Arugula Crop Production in Arid and Semi-Arid Regions: Nutritional Value, Postharvest Quality, and Sustainability in Controlled Environments

Persistent Link:
http://hdl.handle.net/10150/195968
Title:
Arugula Crop Production in Arid and Semi-Arid Regions: Nutritional Value, Postharvest Quality, and Sustainability in Controlled Environments
Author:
Hamilton, Jeffrey Muir
Issue Date:
2009
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Plant responses to abiotic stress are neither singular nor linear. The research represented within this dissertation was intended to evaluate selected biochemical and physiological responses in two Arugulas (Images 1-5), to agronomic interventions designed to mitigate extreme environmental abiotic factors, characteristic of arid agricultural production regions. Plant stress responses were investigated under field conditions and within controlled environments (CE), during the course of a preliminary trial and three independent studies, all four directly related. The preliminary trial evaluated harvest and postharvest nutritional content (i.e., antioxidants) of two Arugulas, Eruca sativa (L.) Cav. ssp. sativa (P. Mill.) and Diplotaxis tenuifolia (L.) DC cv. Sylvetta; grown under field conditions in the semi-arid upper Sonoran Desert. In this trial, we defined baseline harvest and postharvest antioxidant values for the Arugulas, cultivated in a semi-arid environment. The initial study, conducted within a CE utilizing a water recycling system, evaluated changes in the nutritional value of three specialty leafy cruciferous vegetables: D. tenuifolia, E. sativa and Lepidium sativum; when subjected to increasing salinity levels in the nutrient solution. It was concluded that, when specific Crucifers are irrigated with moderately high levels of salinity, neither harvest nor postharvest nutritional values are compromised. The second study, investigated the response of a suite of plant physiological parameters (e.g., yield and photosynthetic rate) in the three Crucifers to salinity, within the CE. This research provided guideline salinity values where yields did not decline, and encourages growers to consider water resources compromised by salinity and nutrient solution recycling. During the third study, the influence of environmental conditions on the nutritional content in leafy vegetables, prevalent immediately before harvest, was investigated; by subjecting plants to reduced sunlight treatments and early irrigation termination. We observed that, modulating light intensity late in the season, and early irrigation termination strategies, modify the nutritional content of leafy vegetables; and potentially the subsequent postharvest shelf life. Collectively evaluated, this research suggests that simple agronomic interventions are valuable, yet practicable, tools that can enhance the nutritional content of specialty vegetables, in arid regions: be that intervention an imposed controlled-stress, utilizing nutrient recycling systems within a CE, or basic light-reduction and irrigation termination strategies within conventional fields systems.
Type:
text; Electronic Dissertation
Keywords:
Arugula; controlled environment; Diplotaxis tenuifolia; Eruca sativa; phenolics; salinity stress
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Arid Lands Resource Sciences; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Fonseca, Jorge M.
Committee Chair:
Fonseca, Jorge M.

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titleArugula Crop Production in Arid and Semi-Arid Regions: Nutritional Value, Postharvest Quality, and Sustainability in Controlled Environmentsen_US
dc.creatorHamilton, Jeffrey Muiren_US
dc.contributor.authorHamilton, Jeffrey Muiren_US
dc.date.issued2009en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractPlant responses to abiotic stress are neither singular nor linear. The research represented within this dissertation was intended to evaluate selected biochemical and physiological responses in two Arugulas (Images 1-5), to agronomic interventions designed to mitigate extreme environmental abiotic factors, characteristic of arid agricultural production regions. Plant stress responses were investigated under field conditions and within controlled environments (CE), during the course of a preliminary trial and three independent studies, all four directly related. The preliminary trial evaluated harvest and postharvest nutritional content (i.e., antioxidants) of two Arugulas, Eruca sativa (L.) Cav. ssp. sativa (P. Mill.) and Diplotaxis tenuifolia (L.) DC cv. Sylvetta; grown under field conditions in the semi-arid upper Sonoran Desert. In this trial, we defined baseline harvest and postharvest antioxidant values for the Arugulas, cultivated in a semi-arid environment. The initial study, conducted within a CE utilizing a water recycling system, evaluated changes in the nutritional value of three specialty leafy cruciferous vegetables: D. tenuifolia, E. sativa and Lepidium sativum; when subjected to increasing salinity levels in the nutrient solution. It was concluded that, when specific Crucifers are irrigated with moderately high levels of salinity, neither harvest nor postharvest nutritional values are compromised. The second study, investigated the response of a suite of plant physiological parameters (e.g., yield and photosynthetic rate) in the three Crucifers to salinity, within the CE. This research provided guideline salinity values where yields did not decline, and encourages growers to consider water resources compromised by salinity and nutrient solution recycling. During the third study, the influence of environmental conditions on the nutritional content in leafy vegetables, prevalent immediately before harvest, was investigated; by subjecting plants to reduced sunlight treatments and early irrigation termination. We observed that, modulating light intensity late in the season, and early irrigation termination strategies, modify the nutritional content of leafy vegetables; and potentially the subsequent postharvest shelf life. Collectively evaluated, this research suggests that simple agronomic interventions are valuable, yet practicable, tools that can enhance the nutritional content of specialty vegetables, in arid regions: be that intervention an imposed controlled-stress, utilizing nutrient recycling systems within a CE, or basic light-reduction and irrigation termination strategies within conventional fields systems.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectArugulaen_US
dc.subjectcontrolled environmenten_US
dc.subjectDiplotaxis tenuifoliaen_US
dc.subjectEruca sativaen_US
dc.subjectphenolicsen_US
dc.subjectsalinity stressen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineArid Lands Resource Sciencesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorFonseca, Jorge M.en_US
dc.contributor.chairFonseca, Jorge M.en_US
dc.contributor.committeememberHutchinson, Charles F.en_US
dc.contributor.committeememberMarsh, Stuarten_US
dc.contributor.committeememberOttman, Michael J.en_US
dc.identifier.proquest10685en_US
dc.identifier.oclc659753444en_US
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