• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 39
  • 39
  • 8
  • 4
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 152
  • 40
  • 17
  • 16
  • 15
  • 14
  • 14
  • 13
  • 11
  • 10
  • 10
  • 10
  • 9
  • 9
  • 9
  • 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.
21

Optimizing Systems for Cold-Climate Strawberry Production

Maughan, Tiffany L. 01 December 2013 (has links)
Producing fruits and vegetables in the Intermountain West can be challenging due a short growing season, extreme temperatures, and limited availability of irrigation water. This is particularly true of strawberries, where commercial production is limited due to late fall and early spring frosts that shorten the growing season. With the increasing demand for local produce as urban populations grow and as consumer buying habits change, growers are looking for ways to overcome these climatic challenges. High tunnels are one option growers can use. High tunnels are similar to greenhouses, but less expensive to construct and to maintain. Another way to protect crops against adverse climatic conditions is with low tunnels. As the name implies, they are a smaller version of a high tunnel, usually only tall enough to cover the canopy of the plant. Low tunnels can be used by themselves or in conjunction with (inside) a high tunnel. Adding heat is another option. However, heating can be expensive and may not be profitable. Targeting heat additions in the root zone may decrease cost of heat but still provide protection to the plant.These protection methods were evaluated in Cache Valley, Utah for effectiveness of increasing strawberry yield. High tunnels increased total yield, as did high tunnels used in conjunction with low tunnels. However, low tunnels by themselves were not able to increase yield in comparison to unprotected plants in the field. Targeted root zone heating was evaluated in both high and low tunnel with two target temperatures: 7 and 15 °C. There was no difference in total yield between the two temperatures, but both increased yield above the high tunnel alone and the 15 °C heating treatment moved the harvest season approximately 6.5 weeks earlier than unheated tunnels and approximately 12 weeks earlier than field production. The additional cost associated with using supplemental heat was offset by the increased yields and the higher value of early fruit.Separate experiments were carried out to determine susceptibility of strawberry leaves to damage from cold temperatures, which can then be used to provide guidelines for temperature management in high tunnels. Strawberry leaves were not significantly damaged when exposed to -3 °C, but significant damage occurred once leaves were exposed to -5 °C. To maximize the advantages of protected cultivation, growers should manage tunnels and heating to keep leaf temperatures above -3 °C. These results provide improved guidelines for growers interested in using protected cultivation strategies to provide fruit for local consumption in the Intermountain West.
22

Growing Strawberries in Home Gardens

DeGomez, Tom 06 1900 (has links)
5 pp. / Strawberries are easy to grow. They provide the first fruit of the season, and are quick to bear. When harvested fully ripe in the home garden they have excellent flavor. In stores they can be expensive and are often harvested prior to being fully ripe. Various types of strawberries are available. Each type has specific environmental requirements such as temperature and hours of daylight for good production. With the wide range of climatic zones in Arizona it is important to choose the right type of strawberry for your growing conditions.
23

Strawberry handling in Quebec

Lepine, Yves January 1988 (has links)
No description available.
24

Alternativas no controle fitossanitário em diferentes cultivares de morangueiro como ferramenta na produção integrada

Pallamin, Maria Lúcia [UNESP] 23 August 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-23Bitstream added on 2014-06-13T20:55:02Z : No. of bitstreams: 1 pallamin_ml_me_botfca.pdf: 2330850 bytes, checksum: ede30ea107bdcae07d99d32fdfd9459f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho teve por objetivo, obter maiores informações sobre o desenvolvimento de quatro cultivares de morangueiro (Dover, Oso Grande, Camarosa e Sweet Charlie), na região de Bauru - SP, submetidos a sistemas fitossanitários alternativos, como ferramenta na Produção Integrada do Morangueiro (PIMO). Avaliou-se aspectos de produtividade (peso e número de frutos); qualidade (teor de sólidos solúveis totais, acidez titulável, pH, vitamina C e textura) e monitoramento de pragas e doenças. O plantio foi realizado em abril de 2005 sobre plástico preto, no espaçamento de 25 x 25 cm, totalizando-se 20 plantas por parcela. O delineamento estatístico foi em blocos casualizados utilizando-se um esquema fatorial em parcelas subdivididas, no qual o fator principal conteve dois modelos de tratamentos fitossanitários e para o fator secundário, as quatro cultivares de morangueiro. Nos dois modelos de tratamentos foram utilizados agroquímicos convencionais da grade PIF para Morango na fase vegetativa (abamectina e tebuconazol), diferenciando-se para a fase reprodutiva; Modelo PIF 1: tratamento com calda viçosa, super magro, Microgeo (2%) e enxofre e Modelo PIF 2: tratamento com calda bordalesa, super magro, éster de ácido graxo (GOC 109) (5%) e enxofre. Os dados obtidos foram submetidos à análise de variância e as médias comparadas através do Teste de Tukey a 5% de probabilidade. A cultivar Dover apresentou maior produtividade média e número médio de frutos independente do sistema de produção; textura mais firme e menor ratio (sabor) indicando maior aptidão para a indústria. A XI cultivar Oso Grande destacou-se positivamente na produção de frutos graúdos, firmeza e sabor, aspectos importantes para o consumidor e comercialização. Sweet Charlie apresentou excelente características de sabor e vitamina C... / The present work had for objective, to obtain more information about the development of four strawberry cultivars ( Dover, Oso Grande, Camarosa and Sweet Charlie), in Bauru - SP, submitted to alternative phytosanitary systems, as tool for the Integrated Strawberry Production. Aspects of productivity (weigh and number of fruits); quality (total soluble solids, titrable acidity, pH, vitamin C and firmness) and pest and disease monitoring were evaluated. The planting was accomplished in April of 2005 over mulching, the spacing of 25 x 25 cm was adopted being totaled 20 plants by plot. Experimental design used was of randomized blocks in factorial scheme of split plots with the main factor contained two models of phytosanitary treatment and for the secondary factor, the four strawberry cultivars. Conventional agrochemicals (abamectin and tebuconazol) registered for this culture in Brazil, were used for both models of treatment, in the vegetative phase. For the reproductive phase; Model PIF 1: treatment with Viçosa mixture, biofertilizer Supermagro, Microgeo (2%) and sulfur; and Model PIF 2: treatment with Bourdeaux mixture, biofertilizer Supermagro, fatty acid ester (GOC 109) (5%) and sulfur. The data were submitted to a variance analysis and the average compared to Tukey's Test at 5% of probability. 'Dover' presented larger medium productivity and medium number of fruits independent of the production system; firmer texture and smaller ratio (flavor) indicating larger aptitude for the industry. 'Oso Grande' stood out positively in the production of great fruits, firmness and flavor, important aspects for the consumer and commercialization. Sweet XIII Charlie' presented excellent flavor characteristics and vitamin C, demonstrating an aptitude for in natura consumption. There were not significant differences among the employed production... (Complete abstract click electronic access below)
25

Strawberry handling in Quebec

Lepine, Yves January 1988 (has links)
No description available.
26

Seed germination, kanamycin sulfate selection, and the influence of nitrogen treatments on an insertional mutant population of Fragaria vesca

Lindsay, Robert Clark 18 January 2011 (has links)
With the goal of creating faster and more efficient methods of generating unique Ac/Ds insertional mutants in a population of Fragaria vesca, various methods of seed germination, kanamycin screening, and the effects of varying nitrogen fertilization on diploid strawberry have been examined. Seed germination was improved to 42% in B5 liquid medium compared to _ on MS solid medium. Kanamycin screening during germination was most effective in liquid B5 medium as well. A readily discernable phonotypic difference between sensitive (necrotic radical) and resistant (branched roots) seedlings was observed in the B5 liquid medium and the frequency of escapes was reduced from __ on solid MS to __ in liquid B5. Although there were few phenotypic differences due to nitrogen application over the tested treatments (25-300 ppm) runner initiation was suppressed and chlorophyll was increased in the high (300 ppm) nitrogen treatment. There was limited evidence to suggest an increased rate of transposition in the high (300 ppm nitrogen) treatment level compared to those plants receiving lower levels of nitrogen. The selection efficiency and greater germination of the B5 liquid medium over MS medium would be expected to reduce the cost of screening thousands of seedlings because of the need for fewer disposables and medium transfers during the 5 week germination process. The use of B5 liquid medium, as well as treating plants with high levels of nitrogen (300 ppm), may be facilitate high throughput production of transposon tagged mutants in a population of F. vesca. / Master of Science
27

The effect of maleic hydrazide in controlling plant populations in the strawberry in southwest Virginia

Gingras, Rene Joseph 28 July 2010 (has links)
The effects of Maleic Hydrazide (MH) in controlling strawberry plant populations were studied. Foliar applications of MH at 1000 ppm resulted in reduced runner length. The effect of MH sprays appeared to be directly related to the stage of rooting at the time of spray applications. Rooted plants were affected less than non-rooted plants. By the end of the growing season (Oct. 31) plant populations were significantly less than the control (matted row) and equaled that of a hand thinned treatment. Sprayed and hand-pruned plots were significantly lower in yield and fruit number. Berry size was the same for all treatments. / Master of Science
28

Effect of nutrition on postharvest quality and grey mould development in strawberries.

Naradisorn, Matchima January 2008 (has links)
Strawberries are an extremely perishable fruit mainly due to their soft texture and sensitivity to fungal infection. The fungal pathogen Botrytis cinerea is responsible for grey mould on strawberries and is the main causal agent of postharvest decay and subsequent economic loss. As an alternative to fungicides, manipulation of plant nutrition, such as calcium and boron, has been suggested as a means of disease management. This project investigated the effects of calcium and boron application on fruit quality and grey mould development in strawberry. The effect of calcium on fruit quality, grey mould development and leaf blight in strawberry cultivars ‘Aromas’ and ‘Selva’ was investigated through preharvest and postharvest applications. To determine the effect of preharvest application, calcium sulphate in 0.25X strength Hoagland’s solution was applied at 0, 100, 300 and 500 ppm Ca through fertigation. Fully-ripened fruit were harvested and evaluated for postharvest quality at harvest and then after storage at 10⁰C, 90±5% RH for 2 to 10 days. Although fruit firmness of both cultivars declined slightly during storage, this was not affected by preharvest calcium application. Similarly, preharvest calcium treatment had no effect on the external appearance, pH, soluble solids content (SSC) or titratable acidity (TA). No grey mould development was observed on fruit at harvest when flowers were inoculated with a conidia suspension of B. cinerea (10⁴ conidia per mL). However, fruit harvested from plants that received calcium at any concentration had less incidence of grey mould during storage at 10⁰C, 90±5% RH for 14 days than fruit harvested from plants that received no calcium for both cultivars. For ‘Aromas’, 79% and 51% of fruit, and for ‘Selva’, 69% and 43% of fruit, showed rot when treated with 0 and 500 ppm Ca, respectively. The shelf life of ‘Aromas’ and ‘Selva’ increased by about 8% when plants received 500 ppm Ca in comparison with plants that received 0 ppm Ca. After 7 days of incubation at 22 to 24⁰C, there was no difference between blight lesions on wound-inoculated detached leaves from different calcium treatments for either cultivar. However, the lesions on ‘Selva’ were smaller than on ‘Aromas’. The calcium levels in leaves from plants that received calcium at any concentration were adequate for strawberry growing and significantly higher (P < 0.05) than in leaves from plants that received 0 ppm Ca. However, calcium treatment did not ensure transfer of calcium to fruit tissues. Calcium lactate and calcium chloride were used as postharvest calcium treatments at 1500, 3000 and 4500 ppm Ca. Fruit of ‘Selva’ were dipped in calcium solution for 5 min and wound-inoculated with B. cinerea (10⁶ conidia per mL). Calcium lactate and calcium chloride at 3000 and 4500 ppm Ca, respectively, were most effective in delaying Botrytis rot development on ‘Selva’ after 7 days of storage at 10⁰C, 90±5% RH. Storage for least 24 h after calcium dips prior to inoculation was required to delay the development of fruit rot. Fruit harvested early in the season seemed to be less susceptible to grey mould than those harvested later. However, calcium treatment tended to be more effective when applied to late-season fruit. Preharvest boron treatment, applied as for calcium but at 0, 0.25, 0.5 and 1.0 ppm B, had no effect on fruit firmness of either cultivar. However, firmness of ‘Aromas’ fruit was slightly greater than ‘Selva’ fruit for all treatments. The amount of boron applied had no effect on the external appearance, pH, SSC or TA for either cultivar after storage of fruit for up to 10 days. Application of boron had no effect on fruit grey mould development in either cultivar. Furthermore, boron had minimal effect on the incidence of blight on woundinoculated detached leaves of ‘Aromas’ 7 days after inoculation. However, blight lesion diameters on ‘Selva’ leaves in the 1.0 ppm B treatment (8.0 mm) were significantly smaller (P < 0.001) than in the 0 ppm B treatment (13.0 mm). Phytotoxicity was observed in boron treatments even at the level considered optimum for strawberry growing. Severity increased with increasing boron concentration but no consistent effect on flower death or flower abortion was observed. In conclusion, strawberry is sensitive to boron toxicity. Calcium may enhance fruit firmness and, consequently, delay grey mould development if calcium penetrates the fruit. Postharvest calcium treatment tended to be more effective in delaying development of grey mould when applied to late-season fruit. Calcium lactate is a potential alternative to calcium chloride for reducing decay caused by B. cinerea in strawberry without providing undesirable bitterness. This finding may provide a basis for application in industry. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1331382 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine 2008
29

Temperature-dependent development of strawberry root weevil Otiorhynchus ovatus (L.)

Umble, Jon R. 02 June 1999 (has links)
The temperature-dependent development of pupae and adults of strawberry root weevil (SRW) Otiorhynchus ovatus (L.) was studied in strawberry (Fragaria x ananassa Duch. var. 'Totem'). The development of pupae and adults was investigated at constant temperatures from 3-33��C at 3��C intervals. Major emphasis was on the development of a weighted linear temperature-based pupal prediction model. The predictive ability of this weighted model was compared to a traditional non-weighted linear degree-day model by relating predictions to the observed occurrence of SRW lifestages determined by field sampling. The upper thermal lethal limit for SRW pupae was between 30 and 33��C. Pupae did not eclose below 6��C. Mean pupal duration was 127 d at 6��C and 7 d at 30��C. Rate of development (1/days) was greatest at 30��C. The weighted linear pupal prediction model produced a developmental threshold of 4.3��C and a degree-day requirement of 227.3. The non-weighted linear pupal prediction model produced a developmental threshold of 6.2��C and a degree-day requirement of 163.9. Adults fed at all temperatures from 3-33��C and oviposited at temperatures between 18 and 30��C . The longest preoviposition period (32.8 d) and the least total number of eggs (2.2) were observed at 18��C. The shortest preoviposition period (15.1 d) and the greatest total number of eggs (282.5) were observed at 27��C. A temperature range of 21 to 27��C appeared to be optimum for oviposition; i.e. relative to other temperatures, preoviposition time was short, mortality was low, and total number of eggs laid was high. / Graduation date: 2000
30

Effect of nutrition on postharvest quality and grey mould development in strawberries.

Naradisorn, Matchima January 2008 (has links)
Strawberries are an extremely perishable fruit mainly due to their soft texture and sensitivity to fungal infection. The fungal pathogen Botrytis cinerea is responsible for grey mould on strawberries and is the main causal agent of postharvest decay and subsequent economic loss. As an alternative to fungicides, manipulation of plant nutrition, such as calcium and boron, has been suggested as a means of disease management. This project investigated the effects of calcium and boron application on fruit quality and grey mould development in strawberry. The effect of calcium on fruit quality, grey mould development and leaf blight in strawberry cultivars ‘Aromas’ and ‘Selva’ was investigated through preharvest and postharvest applications. To determine the effect of preharvest application, calcium sulphate in 0.25X strength Hoagland’s solution was applied at 0, 100, 300 and 500 ppm Ca through fertigation. Fully-ripened fruit were harvested and evaluated for postharvest quality at harvest and then after storage at 10⁰C, 90±5% RH for 2 to 10 days. Although fruit firmness of both cultivars declined slightly during storage, this was not affected by preharvest calcium application. Similarly, preharvest calcium treatment had no effect on the external appearance, pH, soluble solids content (SSC) or titratable acidity (TA). No grey mould development was observed on fruit at harvest when flowers were inoculated with a conidia suspension of B. cinerea (10⁴ conidia per mL). However, fruit harvested from plants that received calcium at any concentration had less incidence of grey mould during storage at 10⁰C, 90±5% RH for 14 days than fruit harvested from plants that received no calcium for both cultivars. For ‘Aromas’, 79% and 51% of fruit, and for ‘Selva’, 69% and 43% of fruit, showed rot when treated with 0 and 500 ppm Ca, respectively. The shelf life of ‘Aromas’ and ‘Selva’ increased by about 8% when plants received 500 ppm Ca in comparison with plants that received 0 ppm Ca. After 7 days of incubation at 22 to 24⁰C, there was no difference between blight lesions on wound-inoculated detached leaves from different calcium treatments for either cultivar. However, the lesions on ‘Selva’ were smaller than on ‘Aromas’. The calcium levels in leaves from plants that received calcium at any concentration were adequate for strawberry growing and significantly higher (P < 0.05) than in leaves from plants that received 0 ppm Ca. However, calcium treatment did not ensure transfer of calcium to fruit tissues. Calcium lactate and calcium chloride were used as postharvest calcium treatments at 1500, 3000 and 4500 ppm Ca. Fruit of ‘Selva’ were dipped in calcium solution for 5 min and wound-inoculated with B. cinerea (10⁶ conidia per mL). Calcium lactate and calcium chloride at 3000 and 4500 ppm Ca, respectively, were most effective in delaying Botrytis rot development on ‘Selva’ after 7 days of storage at 10⁰C, 90±5% RH. Storage for least 24 h after calcium dips prior to inoculation was required to delay the development of fruit rot. Fruit harvested early in the season seemed to be less susceptible to grey mould than those harvested later. However, calcium treatment tended to be more effective when applied to late-season fruit. Preharvest boron treatment, applied as for calcium but at 0, 0.25, 0.5 and 1.0 ppm B, had no effect on fruit firmness of either cultivar. However, firmness of ‘Aromas’ fruit was slightly greater than ‘Selva’ fruit for all treatments. The amount of boron applied had no effect on the external appearance, pH, SSC or TA for either cultivar after storage of fruit for up to 10 days. Application of boron had no effect on fruit grey mould development in either cultivar. Furthermore, boron had minimal effect on the incidence of blight on woundinoculated detached leaves of ‘Aromas’ 7 days after inoculation. However, blight lesion diameters on ‘Selva’ leaves in the 1.0 ppm B treatment (8.0 mm) were significantly smaller (P < 0.001) than in the 0 ppm B treatment (13.0 mm). Phytotoxicity was observed in boron treatments even at the level considered optimum for strawberry growing. Severity increased with increasing boron concentration but no consistent effect on flower death or flower abortion was observed. In conclusion, strawberry is sensitive to boron toxicity. Calcium may enhance fruit firmness and, consequently, delay grey mould development if calcium penetrates the fruit. Postharvest calcium treatment tended to be more effective in delaying development of grey mould when applied to late-season fruit. Calcium lactate is a potential alternative to calcium chloride for reducing decay caused by B. cinerea in strawberry without providing undesirable bitterness. This finding may provide a basis for application in industry. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1331382 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine 2008

Page generated in 0.0434 seconds