Paulo, in Piracicaba, SP, Brazil; b) to establish relations of the net radiation of the coffee (Rnc) and of acid lime plants (Rnl) canopies with grass net radiation (Rng) and incoming solar radiation (Rg); c) to evaluate the performance of three models of Radiation Balance (Rn), by comparing modem results with measurements by the moving radiometers along the planting row (cylindrical geometry). The coffee experiment was carried out all year long starting in the fall of 2008 while for the orchard only three seasons were tested starting in the summer 2008. Measurements of Rn by the moving systems were considered reliable, but it is recommended further testing of that of the orchard. The daily course of Rn for each measurement around the canopy showed different patterns for the two crops, in agreement with planting row orientation and season. Concerning to relations of Rnc with Rg and Rng integrated for 15min, hourly and diurnal periods, they were very good for the coffee crop in the three timescales, excepting for the 15min and hourly timescales in the summer and for the Rng for the diurnal period in the winter. For the orchard, the relations of Rnl with Rg and Rng were good, excepting for the summer in the 15min and hourly and in autumn for the diurnal timescales. The Beer´s model showed good reliability for the coffee crop; while for the orchard it showed to be reliable in the winter, but not in the summer for the diurnal period; for the hourly periods it was less reliable. The Pilau´s model showed good reliability for the coffee crop for both the diurnal and hourly periods during the fall, but less reliability in the other seasons; for the orchard, its performance was reliable for the winter in the two timescales and not reliable for the summer in the diurnal scale. The Oyarzun´s model showed to be reliable in the diurnal timescale and less reliable in the hourly timescale for the summer; for the orchard, it showed good reliability for the winter and little reliability for the summer.
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