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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The effects of organic and inorganic mulches on the yield and fruit quality of ‘Cripps’ Pink’ apple trees

Van der Merwe, Johannes Dawid Prins 12 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Limited research is available on the effect of mulches on established orchards. Most of the information available stems from research conducted in newly planted orchards or on annual crops such as green peppers and strawberries under greenhouse conditions. To increase the current knowledge on the effect of mulches in established orchards, two field trials were conducted on 14 year old „Cripps‟ Pink‟ orchards. The one trial concentrated on the influence of mulches on the root environment and the other trial on the effect of mulches on growth, yield and fruit quality. Both trials were conducted at Lourensford Estate near Somerset West, but the sites differed in soil texture between lighter soil (Tukulu) and heavier soil (Clovelly). Four different mulches were used viz. compost, wood chips, vermi-castings (topped with thin layer of woodchips) and a woven geotextile fabric. These four treatments were compared to an un-mulched control, managed according to industry norms. After reducing irrigation volume in the 2010/2011 season, with a further reduction in the 2011/2012 season, more significant differences were obtained in nutrient levels of fruit and leaves compared to the 2008/2009 and 2009/2010 seasons of the trial. Leaf and fruit nutrients showed significant differences in both sites, but the differences were more pronounced on the lighter soil. At the heavier soil site, the vermi-castings, woodchips and compost treatments increased fruit phosphorus (P) during 2010/2011 and the control treatment increased fruit boron (B) during 2011/2012. Only leaf magnesium (Mg) was increased by woodchips and vermi-castings in 2011/2012 at this site. In the lighter soil site, the control treatment had the highest fruit B levels in 2010/2011 while the vermi-castings and the woodchips treatments had the highest fruit P levels in 2011/2012. For the same site, vermi-casting and compost treatments improved leaf potassium (K) uptake in 2010/2011 and 2011/2012, whereas woodchips and geotextile significantly improved leaf copper (Cu) uptake in 2010/2011 compared to the control. To determine if applied nutrients were trapped in the organic mulches over time, leading to a deficiency in the soil and eventually the tree, a mineral analysis was conducted on the organic mulches at the end of each season. Results of the two seasons indicated that vermi-castings contained higher total nutrient levels than the other two organic mulches, but the difference in nutrient levels were shown not to be directly related to the fertilisers applied during each season. In the case of vermi-castings, nutrient quantities in the original material applied at the beginning of each season were higher than those of the other organic mulches. The higher nutrient levels in organic in comparison to inorganic mulches were however not reflected in the fruit and leaf mineral analysis of these treatments. The overall treatment effect in terms of changes in nutrient levels in the tree became less significant when trees were over irrigated. This became evident as the differences between mulching treatments increased as the irrigation was reduced during the season, indicating the masking effect of irrigation on mulching. Evaluating the effect of mulches on growth, yield and fruit quality showed significant differences only at the heavier soil site. The vermi-casting treatment had significantly higher yield efficiencies than the control for the 2010/2011 season. Compost had the lowest yield efficiency at both sites, also during the previous two seasons that formed part of an earlier study (Kotze 2012). In 2011/2012, the compost treatment also showed significantly higher shoot growth than the control. Compost therefore could increase vegetative growth in established orchards on a heavier soil after application for four seasons. Taking the cost of mulching into account, wood chips are the only treatment that can be recommended without compromising fruit quality. Wood chips will sustain or even improve yield efficiency in an established orchard on especially heavier soil. Future research should study the effect of different amounts of irrigation on the various mulches, as the effect of irrigation was not evaluated in this study. / AFRIKAANSE OPSOMMING: Beperkte navorsing is beskikbaar oor die effek van deklae op bestaande boorde. Die meeste bestaande inligting is gegrond op proewe wat uitgevoer is op nuut aangeplante boorde of op eenjarige gewasse, soos groenrissies en aarbeie, onder kweekhuis toestande. Om bestaande kennis aan te vul rakende die effek van deklae op vrugproduksie en -kwaliteit in bestaande boorde, is twee veldproewe geloots in 14-jaar-oue „Cripps‟ Pink‟ appelboorde. Die een proef het gekonsentreer op die invloed van deklae op die wortel omgewing en die ander proef, op die effek van deklae op groei, opbrengs en vrugkwaliteit. Beide proewe is uitgevoer op Lourensford Landgoed naby Somerset-Wes en twee verskillende grondtipes is hiervoor gebruik: „n ligte grond (Tukulu) en swaarder grond (Clovelly). Vier verskillende deklaagtipes is gebruik naamlik: kompos, houtspaanders, „vermi-castings‟ (bedek met „n dun lagie houtspaanders) en geweefde geotekstiel materiaal. Hierdie vier behandelings is vergelyk met „n onbedekte kontrole wat volgens industrie norm bestuur is. Nadat die besproeiingsvolume verminder is in 2010/2011 en daarna weer in 2011/2012, het meer betekenisvolle verskille tussen behandelings voorgekom in nutriënt-vlakke van vrugte en blare in vergelyking met die eerste twee jaar van die proef (2008/2009 en 2009/2010). Blaar en vrug nutrient-vlakke het betekenisvolle verskille in beide persele getoon, maar die verskille was meer duidelik in die ligte grondtip. In die swaarder grond perseel het die „vermi-castings‟, houtspaanders- en kompos behandelings die vrug fosfaatvlakke (P) betekenisvol verhoog in 2010/2011. In die kontrole behandeling was vrug boorvlakke (B) betekenisvol hoër as die ander behandelings in 2011/2012. In hierdie perseel is net magnesium-vlakke (Mg) in die blare betekenisvol verhoog deur die houtspaanders- en „vermi-castings‟ behandelings in 2011/2012. In die ligte grond perseel het die kontrole behandeling die hoogste vrug B-vlakke in 2010/2011 gehad en die „vermi-castings‟ en houtspaander-behandelings gesamentlik, die hoogste vrug P-vlakke in 2011/2012. Die „vermi-casting‟ en kompos behandelings het kalium-vlakke (K) opname in die blare in 2010/2011 en 2011/2012 verbeter, terwyl die houtspaanders- en geotekstiel behandelings die koper-vlakke (Cu) in die blare in 2010/2011 verbeter het. Om te bepaal of die toediening van voedingstowwe oor tyd kan lei tot die „vashou‟ daarvan in „n organiese deklaag en dan tekorte van sekere nutriënte in die grond en uiteindelik die boom kan veroorsaak, is „n mineral analise van die organiese deklae uitgevoer aan die einde van beide seisoene. Resultate van die twee seisoene het getoon dat „vermi-castings‟ hoër totale nutrient-vlakke gehad het as die ander organiese deklae, maar die nutrient-vlakke was nie direk verwant aan die toegediende voedingstowwe nie. In die geval van „vermi-castings‟, was nutrient-vlakke van die moedermateriaal, wat toegedien is aan die begin van die seisoen, hoër as die van die ander organiese deklae. Hierdie hoër nutrient-vlakke van die organiese teenoor anorganiese behandelings, is nie gereflekteer in hoër nutrient-vlakke in die vrug- en blaar mineraal analises van die bome nie. Behandelings effekte rakende veranderinge in nutrient-vlakke in die boom, nadat die besproeiing verminder is, het verander in vergelyking met die van die vorige twee seisoene en is „n aanduiding van die verbloemende invloed van besproeiing op die prestasie van deklae. Evaluasie van die effek van deklae op groei, opbrengs en vrugkwaliteit het net betekenisvolle verskille in die swaarder grond perseel getoon. Die „vermi-casting‟-behandeling het „n betekenisvolle hoër opbrengseffektiwiteit as die kontrole getoon in 2010/2011. Kompos het die laagste opbrengseffektiwiteit in beide persele gehad en het resultate van die vorige twee seisoene van Kotze (2012) bevestig. Die betekenisvolle hoër lootgroei van kompos as die ander behandelings het net in 2011/2012 voorgekom. Kompos kan dus groei verhoog in „n gevestigde boord, in „n swaarder grond, indien besproeiing optimaal is. In terme van kostes, word die gebruik van houtspaanders as deklaag voorgestel vir „n gevestigde boord met „n swaar slik leem grond, aangesien daar geen nadelige effek op vrugkwaliteit was met die behandeling nie en die opbrengseffektiwiteit van die bome gehandhaaf en selfs verbeter is. Toekomstige navorsing kan die effek van besproeiing op verskillende deklaag tipes bestudeer, aangesien die bestaande proef dit nie kon aanspreek nie.
2

A Study of the Influence of Petroleum Mulches on Several Herbicides With Selected Vegetable Crops

Mills, C. Linnis 01 May 1968 (has links)
The effects of petroleum mulches on plant response to herbicides were studied at the Farmington Field Station . The herbicides were applied to the soil preemergent and by incorporation at one-half, normal and double the recommended rates with asphalt overlay. The herbicides and crops used were : Atrazine and Ramrod on sweet corn, PEBC and Diphenamid on tomatoes and EPTC and Trifluralin on snap beans. Germination, overall crop rating, grass and broad leafed weed control and yields were measured. Data recorded from these trials showed that herbicides are as effective under the asphalt when compared to plots with herbicide but no asphalt. Considering all herbicides and conditions, overall crop growth and weed control were not increased or decreased by the asphalt mulch. Germination and yield were not affected by the interaction of herbicides with the asphalt overlay on the three crops.
3

Synthetic Mulching Experiment

Cannon, M. D., Frost, K. R., Patterson, Lloyd 02 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
4

Synthetic Mulch for Cotton Still of Interest

Larsen, W. E. 02 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
5

The effect of organic matter on greenhouse plants

Hartman, Elmer Louis January 1932 (has links)
No description available.
6

Effect of Herbicide-Organic Mulch Combinations on Weed Control and Herbicide Persistence

Somireddy, Upender Reddy 06 January 2012 (has links)
No description available.
7

Perennial clovers and ryegrasses as understorey crops in cereals /

Bergkvist, Göran, January 2003 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.
8

Organic production of strawberries : focus on practical applications /

Berglund, Rakel, January 2007 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniversitet, 2007. / Härtill 4 uppsatser.
9

Coloured plastic mulches improve the growth and yield of the ‘Micro-Tom’ tomato in high-density plantings / Coberturas plásticas coloridas melhoram o crescimento e o rendimento do tomate "Micro-Tom" em plantios de alta densidade

Manganelli, Carla Constanza 10 October 2017 (has links)
Submitted by CARLA CONSTANZA MANGANELLI (carlacm.89@gmail.com) on 2017-12-01T15:28:42Z No. of bitstreams: 1 DISSERTAÇÃO DEFINITIVA - online - Repositorio.pdf: 996196 bytes, checksum: 7399044c17373c4a4a6d22f0e53e9bbf (MD5) / Approved for entry into archive by LUCIA SILVA PARRA null (lucia@ia.unesp.br) on 2017-12-04T12:14:50Z (GMT) No. of bitstreams: 1 manganelli_cc_me_jabo.pdf: 941849 bytes, checksum: 9248a7466ffb33e1a145b960af79cd2d (MD5) / Made available in DSpace on 2017-12-04T12:14:50Z (GMT). No. of bitstreams: 1 manganelli_cc_me_jabo.pdf: 941849 bytes, checksum: 9248a7466ffb33e1a145b960af79cd2d (MD5) Previous issue date: 2017-10-10 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / As coberturas plásticas têm diferentes pr opriedades térmicas e de radiação, e podem afetar o rendimento e a qualidade do tomate. Neste estudo, compararam - se a influência das coberturas plásticas coloridas (vermelho, azul, e cinza/preto) e a densidade de plantio no crescimento do tomateiro, o rend imento e a qualidade dos frutos com o da cobertura preta convencional e o solo descoberto (controle) no desenvolvimento do tomateiro ‘Micro - Tom’. Além disso, determinou - se a acumulação de pigmentos, a temperatura do solo e a água total aplicada. Os resulta dos indicaram que o peso seco e a área foliar das plantas cultivadas com cobertura azul, vermelha e cinza/preta foram significativamente maiores do que o tratamento controle em parcelas de alta densidade. Em comparação com o tratamento controle, o rendimen to total, o peso do fruto e o peso total de frutos por planta foram consequentemente melhorados nas plantas crescidas com cobertura vermelha e cinza/preta em altas densidades. Contudo, o número de frutos não foi afetado. Além disso, o tamanho do fruto aume ntou com cobertura vermelha em parcelas de baixa densidade. Por outro lado, as temperaturas do solo registradas sob a cobertura vermelha foram as mais adequadas para o tomateiro nessas condições climáticas. Em conclusão, os tratamentos com cobertura colori da afetaram positivamente o crescimento e o rendimento do tomateiro em parcelas de alta densidade, e a cobertura vermelha em particular poderia ser usada para melhorar o rendimento e o tamanho dos frutos de tomate ‘Micro - Tom’, devido à otimização da temper atura e o ambiente de luz. / Plastic mulches have different thermal and radiation properties, and they can affect tomato fruit yield and quality. In this study, the influence of coloured plastic mulches (red, blue and gray on black) and planting density on tomato growth, fruit yield and quality was compared with that of conventional black mulch and uncovered soil (control) in developing ‘Micro Tom’ tomatoe s. In addition, the pigment accumulation, soil temperature and total applied water were determined. The results indicated that the dry weight and leaf area of plants grown over blue, red and gray/black mulches were significantly higher than the control tre atment in high - density plots. Compared to the control treatment, the total tomato yield, fruit weight and total fruit weight per plant were consequently improved in plants grown over red and gray/black mulches at high densities. However, the fruit number w as not affected. In addition, the fruit size increased over red plastic mulc h when planted at a low density . In addition, the soil temperatures registered under the red mulch were the most suitable for the tomatoes in these climatic conditions. In conclusi on, treatments employing coloured mulch positively affected the growth and yield of tomatoes in high - density plots, and red mulch in particular could be used to improve the yield and fruit size of Micro - Tom tomatoes because of the optimization of the therm al and light environment. / 134597/2015-0
10

Soil Nutrient Cycling and Water Use in Response to Orchard Floor Management in Stone-Fruit Orchards in the Intermountain West

Culumber, Catherine Mae 01 May 2016 (has links)
Fruit growers in Utah and other areas across the Intermountain West are faced with growing production challenges stemming from declining soil quality and water resources. Population growth presents challenges in terms of the cost and availability of land, but also presents opportunities in the form of new marketing options such as organic fruit. Few certified organic fruit orchards are operating in Utah currently, which is attributed to a lack of locally tested and adapted organic management practices. An organic peach orchard trial evaluated the effectiveness of different organic management approaches to enhance soil quality and conserve water without compromise to fruit tree growth and fertility. Two tree-row treatments: ‘straw mulch' (Triticum aestivum L.) and ‘living mulch’ (Lobularia maritima (L.) Desv.) were tested in combination with two alleyway groundcovers: ‘grass’ (Festuca rubra L. with Lolium perenne L.) and a legume, ‘Birdsfoot trefoil’ (Lotus corniculatus L.). The novel systems were compared with industry standards, tillage and weed fabric tree-rows with grass alleyways. Trefoil alleyway biomass deposited into tree-rows contributed an estimated 6.24 kg biomass and 0.21 kg total N/tree annually. Trefoil treatments had higher levels of organic carbon (C) and nitrogen (N), inorganic N, microbial biomass and enzyme activities, suggesting trefoil alleyways enhanced soil nutrient cycling, as well as C and N reserves in comparison to grass and tillage treatments. A functional gene array analysis was conducted to describe the mechanisms, microbial functional composition and diversity underlying the observed soil processes, however few differences were detected in soil community structure between soils under different orchard floor management. Significantly lower leaf δ15N in trees grown with trefoil compared to grass, and an association between root biomass, diameter and trunk cross-sectional area (TCSA) suggests nitrogen sources derived from the trefoil groundcover contributed to improved fruit tree vigor. Few differences resulted among orchard treatments for water use (mm/week). Trends indicated slightly higher water use in trefoil over grass, but not enough to offset observed soil quality and tree growth benefits. These findings suggest, trefoil alleyways may provide ecological benefits such as improved soil quality and efficient nutrient cycling, without substantial increases in water use.

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