Thesis (MTech (Agriculture))--Cape Peninsula University of Technology, 2018. / Zinc deficiency on various soil types have been reported in arable soils of sub Saharan Africa (SSA) including South Africa. A pot trial was conducted at the Cape Peninsula University of Technology, Wellington campus to investigate the interaction of different application rates of Zn at various soil pH on the grain yield and quality of spring wheat in a completely randomized factorial design replicated three times. The four soil pH tested were: pHA: 5.1, pHB: 5.6, pHC: 6.1, pHD: 6.6 which correspond to lime application at 0, 0.5, 1 and 1.5 t/ha. Five Zn rates (Zn1: 3.5; Zn2: 4.5; Zn3: 5.5 Zn4: 6.5, and Zn5: 7.5 mg /kg soil which correspond to Zn1: 7; Zn2: 9; Zn3: 11; Zn4: 13 and Zn5: 15 kg /ha) were applied at two (planting and flowering) growth stages. Yield and yield component data collected were analyzed using SAS version 9.2 and means were separated by Duncun’s Multiple Range Test (DMRT). The results showed that grain yield and yield components were significantly affected by lime application pHC (6.1): 1t/ha at planting. Zn application at planting had no significant effect on the grain yield and yield components. However, at flowering, the simultaneous increase of Zn along with increase in lime positively affected grain yield and yield components. Plant analysis showed that at both stages (planting and flowering), Zn application, especially at pH 6.6, significantly increased P, K, Ca, Na, Mg Fe, Cu and B concentrations in wheat grain, but the concentrations of N, Mn, Zn and protein remained unaffected. Zn application had no effect on most nutrients due to the presence of lime. While the absence of lime, Zn4: 6.5mg/kg (corresponding to 13kg/ha) significantly increased the nutrients. In addition, Zn3: 5.5mg/kg (corresponding to 11kg/ha) promoted Zn absorption by grain in all treatments.

Com o objetivo de avaliar as características produtivas e a severidade de doenças de linhagens avançadas de aveia branca, provenientes de cruzamentos controlados do programa de melhoramento de aveia da APTA, visando à seleção de materiais com qualidades agronômicas superiores para o Estado de São Paulo, foram realizados experimentos no Pólo Regional de Desenvolvimento Tecnológico dos Agronegócios do Sudoeste Paulista, em Capão Bonito, nas safras de inverno de 2004 a 2007. Foram avaliados vinte genótipos (IAC-7, CB990107, CB990318, CB990321, CB990324, CB990434, CB990436, CB9952115, CB9958126, CB9958128, CB9960132, CB9962152, CB9968160, CB9968162, CB9968165, CB9968167, CB9924172, CB9930177, CB9967184 e CB9967185) de aveia branca (Avena sativa L.) em relação ao estande, altura de plantas, produtividade e severidade de doenças. O delineamento experimental foi o de blocos ao acaso, com vinte tratamentos e três repetições. Cada parcela experimental foi constituída por quatro linhas de três metros de comprimento, espaçadas de 0,20m, sendo consideradas como área útil, para realização das avaliações, as duas linhas centrais. Houve diferenças significativas entre os genótipos em relação a todos os caracteres avaliados, exceto para helmintosporiose em 2004, 2006 e 2007. Os resultados permitiram obter as seguintes conclusões: (i) as linhagens CB9967184, CB9962152, CB990436, CB9960132, CB990321, CB990434, CB990324, CB9930177, CB9967185, CB990107 e CB9968165 possuem características produtivas promissoras, e (ii) as linhagens CB990318, CB9967185, CB9968167, CB9967184, CB9924172 e CB9960132 possuem nível promissor de resistência/tolerância à ferrugem da folha, helmintosporiose e virose do nanismo amarelo da cevada. Essas linhagens devem ser mais bem avaliadas para seu futuro lançamento como novas variedades de aveia branca para o cultivo no Estado de São Paulo. / With the purpose of evaluating the productive characters and the diseases severity of white oat genotypes, from controlled crosses of APTA oat breeding program, seeking the selection of materials with superior agronomic qualities to the State of São Paulo, field experiments were carried out at \'Technological Development Regional Center of Agribusiness\' of the Southwest region of São Paulo State, in Capão Bonito county, during the winter seasons from 2004 to 2007. Twenty white oat (Avena sativa L.) genotypes were evaluated (IAC-7, CB990107, CB990318, CB990321, CB990324, CB990434, CB990436, CB9952115, CB9958126, CB9958128, CB9960132, CB9962152, CB9968160, CB9968162, CB9968165, CB9968167, CB9924172, CB9930177, CB9967184 and CB9967185) in relation to stand, plant height, productivity and disease severity. The statistical experimental design was random blocks, with twenty treatments and three replications. Each experimental plot had four rows of three meters length (spacing of 20cm between plant rows), being considered as useful area, to make the evaluations, the two central rows. There were significant differences among genotypes for all characters evaluated, except for helminthosporium disease in 2004, 2006 and 2007. The results allowed to obtain the following conclusions: (i) the genotypes CB9967184, CB9962152, CB990436, CB9960132, CB990321, CB990434, CB990324, CB9930177, CB9967185 and CB990107 have promising productive characters, and (ii) the genotypes CB990318, CB9967185, CB9968167, CB9967184, CB9924172, CB9960132 and CB9968165 have promising level of resistance/tolerance to leaf rust and helminthosporium diseases and viral disease of barley yellow stunting. These genotypes should be better evaluated to their future release as new white oat varieties to be cultivated at State of São Paulo.

Com o objetivo de avaliar as características produtivas e a severidade de doenças de linhagens avançadas de aveia branca, provenientes de cruzamentos controlados do programa de melhoramento de aveia da APTA, visando à seleção de materiais com qualidades agronômicas superiores para o Estado de São Paulo, foram realizados experimentos no Pólo Regional de Desenvolvimento Tecnológico dos Agronegócios do Sudoeste Paulista, em Capão Bonito, nas safras de inverno de 2004 a 2007. Foram avaliados vinte genótipos (IAC-7, CB990107, CB990318, CB990321, CB990324, CB990434, CB990436, CB9952115, CB9958126, CB9958128, CB9960132, CB9962152, CB9968160, CB9968162, CB9968165, CB9968167, CB9924172, CB9930177, CB9967184 e CB9967185) de aveia branca (Avena sativa L.) em relação ao estande, altura de plantas, produtividade e severidade de doenças. O delineamento experimental foi o de blocos ao acaso, com vinte tratamentos e três repetições. Cada parcela experimental foi constituída por quatro linhas de três metros de comprimento, espaçadas de 0,20m, sendo consideradas como área útil, para realização das avaliações, as duas linhas centrais. Houve diferenças significativas entre os genótipos em relação a todos os caracteres avaliados, exceto para helmintosporiose em 2004, 2006 e 2007. Os resultados permitiram obter as seguintes conclusões: (i) as linhagens CB9967184, CB9962152, CB990436, CB9960132, CB990321, CB990434, CB990324, CB9930177, CB9967185, CB990107 e CB9968165 possuem características produtivas promissoras, e (ii) as linhagens CB990318, CB9967185, CB9968167, CB9967184, CB9924172 e CB9960132 possuem nível promissor de resistência/tolerância à ferrugem da folha, helmintosporiose e virose do nanismo amarelo da cevada. Essas linhagens devem ser mais bem avaliadas para seu futuro lançamento como novas variedades de aveia branca para o cultivo no Estado de São Paulo. / With the purpose of evaluating the productive characters and the diseases severity of white oat genotypes, from controlled crosses of APTA oat breeding program, seeking the selection of materials with superior agronomic qualities to the State of São Paulo, field experiments were carried out at \'Technological Development Regional Center of Agribusiness\' of the Southwest region of São Paulo State, in Capão Bonito county, during the winter seasons from 2004 to 2007. Twenty white oat (Avena sativa L.) genotypes were evaluated (IAC-7, CB990107, CB990318, CB990321, CB990324, CB990434, CB990436, CB9952115, CB9958126, CB9958128, CB9960132, CB9962152, CB9968160, CB9968162, CB9968165, CB9968167, CB9924172, CB9930177, CB9967184 and CB9967185) in relation to stand, plant height, productivity and disease severity. The statistical experimental design was random blocks, with twenty treatments and three replications. Each experimental plot had four rows of three meters length (spacing of 20cm between plant rows), being considered as useful area, to make the evaluations, the two central rows. There were significant differences among genotypes for all characters evaluated, except for helminthosporium disease in 2004, 2006 and 2007. The results allowed to obtain the following conclusions: (i) the genotypes CB9967184, CB9962152, CB990436, CB9960132, CB990321, CB990434, CB990324, CB9930177, CB9967185 and CB990107 have promising productive characters, and (ii) the genotypes CB990318, CB9967185, CB9968167, CB9967184, CB9924172, CB9960132 and CB9968165 have promising level of resistance/tolerance to leaf rust and helminthosporium diseases and viral disease of barley yellow stunting. These genotypes should be better evaluated to their future release as new white oat varieties to be cultivated at State of São Paulo.

Thesis (M.Sc. (Agriculture)) --University of Limpopo, 2018 / Tomato is second most cultivated crop globally and in South Africa it is planted by both commercial and smallholder farmers. However, the crop is susceptible to a number of diseases including those caused by fungal pathogens. Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici and seedling damping-off caused by Rhizoctonia solani, are known to cause serious yield loss in tomato production. Their management is mainly based on the application of synthetic fungicides and cultural practices. However, both methods have limitations which result in their inefficiency. Synthetic fungicides also have negative impact on the environment and human health. The ability of fungal pathogens to develop resistance to fungicides has also resulted in their reduced application. These challenges have led to a need to identify novel methods using plant extracts and biological control agents which can be used to manage these diseases. The objectives of this study were therefore to, firstly determine the efficacy of both plant extracts on mycelial growth of F. oxysporum f. sp. lycopersici and R. solani under laboratory conditions and secondly, to evaluate the effectiveness of both plant extracts as well as antagonistic fungi Trichoderma harzianum against Fusarium wilt and damping-off of tomato under greenhouse conditions. Food poisoning assay was used to investigate the efficacy of M. burkeana and M. oleifera extracts in vitro. Six (0, 2, 4, 6, 8, 10 g/ml) treatments were arranged in a completely randomised design and replicated four times. After 7 days of incubation at 25 °C, radial growth colony was measured. For the greenhouse xp im nt, Fusa ium wilt was t st d on cv. ‘HTX14’ as th most susc ptibl cultiva whilst seedling damping-off was t st d on cv. ‘Mon y-make ’. Aqu ous xt acts were prepared by decocting different concentrations of M. burkeana (4, 6, 8 g/ml) xiv and M. oleifera (2, 4 and 6 g/ml) in 100 ml of distilled water at 100 °C for 15 minutes then left to cool before filtering and applying as a treatment. Trichoderma harzianum as a treatment was applied 7 days after inoculating the soil-borne pathogens. In-vitro M. burkeana treatments concentrations had the highest mycelia growth suppression against both F. oxysporum f. sp. lycopersici at 10 g/ml (76 %) whilst suppression on R. solani was at 8 g/ml (71 %) relative to control. Moringa oleifera xt acts’ highest pathogen suppression for both F. oxysporum f. sp. lycopersici and R. solani were respectively 35 % and 60 % relative to control at concentration 6 g/ml. Under greenhouse conditions shoot disease severity had highest suppression at 0.6 g/ml of M. burkeana and 0.4 g/ml of M. oleifera treatment concentrations resulting to 32 and 49 % relative to control. Whereas, treatment 0.8 g/ml of M. burkeana and 0.4 g/ml of M. oleifera suppressed stem and root discoloration by 39 and 54 % respectively. Trichoderma harzianum significantly (P ≤ 0.05) reduced shoot severity and root and stem discolouration contributing the highest suppression of 49 % relative to control. In damping-off treatments, both plant extracts and T. harzianum also significantly duc d (P ≤ 0.05) pre- and post-emergence damping-off incidence with M.burkeana recording the highest suppression at 78 % followed by M. oleifera at 64 %. Trichoderma harzianum reduced incidence of damping-off by 60 % relative to untreated control on both M. burkeana and M. oleifera experiments. The results of this study showed that M. burkeana, M. oleifera extracts and T. harzianum can be highly suppressive to both tested plant diseases. However, further studies should be conducted to determine their mode of action, application method and their effect on other soil microorganisms. Keywords: Damping-off, Fusarium wilt, Plant extracts, T. harzianum, Tomato plant

Thesis (M.S.)--Mississippi State University. Department of Entomology and Plant Pathology. / Title from title screen. Includes bibliographical references.

Includes bibliographies. / xiv, 175, [96] leaves, [17] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis reports on the generation of molecular tools for the analysis of chromosome 6R of rye and the application of these tools in structural analysis of 6RL. Results presented include physical and genetic maps of chromosome 6RL incorporating RFLP and PCR markers and CreR, the locus conferring resistance to cereal cyst nematode (CCN). The ability to detect small introgessions of rye chromatin in wheat is demonstrated. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1997

Typescript / Includes bibliographical references / 134 leaves : ill. ; 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 Plant Pathology, 1966

Bibliography: leaves 133-152 / iv, 152 leaves, [47] leaves of plates : ill. (1 col.) ; 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, 1987

Thesis (M.Sc. (Biochemistry, Microbiology & Biotechnology)) - Rhodes University, 2008.

Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2008. / Full text also available online. Scroll down for electronic link.