Bibliography: leaves 203-220. / xii, 220 leaves : ill., map ; 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 Crop Protection, 1993

Bibliography: leaves 203-220.

Bibliography : leaves 159-184. This study found at least three mechanisms of resistance to the acetyl coenzyme A carboxylase (ACCase)-inhibiting herbicides. A modified target -site was responsible for moderate and high resistance to herbicides at the whole plant level. Enhanced herbicide metabolism and reduced translocation of herbicide to the target site was observed in one resistant biotype each.

Bibliography: leaves 128-146. Study was undertaken to determine the occurence and species incidence of wild oats in a major cropping region of southern Australia. Population dynamic studies were undertaken at two sites to define the seed bank decline and emergence pattern of several wild oat populations over a three year period. Management studies were conducted to determine appropriate strategies for the control of wild oats in southern Australian farming systems.

Obesity, glucose intolerance or insulin resistance and elevated blood pressure are now prevalent in the U.S. Increased intake of dietary fiber, omega- 3 fatty acids, and antioxidants may help prevent or manage these diseases. Tortillas are now part of the American diet, and are excellent carriers of higher amounts of fiber and other nutraceutical ingredients. This study was conducted to determine the effects of incorporating nutraceutical ingredients (flaxseed, sorghum bran, oat flour, buckwheat flour) on whole white wheat tortilla quality. Tortillas were prepared using a hot-press, gas-fired oven and were evaluated for physical properties, texture and shelf-stability. Objective and subjective tests demonstrated that whole white wheat and multigrain tortilla doughs were harder, rougher and less extensible than refined flour tortilla dough. Multigrain flour tortillas were thinner, larger and more translucent than the refined flour treatment. Incorporation of whole multigrain flours affected color of the product, giving darker tortillas. Tortilla flexibility decreased over time. After 16 days of storage rollability scores of tortillas decreased drastically. The most pronounced decrease in tortilla flexibility was observed for 5% sorghum bran, 10% buckwheat, and for the treatment prepared with of 5% flax, 5% sorghum, 5% oat, 5% buckwheat. The flexibility loss was higher for whole white wheat and multigrain tortillas than for the refined one which was confirmed with objective and subjective tests. To extend shelf stability of whole multigrain tortillas various amounts of commercial hydrocolloid and ?-amylase were added to the formulation. Tortillas with 75 ppm, 100 ppm of ?-amylase, 1% and 1.5% of gum retained their flexibility during 16 days of storage. Consumer acceptability of the whole multigrain tortillas (5% flaxseed, 5% sorghum bran, 5% oat, 5% buckwheat) was compared with commercial multigrain tortillas and whole white wheat flour tortillas using an untrained sensory panel. The multigrain tortillas were liked by the panel as much as the other samples. Prepared multigrain tortillas had improved nutritional value. Each multigrain treatment contained at least 3 g of dietary fiber, 0.29 g of ?- linolenic fatty acid, lignans and antioxidants. It makes possible to claim them as a ?good source of dietary fiber? and ?an excellent source of ?-linolenic fatty acid?. The formulations tested, together with future refinements, provide more options to consumers seeking healthier alternatives to refined wheat flour tortillas.

<p>As the interest in biological sequence analysis increases, more efficient techniques to sequence, map and analyse genome data are needed. One frequently used technique is EST sequencing, which has proven to be a fast and cheap method to extract genome data. An EST sequencing generates large numbers of low-quality sequences which have to be managed and analysed further.</p><p>Performing complete searches and finding guaranteed results are very time consuming. This dissertation project presents a method that can be used to perform rapid gene prediction of function-specific genes in EST data, as well as the results and an estimation of the accuracy of the method.</p><p>This dissertation project applies various methods and techniques on actual data, attempting to identify genes involved in cold-associative processes in plants. The presented method consists of three steps. First, a database with genes known to have cold-associated properties is assembled. These genes are extracted from other, already sequenced and analysed organisms. Secondly, this database is used to identify homologues in an unanalysed EST dataset, generating a candidate-list of cold-associated genes. Last, each of the identified candidate cold-associative genes are verified, both to estimate the accuracy of the rapid gene prediction and also to support the removal of candidates which are not cold-associative.</p><p>The method was applied to a previously unanalysed Avena sativa EST dataset, and was able to identify 135 candidate genes from approximately 9500 EST's. Out of these, 103 were verified as cold-associated genes.</p>

As more contaminated sites are being discovered, new in situ remediation techniques need to be developed. Chemically treating soil with lime to increase soil pH is a method that may decrease the bioavailability of the contaminant. To test the usefulness of rendering metal-contaminated soils alkaline with dolomitic lime, to improve crop performance, field trials at a site in Port Colborne, ON, with soil nickel concentration (as high as 5000 mg/kg) from refinery emissions were completed. Oat and soybean yield, as well as plant uptake and bioavailabilty of nickel in soil were evaluated. Liming Ni-contaminated soils decreased soybean foliar Ni concentrations from 36.68 µg/g in unlimed fields to 19.98 µg/g in 50 t/ha limed fields in the 2007 growing season; yield of both oat and soybean in unlimed soils was the same (p>0.05) as at a reference site, suggesting that for these soils, remediation is not necessary for yield.

The objective of this research was to determine the effect of stage of maturity at the time of harvest for barley and oat whole-crop forage on feed intake, ruminal fermentation and digestibility, and the impact forage allocation has on intake and ruminal fermentation. In the first 2 studies, whole-crop barley (Study 1; c.v. CDC Cowboy) and oat (Study 2; c.v. CDC Weaver) forage were harvested at the late milk (LM), hard dough (HD) and ripe (RP) stages and offered ad libitum to ruminally cannulated heifers. Diets were supplemented in an attempt to balance crude protein (CP) among treatments. Heifer performance, dry matter intake (DMI), ruminal fermentation parameters, ruminal digestibility, and total tract digestibility were evaluated. In Study 3, whole-crop oat (c.v. CDC Weaver) forage harvested at HD and RP was offered ad libitum to ruminally cannulated heifers in either daily (1-D) or 3 d (3-D) allocations. Dry matter intake and ruminal fermentation parameters were measured. In Study 1, harvest maturity of barley did not affect DMI (P = 0.70; average 5.4 kg/d) or average daily gain (ADG; P = 0.64). Total tract digestibility was decreased for barley harvested at HD (P = 0.003), but harvest maturity did not affect daily digestible energy (DE) intake (P = 0.52). Minimum ruminal pH for heifers fed the barley forage was lowest for LM (6.09), intermediate for RP (6.13), and greatest for HD (6.25; P = 0.016). Total short chain fatty acid (SCFA) concentrations were not affected by harvest maturity (P = 0.36). In Study 2, harvest maturity of whole-crop oat did not affect DMI (P = 0.26; average 8.1 kg/d) or ADG (P = 0.52). There were no effects of harvest maturity of oat forage on total tract digestibility (P = 0.78) or daily DE intake (P = 0.68). The minimum ruminal pH from heifers fed oat forage was lowest for HD (5.84; P = 0.012), intermediate for RP (5.94) and greatest for LM (5.99). There was no effect of harvest maturity of oat forage on total SCFA concentrations (P = 0.21). The quantity of forage allocation (Study 3) had no effect on total or forage DMI over a 3-d duration (P ≥ 0.47). Throughout the 3-d feeding period, 3-D allocated heifers had a reduction in the area pH was under 5.8 (214.4, 79.5 and 10.9 pH × min/d, for d 1, 2 and 3, respectively; P = 0.003). Total SCFA concentrations were not affected by forage allocation or harvest maturity (P ≥ 0.14), however there was an interaction of forage allocation and day in the feeding cycle (P = 0.046). Heifers allocated 1-D had no change iii in total SCFA concentration over the 3-d feeding period (averaged 122 mM), but 3-D allocation had elevated concentrations on d 1 (138 mM) intermediate on d 2 (135 mM) and decreased on d 3 (117 mM). These data suggest that harvesting barley and oat at the HD stage improves DM yield without negatively affecting cattle DMI and ADG. These data also suggest that providing 3-d allocations of forage does not affect DMI, but can increase daily fluctuations of ruminal pH and ruminal SCFA concentrations.

Bibliography : leaves 159-184. / xv, 191 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This study found at least three mechanisms of resistance to the acetyl coenzyme A carboxylase (ACCase)-inhibiting herbicides. A modified target -site was responsible for moderate and high resistance to herbicides at the whole plant level. Enhanced herbicide metabolism and reduced translocation of herbicide to the target site was observed in one resistant biotype each. / Thesis (Ph.D.)--University of Adelaide, Dept. of Crop Protection, 1996

Thesis (Ph.D.) - University of Queensland, 2003. / Includes bibliography.