Thesis (MScAgric)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.

Em função da elevada relação C/N da palhada da cultura do milho, esta mobiliza uma maior quantidade de nitrogênio para a sua decomposição. Este é um problema quando se cultiva em sucessão uma cultura também exigente em adubação nitrogenada, tal qual a cultura do trigo. Algumas espécies vegetais tais como o nabo forrageiro, a ervilhaca comum, o tremoço, o feijoeiro comum e a ervilha forrageira podem ser utilizadas como culturas intercalares no período outonal, entre a colheita do milho e a semeadura do trigo. Neste sentido, este trabalho teve como objetivo avaliar o efeito do cultivo do nabo forrageiro, da ervilhaca comum, do tremoço, da ervilha forrageira e do feijoeiro comum, utilizados como culturas intercalares entre a colheita do milho e a semeadura do trigo, comparados com o pousio, sobre o rendimento de grãos da cultura do trigo, cultivada com diferentes doses de adubação nitrogenada. O experimento foi conduzido em duas safras agrícolas (2009 e 2010) no município de Pato Branco-PR, instalado em sistema de semeadura direta, em delineamento experimental de blocos ao acaso com três repetições, num esquema fatorial, com a seguinte combinação de fatores: a) espécies intercalares; b) doses de nitrogênio (0, 40, 80 e 120 kg ha-1), aplicadas sobre a cultura do trigo. No momento em que as espécies nabo forrageiro, ervilhaca, tremoço e ervilha forrageira estavam para serem manejadas, foi feita a determinação de matéria seca. As amostras utilizadas para a determinação de matéria seca foram moídas e submetidas à análise para determinações das concentrações de carbono orgânico, nitrogênio total, fósforo, potássio, cálcio e magnésio. Após a determinação da matéria seca, foi avaliada a velocidade de decomposição da matéria seca e liberação de nutrientes da palhada do milho, nabo forrageiro, ervilha forrageira, tremoço, ervilhaca e feijão através da coleta de Litter bags. O rendimento de grãos de trigo em kg ha-1 foi obtido através da colheita das 8 linhas centrais das subparcelas, ajustado a 13% de umidade. Os cultivos da ervilha forrageira, do tremoço e do nabo forrageiro proporcionaram as maiores produções de matéria seca entre as espécies de cobertura. A relação C/N da palhada de milho e do feijoeiro comum não permitiu manter um equilíbrio adequado entre a mineralização e a imobilização do nitrogênio, diferentemente das demais espécies onde a mineralização foi superior a imobilização. Os maiores acúmulos de nitrogênio foram observados para a ervilha forrageira, tremoço e ervilhaca comum, enquanto o feijoeiro comum foi o tratamento que proporcionou os menores acúmulos de fósforo. O nabo forrageiro e o tremoço acumularam as maiores quantidades de potássio e cálcio e, juntamente com a ervilha forrageira, os maiores acúmulos de magnésio. O cultivo do trigo em sucessão a ervilha forrageira, nabo forrageiro e ervilhaca comum sem adubação nitrogenada proporcionou rendimentos equivalentes ao cultivo em sucessão a palhada de milho com no mínimo 40 kg ha-1 de N, em função do sincronismo da liberação de nitrogênio com as fases do trigo em que o nitrogênio é requerido em maiores quantidades. A ervilha forrageira e o nabo forrageiro, devido à elevada produção de matéria seca e liberação gradativa de nitrogênio, são alternativas promissoras para cultivo em sucessão ao milho e antecedendo a cultura do trigo. / High corn C/N straw ratio mobilizes a large amount of nitrogen for its decomposition being this a problem to the wheat cultivated in sequence once this crop also demand a significative nitrogen availability. Some plant species such as radish, common vetch, lupine, common bean and pea may be used as an alternative of catch crops at autumn, between corn harvest and wheat sowing. In this way, this study aimed to evaluate the effect of cultivation of radish, common vetch, lupine, pea, and the common bean, used as catch crops between corn harvest and wheat sowing, compared with fallow over the grain yield of wheat, grown under different nitrogen fertilization levels. Experiment was carried out along 2009 and 2010 growing season at Pato Branco-PR on a no-tillage system management and laid out as randomized blocks with three replications with a factorial scheme: a) cover crops; b) nitrogen levels (0, 40, 80 e 120 kg ha-1). Dry matter determination was done at the time that the species turnip, vetch, lupine and pea were able to be managed. Dry matter samples were ground and subjected to chemical analysis to determinate the concentrations of organic carbon, total nitrogen, phosphorus, potassium, calcium and magnesium. After determining the dry matter was measured the decomposition rate of dry matter and nutrient release from corn straw, turnip, pea, lupine, vetch and beans through the Litter bags technique. Wheat grain yield in kg ha-1 was obtained by harvesting eight central rows of the subplots, adjusted to 13% of moisture. Forage pea, lupine and wild radish were the most productive crops among the cover crop species. Corn straw and common bean C/N ratio did not maintain a proper balance between nitrogen mineralization and immobilization, unlike other species where mineralization was higher than immobilization. The highest nitrogen accumulations were observed for forage pea, lupine and vetch, while the common bean was the treatment that showed the smallest accumulation of phosphorus. Radish and lupine accumulated the largest amounts of potassium and calcium and along with forage pea, the highest accumulation of magnesium. Wheat cultivation in succession to forage pea, turnip and common vetch without N fertilizer provided equivalent yields to the cultivation in succession to the corn straw with at least 40 kg of N ha-1, due to the synchronism between nitrogen releases from these species with the stage of wheat in which the nitrogen is required in greater quantities.

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Includes bibliographical references (leaves 143-165) Reports on studies undertaken to examine the physiological basis of the known ability of lupin grain to increase ovulation rate in the ewe.

[Truncated abstract] Narrow-leaf lupin (Lupinus angustifolius L.) was first recorded as having been introduced into Germany during the mid-19th century for use as green manuring and as fodder crops. However, it was not until post World-War I that there was any serious attempt to domesticate the species. Since that time several key domestication genes have been incorporated to enable the species to be grown as a crop over a range of climates, harvested as a bulk commodity and, the seed used for both animal and human consumption. However, the recent domestication of this species has seen a rather limited use of wild germplasm largely as a result of the difficulty in retaining these key domestication genes. To make the task of retaining these genes manageable, it was decided to resort to molecular technology. A mapping population of F8 derived recombinant inbred lines (RILs) has previously been established by the Department of Agriculture and Food, Western Australia, from a cross between a domesticated breeding line 83A:476 and a wild type P27255 in narrow-leaf lupin. The parents together with 89 RILs (of a population of 115) were subjected to DNA fingerprinting using microsatelliteanchored fragment length polymorphism (MFLP) to rapidly generate DNA markers for construction of a linkage map. Five hundred and twenty two unique markers of which 21% were co-dominant, were generated and mapped. Phenotypic data for the domestication traits: mollis (soft seeds), leucospermus (white flower and seed colour); Lentus (reduced pod-shattering), iucundis (low alkaloid), Ku (early flowering) and moustache pattern on seed coats; were included. Three to 7 molecular markers were identified within 5 cM of each of these domestication genes. The anthracnose resistance gene Lanr1 was also mapped. Linkage groups were constructed using MapManager version QTXb20, resulting in 21 linkage groups consisting of 8 or more markers. ... Five pairs of QTLs were found to be involved in epistasis, 2 of these having an effect on early vigour and another 3 influencing the time to opening of the first florets. Variation explained for each trait ranged from 28% for seed size, to 88% for days to flowering. We showed that it was possible to use this data to predict genotypes of superior progeny for these traits under Mediterranean conditions. QTL regions were compared on a second published linkage map and regions of conserved synteny with the model legume Medicago truncatula high-lighted. The work presented in this thesis demonstrates the importance of tight linkage between markers and genes of interest. It is especially important when dealing with genetically diverse material as found in the wild. One of the main problems faced by molecular scientists is the phenomenon known as linkage disequilibrium in marker populations caused by either small population size or 4 insufficient opportunity for recombination. This frequently results in the development of markers with little or no application outside of the population in which it was developed. Although the relatively small size of the population used in this study exposes it to such constraints, in this case excellent and valuable results were achieved in developing useful markers to at least 3 of the domestication traits within a relatively short time period of less then 4 years.

Includes bibliographical references (leaves 143-165) / xiii, 168 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Reports on studies undertaken to examine the physiological basis of the known ability of lupin grain to increase ovulation rate in the ewe. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Sciences, Waite Agricultural Research Institute, 1989

Thesis (MSc)--Stellenbosch University, 1955. / ENGLISH ABSTRACT: no abstract available / AFRIKAANSE OPSOMMING: geen opsomming

Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2005. / The demand for protein for human and animal nutrition in South Africa is increasing and it will continuously increase. The effect of replacing soybean oilcake meal as protein source for broilers and full-fat soybean meal for weaner pigs, with different levels of sweet lupins (Lupinus angustifolius), canola oilcake and full-fat canola was examined. A basal diet with soybean oilcake as protein source was mixed with a diet using either sweet lupins or canola oilcake or full-fat canola in ratios of 100%, 67% and 33% respectively. In the broiler trial the test diets were fed for a period of six weeks with or without the enzyme Vegpro (Alltech). Pigs were fed the test diets, with and without Roxazyme® enzyme, ad libitum from 8.5 to 25 kg live weight. The fatty acid content of the fat pads of the broilers raised on the different diets was determined. The pigs were kept in the trial up to the grower- finisher phase. The fatty acid content of the carcass fat and muscle of pigs raised on the different diets was determined. The inclusion of enzymes had no effect on the growth, feed intake or feed conversion ratio of broilers fed the test diets. The provision of external dietary enzymes to the weaner pig diets failed to improve either dry matter intake or growth rate, but improved the feed conversion ratio. Broiler weights at six weeks of age were significantly higher for the control diet compared to the 20% lupin diet. There was no significant difference in the feed intake as the lupin content of the diets increased. The feed conversion ratio did not differ significantly between the control diet and the 6.6% lupin diet but became significantly poorer as the lupin content increased to 13.2% and 20% of the test diet. There were no significant differences in production performance of the control diet and the canola oilcake containing diet. The broiler weights at six weeks decreased significantly with each increase in the canola oilcake content of the diets. The feed intake of the 20% canola oilcake diet at week six was significantly less than the intake of the control diet, but not significantly less than the 6.6% and 13.2% canola oilcake diets. The feed conversion ratio of the control diet was significantly better than the 13.2% and 20% canola oilcake diets. No significant differences were found in week six between the 6.6% full-fat canola diet and the control diet for broiler weights and feed intake. The feed conversion ratio of the broilers fed the 13.2% and 20% full-fat canola diets was significantly poorer than the control diet. The final body weights of the weaner piglets fed the control diet were significantly higher than the final body weights of weaner piglets fed the lupin containing diets. The average daily gain of the weaner piglets fed the control diet was significantly higher than the gain of the weaner piglets fed the lupin containing diets. No significant differences in the feed intake and feed conversion ratio between the different lupin inclusion levels were detected. There were no significant differences in body weight, feed intake, average daily gain and the feed conversion ratio, between the various full-fat canola containing diets and the control diet. A significant difference in body weight was found between the weaner piglets fed the 20% canola oilcake diet and the weaner piglets fed the control diet. There were no significant differences in feed intake between the various inclusion levels of canola oilcake. The control and 6.6% canola oilcake containing diets had significantly higher average daily gains than the 20% canola oilcake containing diet. In the final trial the finisher pigs fed the test diet containing 25.00% lupins, had a final body weight significantly lighter than the final body weight of the finisher pigs fed the other test diets. The finisher pigs fed the test diet containing 25.00% lupins, also had a significantly reduced average daily gain and feed intake. The feed intake of the 25.00% canola oilcake diet was significantly lees than the feed intake of the 16.75% full-fat canola containing diet. The feed conversion ratio of the 25.00% lupin containing diet was significantly poorer than the feed conversion ratio of the 16.75% lupin containing diet, 8.25% lupin containing diet, 16.75% full-fat canola containing diet, 25.00% canola oilcake containing diet and the control diet. In a choice feeding trial growing pigs were offered four diets with four different protein sources: sweet lupins (25% inclusion level), canola oilcake (25% inclusion level), full-fat canola (25% inclusion level) and soybean oilcake (25% inclusion level), while their daily intakes were recorded. In a second choice feeding trial pigs were offered ten different diets with increasing levels (6.6%, 13.2%, 20%) of either sweet lupins, canola oilcake meal or full-fat canola meal. The pigs consumed significantly more of the soybean oilcake containing diet compared to diets containing the alternative protein sources. Pigs consumed significantly less of the full-fat canola diet compared to the sweet lupin and canola oilcake diets. Ten different canola cultivars were collected from two different locations in the Mediterranean rainfall area of South Africa namely the Western Cape (Swartland) and Southern Cape (Rûens) grain producing areas. The sinapine and glucosinolate content of various canola cultivars was compared and the influence of locality on the sinapine and glucosinolate content of the canola cultivars was determined. There were no significant differences (P < 0.05) in sinapine content when the canola produced in the Western and Southern Cape were compared. Varola 54 and Rainbow cultivars had significantly higher (P < 0.05) sinapine contents compared to the Varola 50 cultivar. Samples of lupins, field peas, faba beans and narbon beans were collected and analysed for amino acids, alkaloids, non-starch polysaccharides, tannin and starch. The digestible energy value of these alternative protein sources for pigs was determined. Significant differences were found in the amino acid content of the various crops. The alkaloid content of the lupins varied significantly between the sweet and bitter lupin varieties. Sweet L. angustifolius cultivars contained ca 50mg/kg and the bitter L. angustifolius cultivars ca 15000mg/kg alkaloids. The mean alkaloid content of L. albus cultivars was ca 1300mg/kg. The faba beans, narbon beans and peas had significantly higher values for tannins and starch, compared to lupins.