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Showing 1 to 20 of 136 for “"Lettuce"”.
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Consumers’ Willingness to Pay for Hydroponic Lettuce
… begun using hydroponic techniques to grow leaf lettuce and other food crops in a controlled environment. Recent controversy about the ongoing inclusion of hydroponics in the USDA organic program has highlighted uncertainty about marketing for hydroponic crops. In November 2017, the National …
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THE GENETICS OF ESTERASE ISOZYMES IN LETTUCE CULTIVARS.
Lettuce, in its cultivated form (Lactuca sativa L.), is a crop of economic importance with several characteristics which make it well suited for biochemical and genetic studies. Biochemical traits such as proteins and enzymes have been studied extensively in many plant species and constitute an …
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Wild lettuce as a source of natural rubber
… content presented in condensed form. Filed lettuce of the specie Lactuca scariola was investigated to determine its place among the other rubber-bearing plants. Nearly pure stands of natural growing wild lettuce were harvested and the weights of plant material determined. Yields up to 2,830 …
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Dynamic Environmental Control of a Vertical Farm for Lettuce Production
… Fresh and dry shoot masses of red colored lettuce (Lactuca sativa L. cv. ‘Rouxaï’), along with light use efficiency and electrical use efficiency, were used to evaluate the proposed dynamic light control strategies for growth, while anthocyanin concentration, tipburn severity score, and …
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Effects of Food Safety Events on U.S. Romaine Lettuce Prices
Romaine lettuce and leafy greens have been at the center of food safety concerns over the last several years. More specifically, romaine lettuce has been directly linked to seven(7) foodborne illness outbreaks and resulted in five(5) recalls over the eight(8) years period of January 1, 2012, to …
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Cheeseweed (Malva Parviflora L.) Competition with Cabbage and Lettuce on Maui, Hawaii
… One experiment was conducted with transplanted lettuce and cheeseweed sown to densities from 1 to 15 weeds per 0.1 m2. The relationship between trimmed lettuce head fresh weights in grams (y) and the number of weeds per 0.1 m2 (x) was best expressed by the linear equation y = 842 - 49.4x. When y …
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Nitrate accumulation in hydroponically-grown lettuce cultivars and relationship to nitrogen supply
… and reduction in hydroponically-grown lettuce (Lactuca sativa L.), and its relationship to various aspects of N supply, including solution NO$\sb{3-}$ concentration, the nitrate:ammonium solution ratio, and the interaction between solution flow rate and NO$\sb{3-}$ fertilization level.
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Treatment of post hydrothermal liquefaction wastewater and suitability for hydroponic lettuce production
… treatments of PHWW and investigating whether lettuce can be hydroponically growth with sufficient nutrients and safe for heavy metals and E.coli/coliforms. For different treatment combinations of PHWW dilution factor, filtration type, and nitrification reaction, the results indicate that …
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Mechanisms Associated with Attachment of Escherichia coli O157:H7 to Lettuce Surfaces
… pathogens to fruits and vegetables. Using lettuce as a model, the attachment of Escherichia coli O157:H7 to produce surfaces was studied. Strains expressing various extracellular proteins (curli, O157-antigen, and intimin) known to influence attachment of E. coli to intestinal cells were …
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Inheritance of Resistance to Tomato Spotted Wilt Virus in Lettuce (Lactuca Sativa L.)
… range, has become a major limiting factor in lettuce production in Hawaii. Symptoms of this disease on lettuce are necrotic spotting of young leaves, stunting, wilting, and death of the plant. The large host range of this disease has made it difficult to control. Genetic resistance might work, …
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Physiological Studies on Nitrate Absorption and Accumulation in Lettuce (Lactuca Sativa L.) Genotypes
Made available in DSpace on 2014-12-16T20:45:20Z (GMT). No. of bitstreams: 1 8908684.pdf: 4598257 bytes, checksum: 01a6e2bf3309b072975d1d75575f467c (MD5) Previous issue date: 1988
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The effects of growth salinity and irradiance on thylakoid stacking in lettuce plants
… altered the degree of thylakoid stacking in lettuce plants. Furthermore, we established that growth salinity and irradiance interacted in such a way that the moderate salinization of the nutrient solution was associated with less stacking at high irradiances and more stacking at low …
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Optimizing Hydroponic Lettuce Yield: Evaluation of Potassium Source and Concentration with Plant Imaging
… is an expanding industry in the United States. Lettuce (Lactuca sativa) possesses considerable economic importance as one of the foremost leafy vegetables worldwide in terms of financial value for production in CEA. Rapid growth rate, high yield, and potential return further enhance its …
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Aeroponic System Optimization for Butterhead Lettuce Growth and Future Sustainability Using Flow Blurring Atomization
… aeroponic system by growing butterhead lettuce over a span of 12 days under controlled conditions. After conducting three experiments, the findings indicated that the droplet range of 64 𝜇m to 82 𝜇m experienced the most growth under the reported test conditions by evaluating the change …
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The influence of transplanting depth of head lettuce on size and shape of head
… on the size and shape of head of crisp-head lettuce. A hotbed experiment was conducted in the winter of 1950-1951. A greenhouse experiment was conducted in the spring and early summer of 1951. A final experiment, which was a modification of the other two, was conducted in the field in the …
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Effect of airflow and carbon dioxide on growth, yield, and gas exchange of lettuce
Romaine lettuce (Lactuca sativa var. longifolia L.) was grown hydroponically inside a walk-in growth chamber (Conviron, PGW36) with two levels of airflow (0.36 and 2.50 m$\rm\cdot s\sp{-1})$ at different atmospheric CO$\sb2$ concentrations (350 and 700 $\rm\mu mol\cdot mol\sp{-1}).$ A combination …
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