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Considerable research has been concentrated on the foliage application of Cycoce, whereas little attention has focused on its use in seed application. Imbibition of caryopses of wheat (Triticum aestivum L.) in (2-chloroethyl) trimethylammonium chloride (Cycocel/CCC) resulted in a reduction in germination rate and a stunting of seedling growth. This was consistent with the appearance of a thicker stem, with shorter leaves than the control. Chlorophyll content per unit weight of leaf and numbers of tillers initiated both increased in comparison to controls. However, Cycocel treatment was accompanied by an enhanced survival capacity of seedlings when they were subjected to water limitation under growth room conditions. Seedlings grown from caryopses imbibed in 0.4 % Cycocel and exposed to a 7-day cycle of watering remained green and turgid beyond the time when the controls had wilted and died. Seedlings, at the fourth leaf stage, showed no wilting 23 days after watering had been withheld totally. Enhanced survival was also noted in seedlings when caryopses had been imbibed in Cycocel for 24 hours followed by a period of dry storage for up to 2 weeks prior to sowing. Enhanced survival was also detected as a carryover into the tillers, and the subsequent GEN2 seedlings, derived from GEN1plants. Cycocel pre-treatment did not alter Stomatal Index to an extent which could lead to enhanced water use efficiency, nor to the accumulation of proline to bring compatible solutes into equilibrium. However, the pre-treatment with Cycocel was found to enhance growth as a counter to water stress, and maintained fresh and dry weight of shoots when examined under the polyethylene glycol (PEG) induced stress. At the anatomical level the microscopic investigation of the GEN2 leaf tissues, derived from GENl plant, revealed a fully turgid cell structure, cells did not collapse and tissues were not distorted after the extraction of chlorophyll when compared with the control of the continuous watering as well as the moderate watering regime. Additionally, the cortex of GENl plants derived from pre-treated caryopses, showed a bright fluorescing unidentified deposition under Nutrient Solution (NS). This was more much greater when sampled from the NS + PEG treatments. From the results achieved Cycocel pre-treatment of caryopses appeared to have potential in manipulating wheat plants against water limitation. However, the mechanism (s) by which this can be achieved was not fully resolved in this study. Further investigations are required at the biochemistry and molecular level, particularly in relation to potential carryover effects between generations.

This dissertation examined the participation of eight lower-achieving readers in two intermediate-level elementary classrooms (one fourth- and one fifth-grade) during group discussions about literary texts. The purpose of the investigation was to determine the extent to which lower-achieving readers (defined as students who had persistent struggles to attain minimum scores on state, district, and classroom assessments in reading) displayed discourse features that indicated the students' high-level thinking during heterogeneous and homogeneous (by reading level) discussions about literary texts. Several characteristics of discourse indicate high-level thinking, including but not limited to: generalizations, analyses, speculations, affective responses, inter-textual connections, and elaborated explanations. A secondary purpose was to describe what happened when lower-achieving readers, their peers, and teachers engaged in group discussions about text. / A multiple case study design was used in this investigation. Data were collected between October 2005 and May 2006. Data sources included: field notes collected from participant observation, transcripts and indices of student and teacher interviews, transcripts and indices of audiotaped and videotaped discussions and reading lessons, and students' writing assignments and other artifacts. Multiple strategies were used to analyze the data, including analytic induction and descriptive statistical techniques. A discourse analysis coding scheme was used to determine the extent to which lower-achieving readers likely used high-level thinking about literary texts during group discussions. / The findings revealed focal students used the discourse of discussion as a tool to comprehend text in two ways. The students used the discourse about texts as intellectual scaffolds for their own thinking and transformation in understanding of the texts. In addition, the discussions created authentic opportunities for students to explore reading comprehension strategies (e.g., meanings of new words, visualizing the story). This means students drew on their knowledge of comprehension strategies and incorporated them into their discussions to reason about the texts without explicit instruction from the teacher. Focal students both evoked and heard others refer to and talk about the comprehension strategies during discussions. Moreover, an important contextual foundation of the discussions that seemed to relate to the focal students' thoughtful responses, or those that suggested the students went beyond recalling the literal details of the stories, was the use of the discourse to problem-solve about the meaning of the texts. Finally, in respect to the students' writing assignments that often followed the discussions about the texts, lower-achieving readers made use of the ideas of the discussions in their writing. / Regarding high-level thinking during discussions, the lower-achieving readers' discourse suggested that they thought in high-level ways about texts during discussions, and that they thought in high-level ways to the same extent or nearly the same extent as their peers did in the same discussions about texts. The one major difference in their talk about texts related to the instances of elaborated explanations or instances when students stated a position and explained their thoughts about the position with more than one reason or with evidence from the text. Higher-achieving readers produced significantly more 'elaborated explanations' during discussions than the lower-achieving readers in this study. / From a theoretical perspective, this investigation extends our understanding of lower-achieving readers' use of discursive practices that influence thinking and reasoning about text. From pedagogical perspectives, the findings suggest teachers might need to understand ways to encourage a kind of discourse that elicits genuine problem-solving about the meanings of text. Likewise, teachers might need to understand the discourse features that indicate high-level thinking to model and discuss the features in their work with lower-achieving readers during discussions about literary texts.

Graduation date: 1986

Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.

Thesis(M.S.)--Auburn University, 2006. / Abstract. Includes bibliographic references.

Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.

Thesis (Ph.D.) - James Cook University, 2002. / Typescript (photocopy) Bibliography: leaves 271-298.