Tepary (Phaseolus actifolius Gray) beans perform better than common beans (Phaseolus vulgaris) under drought conditions. The mechanism of drought tolerance in tepary bean seedlings was explored by determining the water potential (WP), osmotic potential (OP), relative water content (RWC), free sugar concentration, and the level of K ion within the expanding leaves. Two week old tepary bean seedlings were subjected to a gradual water stress with sorbitol solutions exhibiting OP values of -0.19 MPa and -0.47 MPa. Turgor remained constant whereas WP, OP and RWC declined following the stress treatment. Osmotic adjustment (OA) occurred in each treatment but the contribution of sucrose and fructose was minor. Some sorbitol was translocated to leaves and contributed to OA. The decrease of K ions in leaves indicated that these ions did not contribute to the OA. A significant decrease in cell size was observed as determined by decrease in TW/DW ratio.

The objective of this study was to determine potential propagation of Arizona sycamore (Platanus wrightii) from cuttings for use in riparian revegetation projects. Cuttings gathered from trees in Superior, Arizona during Fall 1988 and Spring 1989, and from Madera Canyon near Tucson, Arizona in Fall 1989 were treated with various concentrations of indolebutyric acid (IBA). In all studies, numbers of rooted cuttings decreased when concentrations of greater than 5,000 ppm IBA were used. Cuttings from young trunk sprouts in Fall 1988 had a higher rooting frequency than cuttings from other source trees and produced the greatest number and the longest roots in Spring 1989. In Fall 1989, plastic pots with a 1:1 perlite:vermiculite media resulted in higher rooting frequencies than when peat was incorporated into the media. While cuttings in all studies successfully rooted in the greenhouse, no plants survived outplanting on a 160 m elevation floodplain. Propagation of Arizona sycamore is more difficult than that of Fremont cottonwood (Populus fremontii) of Goodings willow (Salix goodingii) but cuttings will root with careful attention in the greenhouse.

Source: Dissertation Abstracts International, Volume: 33-07, Section: B, page: 2877. / Thesis (Ph.D.)--The Florida State University, 1972.

Source: Dissertation Abstracts International, Volume: 28-07, Section: B, page: 2682. / Thesis (Ph.D.)--The Florida State University, 1967.

No description available.

Development of a high throughput surfactant screening procedure using shikimic acid analysis

'Russet Burbank', the most important potato in North America, was described as a putative periclinal mutation from 'Burbank' and has not parented outstanding cultivars. The current study aimed to: (1) investigate the present chimeral status of NB 'Russet Burbank' based on tuber periderm phenotype, (2) determine if yield and/or processing characteristics of NB 'Russet Burbank' could be improved through selection of intraclones, (3) determine whether pre-selected somaclones had sufficient variation in protein content (crude (CP), total soluble (TSP)), or resistance to Phytophthora infestans (US-8) to select for, and (4) examine long-term stability in protein content. Somatic embryogenesis technology was used to regenerate intraclones of the NB clone of 'Russet Burbank' potato. Approx. 800 intraclones were regenerated and field-tested from 2005 to 2007. At harvest, we selected somaclones with the greatest yield compared with NB 'Russet Burbank' control. Following storage, tubers of selected clones were tested for processing quality characteristics and protein content. Late blight resistance was examined in the greenhouse for 2 years. Results showed that most intraclones had tubers with russet periderm. About 4 % of intraclones had non-russet tubers and 21 % had patchy periderm. Presently, NB 'Russet Burbank' is not organized as periclinal chimera (Nassar et al. 2008). From 2-9 % of intraclones had superior reducing sugar characteristics. Two promising somaclones with good yield and reducing sugars were selected by industry for further evaluation. Molecular characterization is now needed for advanced somaclones with improved processing features. Somatic embryogenesis technology generated sufficient somaclonal variation for potential improvement of NB 'Russet Burbank' (Nassar et al. 2009a). One advanced somaclone had greater CP content than control in 2008. One somaclone had lesser TSP content for 3 consecuti / La Russet Burbank, le cultivar de pommes de terre le plus important en Amérique du Nord, a longtemps été considérée comme dérivé d'une mutation périclinale de la 'Burbank'. Cette étude avait pour but: (1) d'évaluer le statut chimérique de la NB ' Russet Burbank' en se basant sur le phénotype péridermique des tubercules; (2) de déterminer si les caractéristiques de performance au champ et/ou de transformation peuvent être améliorées à l'aide d'une sélection d'intraclones; (3) de déterminer si les somaclones sélectionnés montrent suffisamment de variation dans leur contenu protéique (protéine brute (PB) et protéines solubles totales (PST)) ou leur résistance à Phytophthora infestans, pour permettre le triage de ces traits phénotypiques et 4) d'examiner la stabilité a long terme du contenu protéique. Environ 800 intraclones du clone NB générés utilisant la technologie d'embryogenèse somatique ont été testés au champ (2005 à 2007). Les somaclones ayant les meilleurs rendements, comparés aux témoins, ont été sélectionnés. Après l'entreposage, leurs qualités à la transformation et leur contenu protéique furent évalué. Presque tous les intraclones générés possédaient des tubercules avec des péridermes 'russet', 4% avaient des tubercules non-'russet' et 21% montraient des péridermes tachetés. La NB 'Russet Burbank' n'est pas actuellement organisé dans un arrangement périclinal chimérique (Nassar et al. 2008). Deux somaclones prometteurs ayant des rendements et des qualités de transformation améliorées fut fournis à l'industrie locale pour des évaluations futures. Suffisamment de variation entre les somaclones fut générée pour potentiellement permettre d'améliorer ce cultivar (Nassar et. al 2009a). Un somaclone possédait des teneurs en PST significativement plus faibles, comparés aux témoins, pour 3 années consécutives et 7 avaient des ten

The cost of artificial lighting is a major expense in the greenhouse production industry, especially during the winter where supplemental lighting is required to maintain production. Current technology uses broad spectrum high pressure sodium lamps (HPS), which, despite being excellent luminous sources, are not the most efficient light source for plant production. Specific light frequencies have been shown to impact photosynthesis more directly than others (especially in the red and blue ranges); focusing on specific wavelengths, light-emitting diodes (LEDs) could diminish lighting costs due to their high efficiency and lower operating temperatures. LEDs can be selected to target the wavelengths absorbed by plants, enabling the growers to customize the wavelengths of light required to maximize production and limit wavelengths that do not significantly impact plant growth. The primary purpose of this experiment was to test tomato plants (Solanum lycopersicum), in a research greenhouse using a full factorial design with three light intensities (High: 135 µmol m-2 s-1, Medium: 115 µmol m-2 s-1 and Low: 100 µmol m-2 s-1) at three red to blue ratio levels (5:1, 10:1 and 19:1) compared to 100% HPS, and a control (no supplemental lighting). The exact wavelengths chosen were 449 nm for the blue and 661 nm for the red. Secondary treatments were also tested using 100% red light supplied from the top, 100% red light supplied from the bottom, a 50%:50% LED:HPS and a replicate of the 10:1 ratio with High light intensity. The experiment was replicated over two different seasons (Summer-Fall 2011 and Winter-Spring 2011-2012). During the experiment, the highest biomass production (excluding fruit) occurred with the 19:1 ratio (red to blue), with increasing intensity resulting in more growth, whereas a higher fruit production was obtained using the 5:1 ratio. The highest marketable fruit production (fruit over 90 g, Savoura internal standard) was the 50%:50% LED:HPS, followed by 5:1 High and 19:1 High. From this research, LEDs have been shown to be superior in fruit production over HPS alone, and LEDs can improve tomato fruit production with HPS and have the ability to become the dominant supplemental greenhouse lighting system. / Le coût de l'éclairage artificiel est une dépense importante dans le secteur de la production en serre, surtout en hiver lorsqu'un éclairage supplémentaire est nécessaire pour maintenir le niveau de production. La technologie actuelle utilise des lampes à haute pression de sodium (HPS), qui en dépit d'être d'excellentes sources lumineuses, ne sont pas les sources lumineuses les plus efficaces pour la production végétale. Certaines fréquences spécifiques de lumière ont montré avoir un impact plus direct sur la photosynthèse que d'autres (en particulier dans les gammes de rouge et de bleu); en mettant l'accent sur certaines longueurs d'onde, les diodes électroluminescentes (LED) pourraient diminuer les coûts d'éclairage, en raison du rendement élevé et des températures plus basses de ce type de lampe. Les LED peuvent cibler les principales fréquences de lumière mieux absorbées par les plantes, ce qui permettrait aux producteurs de créer une lumière aux longueurs d'onde adaptées à la production optimale des plantes. Le principal objectif de cette expérience était de tester les lampes sur des plants de tomate (Solanum lycopersicum) dans une serre de recherche en utilisant un plan factoriel complet avec trois intensités lumineuses (Haute: 135 μmol m-2 s-1, Moyenne: 115 μmol m-2 s-1 et Basse: 100 μmol m-2 s-1) et trois proportions de rouge et bleu (5:1, 10:1 et19: 1), et comparer leur performance à celle de 100% HPS, et d'un contrôle (pas d'éclairage supplémentaire). Les longueurs d'onde choisies sont 449 nm (bleu) et 661 nm (rouge). Certains traitements secondaires ont également été testés, dont 100% rouge (éclairage par le haut ou le bas), un 50%:50% LED:HPS et une reproduction du 10:1 à haute intensité. L'expérience a été menée au cours de deux saisons différentes (été-automne et hiver-printemps). La production végétative la plus importante s'est produite avec le rapport 19:1 (rouge : bleu). La production de fruits était la plus élevé avec le rapport 5:1. La production en fruits commercialisables la plus importante (fruits de 90 g et plus : étalon interne de Savoura) a été pour le 50%:50% LED:HPS, suivi du 5:1 et 19:1 à haute intensité. Les LED se sont montrés supérieures aux HPS quant à la production de tomates.

Many concerns have been voiced about the impacts of non-timber forest product harvesting on forest ecosystems, prompting the development of tools for assessing harvest sustainability. The "rapid vulnerability assessment" (RVA) is one method that predicts vulnerability of plants to over-harvesting. However, there is little consensus on how to perform an RVA or interpret the results. The objective of my research is to analyze and refine the RVA method to enhance its utility. I examine factors affecting plant vulnerability used in various versions of the RVA to create a "short list" of important factors. I then use this short list of factors to perform an RVA for selected wild plant species in Huitzilac, Mexico, to further refine the RVA method. Information for this assessment comes from literature, interviews, observation, plant sampling and a town survey. Based upon these I re-conceptualize the RVA method, placing increased value on several critical factors which directly affect the availability and the rate of loss of the target species. I also suggest a method to aid in interpreting the results. Results from the case study, presented in this re-conceptualized format, indicate that none of the selected species is highly vulnerable to over-harvesting. / Plusieurs critiques ont été formulées concernant l'impacts de la collecte des produits forestiers non ligneux (PFLN) sur les écosystèmes forestiers, ce qui a mené au développement d'outils afin d'évaluer la durabilité de la sous dite collecte. L'évaluation rapide de vulnérabilité (ERV) est une méthode afin de prédire la vulnérabilité de plantes à la sur collecte. Cependant, il y a peu de consensus sur la manière optimale d'effectuer une ERV ou d'interpréter les résultats obtenus. L'objectif de ma recherche est d'analyser et de raffiner la méthode ERV afin d'augmenter son utilité pratique. J'examine des facteurs influençant la vulnérabilité des plantes utilisées dans différentes versions de l'ERV afin de créer une liste abrégée de facteurs-clés. J'utilise ensuite cette liste abrégée afin d'effectuer une ERV sur une série de plantes sauvages sélectionnées à Huitzilac, au Mexique; dans le but d'améliorer la méthode ERV. L'information pour cette ERV provient de la littérature scientifique, des entrevues, des observations directes, l'échantillonnage de plantes et une évaluation d'utilisation en ville. Basée sur ces informations, je re-conceptualise la méthode ERV plaçant plus de valeur sur plusieurs facteurs critiques qui affectent directement l'existence et le taux de perte d'espèces sélectionnées. Je suggère également une méthode afin de faciliter l'interprétation de résultats. Les résultats de l'étude de cas, présentée de forme re-conceptualisée, indiquent qu'aucune des espèces sélectionnées n'est extrêmement vulnérable à la sur-collecte.

<p> This thesis project explored the use of perennial legumes, including the non-bloating birdsfoot trefoil (BFT; <i>Lotus corniculatus</i> L.) for beef production. In 2011 and 2012, cattle averaged approximately 300 kg at the beginning of the grazing season, and approximately 450 kg in 2013. Average daily gain on pastures ranged from a low of 0.63 kg d-1 on cicer milkvetch (CMV; <i>Astragalus cicer</i> L.) in 2011 and 2013 to a high of 1.03 kg d-1 on Norcen BFT in 2013. Feedlot gains ranged from 1.14 to 1.57 kg d-1. Blood plasma fatty acids did not differ when feeding treatments were imposed, but at the end of each grazing season saturated and omega-6 fatty acids were elevated in feedlot-fed cattle compared with pasture-fed cattle, while <i>trans</i>-vaccenic acid (TVA) and omega-3 fatty acids were elevated in pasture-fed cattle. The ratio of omega-6 to omega-3 fatty acids was always higher in feedlot-fed cattle at the end of the grazing season, but in 2013, when all cattle were nearing slaughter weight, the omega-6 to omega-3 ratio was 50% higher for feedlot-fed than for BFT-fed cattle and double that of grass-fed cattle. Digestive (enteric) methane (CH4) production of beef cows was lower when cattle grazed BFT and CMV pastures (167 and 159 g CH4 per cow per d, respectively) compared to cows on meadow bromegrass (MB; <i> Bromus riparus</i> Rehmann) (355 g CH4 per cow per d). Meadow bromegrass has more fiber than legume forages, which will increase the proportion of acetate to propionate created by microbial digestion in the rumen, increasing the production and release of CH4. Perennial legume forages fix nitrogen, eliminating the need for chemical nitrogen fertilizer, and tannin-containing legumes can be grazed without risk of bloat. These forages will play an important role in developing more environmentally and economically sustainable agricultural production systems.</p>