Thesis (M.S.)--Oregon State University, 1963. / Typescript. Includes bibliographical references (leaves 89-93). Also available on the World Wide Web.

Plant transformation provides a promising methodology of introducing new genes that encode desirable traits to a wide range of crop plants. Success in genetic transformation has been achieved in many of the important crop species, such as soybean, cotton, rice, corn. However, wheat, one of the major crops of the world, has been considered to be difficult to transform via either Agrobacterium or biolistic bombardment (Rakszegi et al., 2001). There have been limited studies on A. tumefaciens-mediated transformation of cereals, including wheat, because of the overall refractory character of host-pathogen interactions between Agrobacterium and the cereal plants (Gould et al., 1991; Hiei et al., 1994; Cheng et al., 1997). While the genetic transformation of rice using Agrobacterium has become routine, only a few successful studies of Agrobacterium- mediated transformation of wheat have been reported, and these involved a model spring wheat, Triticum aestivum cultivar Bobwhite (Cheng et al., 1997). Model genotypes are developed for ease of plant regeneration in tissue culture and both Agrobacterium and biolistic mediated transformation methods require regeneration of plants in tissue culture. More success has been achieved in obtaining fertile transgenic wheat plants by particle bombardment, or biolistics method (Vasil et al., 1992; Weeks et al., 1993; Becker et al., 1994; Zhou et al., 1995; Altpeter et al., 1996). Wheat plants of the model system cultivar Bobwhite were used in most of these studies as well. The primary objective of this study was to use the callus-based transformation procedures mentioned above with a non-model cultivar of hexaploid spring wheat Saratovskaya-29, widely grown in Kazakhstan, to test the genotype dependence of the previously developed transformation protocols with respect to stable transfer of DNA and regeneration of transgenic plants. The spring wheat cultivar Saratovskaya-29 (Albidum-24/ Lutescens-55-11) was chosen for the study as being one of the most widely grown wheat cultivars both in Russia and Kazakhstan. It was bred in early 50??s in the Research Institute of the South-East, Saratov. Because of its drought resistance and good baking quality traits, Saratovskaya-29 reached a peak of nearly 21.2 mln ha in the former USSR in 1996 (Martynov and Dobrotvorskaya, 1996). Economical importance of this cultivar makes it an appropriate candidate for further improvement of economically significant traits. Another objective of the study described was to compare the transformation efficiencies and inheritance in the transgenic plants produced.

Proefschrift--Utrecht. / "Stellingen": p. [143]-144. "Litteratuuroverzicht": p. [129]-137.

Proefschrift--Utrecht. / "Stellingen": p. [143]-144. "Litteratuuroverzicht": p. [129]-137.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1960. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 262-279).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1964. / Typescript. Vita. Includes bibliographical references (leaves 171-179).

Limb lengthening procedures use fixation devices to extend the constantly regenerating bone and surrounding soft tissues. Automated devices have been developed that aim to provide a more gradual tissue extension, resulting in better quality of treatment for the patient. Benefits include pain reduction and probable enhanced tissue outcomes. The development of one such new smart lengthening device is described. An integrated numerical model of tissue mechanics during lengthening is presented. It represents the mechanical environment in which the devices extend. The mechanism of the automated device is also modelled using Matlab software and validation was achieved through experimental testing. Validation of the tissue model includes the design of an experimental hydraulic system with the ability to control the peak loads and relaxation over time. A simplified mechanobiological model for the longer term healing effects is proposed. Calibration of the tissue model to clinical data allows for direct comparison of the load and extension of identical tissues, one being lengthened by a traditional device, the other an automated device. This simulation can be extended to include a range of lengthening rates and frequencies of distraction alongside various patient dependent tissue properties. The models also provide the opportunity to assess the effects of iterative changes to the device parameters (such as stiffness) on its performance as well as analyse the effect that these changes have on tissue extension and loading. Use of these models to optimise the device design alongside optimisation of the extension regime can result in improved device design and consequently improved patient outcomes.

Milk thistle, Silybum marianum L. Gaertn., is a source of flavonoid taxifolin and flavonolignans - silymarin complex (silybin, silydianin, silycristin and isosilybin). Milk thistle is usually obtained by field cultivation. Alternative way for getting the active components, is the use of in vitro cultures. But the production of secondary metabolites by the in vitro cultures is low in comparison with plant. One of the possibilites how to increase this produciton is the method of elicitation. In this study, ethephon as the elicitor, in the concentrations of 500 µmol/l, 400 µmol/l, 200 µmol/l, 100 µmol/l and 50 µmol/l was used with the aim to increase secondary metabolite production in suspension and callus cultures. The effect of ethephon was compared to its inhibitor (AgNO3, 120 µmol/l). The levels of flavonolignans and taxifolin were measured by the method of HPLC. The samples were taken 24, 48, 72, 96 and 168 hours after the ethephon application and inhibitor treatment. The nutrient medium of suspension culture was also tested for the possibity of secondary metabolites releasing into medium. The highest content of flavonoid taxifolin was found in the suspension culture medium after 48 h treatment with ethephon in conc. of 400 µmol/l. The level of taxifolin was increased by 197-fold to 1,97 mg/100...

Genista tinctoria, family Fabaceae, is a potent source of isoflavonoids (genistin, genistein, daidzein, formononetin, biochanin A) with a wide spectrum of potential medical impact. Genista also contains quinolizidin alkaloids (cytisin, anagyrin, lupanin, spartein, etc.), which are toxic. The reason why in vitro cultures are used is an absence of toxic alkaloids production and higher yield of isoflavonoids in comparison with intact plant. For an increase of isoflavonoid production method of elicitation is beeing used. Isoflavonoids are studied for their phytoestrogenic effects, for which they could be used in treatment of postmenopausal symptoms and even in treatment of hormon-dependent tumours. The elicitor ethephon in concentration of 7000 µM, 700 µM and 70 µM was used in this work. The effect of ethephon inhibitor (AgNO3) in concentration of 120 µM was investigated too. Samples were examined after 24, 48, 72, 96 and 168 hours and then analysed by HPLC method. An effect of ethephon and its combination with AgNO3 was observed in callus and suspension cultures. Release of isoflavonoides into culture media was studied too. Daidzein production was the highest of all isoflavonoids in the callus culture after the treatment of ethephon in concentration of 700 µM after 96 hours (45,10 mg/g DW). The most...

The study is aimed to enhance in vitro production of secondary metabolites in Genista tinctoria L. via elicitor treatment. The different levels of elicitor concentration - selenium dioxide were utilized to affect the quantity of isoflavonoids occurred in cultures. Experiment was perfomed in callus and suspension cultures on MS nutrient media supplemented with 10 g l-1 of NAA (α-naphtylacetic acid) as growth regulator. The elicitor was added in the form of solution in concentrations of 9,012.10-3 mol l-1 ; 9,012.10-4 mol l-1 and 9,012.10-5 mol l-1 . It was exposed for 6, 12, 24, 48, 72 and 168 hours. The content of isoflavonoids was determined by HPLC in dry weight (DW) and medium. The most effective production of genistin (6,20 mg. g-1 DW, 8,30 mg. g-1 DW) in callus culture was measured. It was reached in concentrations of 9,012.10-4 mol l-1 and 9,012.10-5 mol l-1 after 168 h elicitor treatment. The second most satisfactory genistin level 5,20 mg g-1 DW was detected after elicitor application in concentration of 9,012.10-4 mol l-1 after 6 h. The content of genistein, daidzein and formononetin in callus culture was low and in the most cases equal zero compared to control samples. The content of biochanin A was equal zero compared to control samples. The most efficient daidzein production (37,10 mg...