Two varieties of Pisum sativum, L, Jade and Olympic, were grown for a period of four weeks from seeding, under constant light intensity and diurnally fluctuating temperatures, while being subjected to varying-artificially induced-degrees of nutrient stress. Net carbon dioxide exchange rates were measured in order to determine the influence of excess or deficient nitrogen and phosphorus concentrations within the nutrient medium. Carbon dioxide assimilation rates, under various degrees of nutrient stress were highly variable, both within the same variety and between varieties tested. Microchemical determinations of chlorophylls a and b, and of inorganic phosphate, nitrate and nitrite were carried out in order to determine the relationship of some physiological aspects of mineral deficiency to carbon dioxide assimilation. Investigations as to changes in stomatal index (I) as a result of nutrient stress also showed a large amount of variation. Results obtained indicated that variety Jade was very sensitive to nitrogen deficiency within the rooting medium, as evidenced by a large increase in stomatal index values with nitrogen deficiency. Olympic showed a greater sensitivity to phosphorus deficiency than did Jade. Neither total chlorophyll content, nor chlorophyll a/b ratio appeared to exert any deciding influence upon net carbon dioxide assimilation. A relationship appeared to exist between CO₂ assimilation and quantities of nitrate and/or nitrite present within the photosynthetic tissues of plants tested. This experiment was unable to fully explain the reason(s) for the great degree of variability of net CO₂ exchange rates extant even between plant specimens growing in the same nutrient medium. Some technical improvements applicable to the present experiments as well as some alternative experimental procedures are discussed. / Land and Food Systems, Faculty of / Graduate

This study was undertaken to examine the growth responses of various annual plant species on serpentine and non-serpentine soils from the Sierra Nevada foothills and the adjacent area. Various measurements were taken at intervals during the life cycle to determine the comparative growth patterns on different types of soil. These measurements indicate the degree of serpentine tolerance and intolerance.

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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.

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Thesis (MTech (Horticultural Science))--Cape Peninsula University of Technology, 2016. / Hydroponics, i.e. plant cultivation in mineral-rich water is a synergy between plant, human, and machine. For decades the hydroponic garden has been offered on horticultural markets, and was repeatedly innovated to better meet consumer horticultural needs. Currently, platform convergences with electronic control systems can possibly enable more efficient products for direct consumer hydroponic cultivation. This means that, like many appliances in the home; hydroponic plant cultivation can become somewhat automated. Marketing and product innovation can help calibrate optimal New Product Development NPD of hydroponic gardens for people. The literature review grasps how consumers are subjected to a changing environment together with changing technology such as hydroponics, plant nutrition, and even garden automation. Market research frameworks namely Morphological Analysis (MA) and Conjoint Analysis (CA) are the tools deployed here for profiling and prioritising these products for horticultural consumers. Firstly, a qualitative analysis identifies conceptual sets for structures, inputs, and controls, which all harmonise into new intersections cultivation, hydroponics, and automation and the e-garden concepts. The MA next produces, and organises secondary data into constraints for the CA. Here, general hydroponic cultivation is first decomposed into all its many component parts which collectively describe the whole, where these parts are then classed along various attributes namely: garden plane xA, automation xB, performance xC, organics xD, and price xE So garden plane is composed of level and vertical gardens, garden automation is composed of manual and automatic gardens, garden performance is composed of casual and high-performance gardens, garden organics is composed of non-organic and organic gardens, and garden price although quantitative is simply composed of R2500 and R5000. These classes of attributed data can now become treated as categorical factors using indicator or dummy variables. Secondly, the CA determines how these attributes are most preferred by horticultural consumers at garden centre clusters. This involves measuring respondent preferences levels, to compute the part-worth utility for each attribute found in the MA. Factors such as garden organics, price, and automation hold adjusted alpha significance. Mainly, garden organics contributed to response effects, while price has negative slope and is second, while automation comes third. A combination of garden automation and organics is found to optimise consumer utility for Hydroponic Garden(s) HG.This research illuminates how horticultural consumers may prefer various HG, by understanding HG and how they can better benefit these people.

Typescript (photocopy) / vi, 271 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Botany, 1982

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