Triacylglycerol (TAG) production in the microspore derived (MD) cell suspension culture ofBrassica napus L. cv Jet Neuf was enhanced when the sucrose concentration in the growth medium was increased from 2 to 14 % (w/v). mRNA differential display by polymerase chain reaction was used to examine gene expression in cells grown at different sucrose concentrations in order to identify mRNAs which could be associated with oil formation. The anchored primer, T12AA, was used to screen one subset, representing approximately one twelfth of the transcript population, isolated from cultures grown in media supplemented to 2, 6 and 14 % (w/v) sucrose. Analysis of this mRNA subset revealed thirteen cDNAs which appeared to be upregulated as the sucrose concentration was increased. Cloning and sequencing revealed multiple cDNA fragments for each signal detected by differential display. RT-PCR analysis of sixteen different cDNAs revealed that eight encoded mRNAs which were upregulated in parallel to the increase in media sucrose. Comparison of the eight upregulated cDNAs to other sequences in GenBank revealed the following: (1) BSS8A had a 100% identity with the last 25 amino acids of an acyl carrier protein from Arabidopsis thaliana, (2) BSS1A displayed homology to a number of sequences of unknown function, (3) BSS1 IB displayed weak but significant homology to a number of sequences of unknown function, (4) BSS13A displayed homology to four members of the thioredoxin family from ,4. thaliana and (5) four Had no significant homology to previously reported sequences which makes them potential candidates to encode lipogenic enzymes. These results indicate that differential display of mRNA may be a simple and rapid method for the identification of sucrose-modulated gene expression changes in this system and for the characterization of novel sequences potentially encoding lipogenic proteins. / xxi, 256 leaves : ill. ; 28 cm.

Graduation date: 1992

Thesis (Ph.D.)--Murdoch University, 2004. / Thesis submitted to the Division of Science and Engineering. Bibliography: leaves 160-193.

O crambe (Crambe abyssinica) apresenta elevado potencial para a produção de biodiesel e é uma alternativa para a segunda safra, cultura de outono/inverno e rotação de culturas. A cultura apresenta diversas características interessantes ao produtor, entre elas: alto teor de óleo na semente, baixo custo de produção, tolerância ao estresse hídrico, rusticidade e precocidade. O objetivo do trabalho foi definir para a região Sudoeste do Paraná o espaçamento e densidade de semeadura além da época de semeadura e seus efeitos sobre a qualidade das sementes, bem como determinar o consumo hídrico e o coeficiente de cultura. Foram realizados quatro experimentos, na Universidade Tecnológica Federal do Paraná – Campus Dois Vizinhos, nos anos de 2012 e 2013, buscando analisar os efeitos da época de semeadura, espaçamento e densidade de cultivo do crambe, o consumo hídrico da planta e análise fisiológica das sementes produzidas. As épocas de semeadura foram de 28 de março a 08 de junho sendo realizados a cada 15 dias. Os espaçamentos de 17 e 51 cm e densidades de 60, 80, 100, 120 e 140 sementes m-2. Foram avaliados os parâmetros produção, germinação, índice de velocidade de germinação, comprimento de plântulas e matéria seca das plântulas. A melhor época observada de semeadura foi a segunda semana de março. Não houve efeito significativo do espaçamento sob a produtividade. As densidades de 100 a 140 sementes m-2, apresentaram os melhores resultados. O Kc foi de 0,64 até o início de florescimento, 0,84 até início da frutificação e 0,79 até início da senescência. / The crambe (Crambe abyssinica) presents itself as a full potential for this end and also it’s a great alternative to the second harvest, the fall/winter´s culture and crop rotations. Crambe shows many good characteristics that are very interesting for the producer, among them are: high concentration of fat in the seed, low production cost, high tolerance to hydric stress, simplicity and precocity. The main objective was to define the spacing and density for the Southwest region of Paraná, and also determine the plantation period as well it´s effects over the quality of the seeds, furthermore the determination of the hydric consumption and culture rate. Four other experiments were conducted at Universidade Tecnológica Federal do Paraná – Campus Dois Vizinhos, in the years 2012 and 2013, seeking to analyze the effects in the plantation period, spacing, density, water consumption and the physiologic analysis of the produced seeds. The planting occurred between March 28th until June 8th each one being planted every 15 days. The spacing were from 17 and 51 cm. and densities of 60, 80, 100, 120 and 140 seeds per m². The analysis of the seed consists in: Germination, index of germination speed, length of the seedlings and dry matter of the seedlings. The best period for both of planting as quality of the production itself was in the second week of March, the spaces did not interfere and the best densities are 100 to 140 seeds per m². The Kc was 0,64 until the blossoming, 0,84 until the fructification and 0,79 until ripeness.

O crambe (Crambe abyssinica) apresenta elevado potencial para a produção de biodiesel e é uma alternativa para a segunda safra, cultura de outono/inverno e rotação de culturas. A cultura apresenta diversas características interessantes ao produtor, entre elas: alto teor de óleo na semente, baixo custo de produção, tolerância ao estresse hídrico, rusticidade e precocidade. O objetivo do trabalho foi definir para a região Sudoeste do Paraná o espaçamento e densidade de semeadura além da época de semeadura e seus efeitos sobre a qualidade das sementes, bem como determinar o consumo hídrico e o coeficiente de cultura. Foram realizados quatro experimentos, na Universidade Tecnológica Federal do Paraná – Campus Dois Vizinhos, nos anos de 2012 e 2013, buscando analisar os efeitos da época de semeadura, espaçamento e densidade de cultivo do crambe, o consumo hídrico da planta e análise fisiológica das sementes produzidas. As épocas de semeadura foram de 28 de março a 08 de junho sendo realizados a cada 15 dias. Os espaçamentos de 17 e 51 cm e densidades de 60, 80, 100, 120 e 140 sementes m-2. Foram avaliados os parâmetros produção, germinação, índice de velocidade de germinação, comprimento de plântulas e matéria seca das plântulas. A melhor época observada de semeadura foi a segunda semana de março. Não houve efeito significativo do espaçamento sob a produtividade. As densidades de 100 a 140 sementes m-2, apresentaram os melhores resultados. O Kc foi de 0,64 até o início de florescimento, 0,84 até início da frutificação e 0,79 até início da senescência. / The crambe (Crambe abyssinica) presents itself as a full potential for this end and also it’s a great alternative to the second harvest, the fall/winter´s culture and crop rotations. Crambe shows many good characteristics that are very interesting for the producer, among them are: high concentration of fat in the seed, low production cost, high tolerance to hydric stress, simplicity and precocity. The main objective was to define the spacing and density for the Southwest region of Paraná, and also determine the plantation period as well it´s effects over the quality of the seeds, furthermore the determination of the hydric consumption and culture rate. Four other experiments were conducted at Universidade Tecnológica Federal do Paraná – Campus Dois Vizinhos, in the years 2012 and 2013, seeking to analyze the effects in the plantation period, spacing, density, water consumption and the physiologic analysis of the produced seeds. The planting occurred between March 28th until June 8th each one being planted every 15 days. The spacing were from 17 and 51 cm. and densities of 60, 80, 100, 120 and 140 seeds per m². The analysis of the seed consists in: Germination, index of germination speed, length of the seedlings and dry matter of the seedlings. The best period for both of planting as quality of the production itself was in the second week of March, the spaces did not interfere and the best densities are 100 to 140 seeds per m². The Kc was 0,64 until the blossoming, 0,84 until the fructification and 0,79 until ripeness.

Magister Commercii - MCom / Oilseed is the third most important export item in Ethiopian foreign trade. It has registered a high export growth rate over recent years both in terms of volume and value. Besides its growing share in export, it is widely used for the extraction of edible oil and oilcake that is supplied to the domestic market. Although farmers are the primary producers of oilseeds, they are not able to benefit from the growing market share of the product due to the fact that they find themselves at the end of an extended market chain. As a result they only receive a very small proportion of what the final buyers are paying for the oilseed products. In addition, there is not much experience on the part of the farmers to process oilseeds, change it to edible oil and oilcake and retain the value addition in the local economy. This thesis used the value chain approach to investigate the possibilities for the primary producers to increase their income share from the selling of their products either by directly selling to exporters or by processing oilseeds, producing edible oil and oilcake, and retaining the value addition in the local economy. / South Africa

The overriding objective of this study was to induce genetic variation in Vernonia (Vernonia galamensis variety ethiopica) using ethylmethanesulfonate (EMS) and select mutants for subsequent selective breeding. Vernonia is an underutilised, potential novel oilseed crop with multiple applications in industry mostly due to the production of naturally epoxidised vernolic acid oil. Commercial cultivation of vernonia is significantly hampered by non-uniform seed maturity, tall plant height, seed shattering and lack of appropriate technologies for mechanical harvesting, seed threshing and cleaning. Mutations of a single or few genes possessing target traits are invaluable in crop improvement programs. Chemical mutagenesis using EMS is an important, affordable and effective method to induce random useful genetic mutations in crop plants. Ethylmethanesulfonate mutagenesis has previously been reported to affect various agronomic traits, induce a wide variety of phenotypic mutations and alter both seed oil content and fatty acid profile on several crops. The objectives of this study were: (i) to determine an optimum EMS treatment combination i.e. exposure duration, temperature and dose that would enable 50-60% germination at minimum days to emergence in selected V. galamensis var. ethiopica lines (Vge-1, Vge-4, Vge-7 and Vge-10), (ii) to induce genetic variation using predetermined optimal treatment conditions and select mutants in V. galamensis variety ethiopica lines (Vge-1 and Vge-4) and (iii) to evaluate oil content and fatty acid compositions among seeds of chloroplast mutants, EMS treated seeds and untreated controls of Vge-1 and Vge-4. Before any mutation is administered in plants, it is important that the optimal mutation dose is determined. The lethal dose 50 (LD50) was the standard used in this study to find optimal treatment conditions. Significant interactions (P<0.001) existed between EMS, line, time and temperature with respect to days to 50% emergence, germination percentage and seedling height. Optimal days to 50% emergence (10-12 days) and germination (50- 58%) was achieved for Vge-1, Vge-7 and Vge-10 when treated with 0.372% EMS at 350C for 1 hour treatment. The optimal treatment combination for Vge-4 was 0.372% EMS at 32.50C for 2hr. The treatment combinations that yielded optimum results in the tested lines were utilized to induce large scale mutations in V. galamensis to select target mutants in the field. Large scale mutation was conducted using the observed optimal treatment conditions. Ethylmethanesulfonate mutagenesis significantly delayed days to head formation, days to flowering and days to maturity on both lines. Delays in days to emergence were only significant in Vge-4. EMS treatment also significantly reduced germination percentage, number of seeds per head, number of fertile plants, plant height and plot yield for both Vge-1 and Vge-4. Thousand seed weight significantly increased in treated seeds of the two lines. Chlorophyll mutants were observed for tested lines associated with high count of sterility for both lines. Ethylmethanesulfonate successfully induced phenotypic mutation in selected vernonia lines, however at this stage the effect of mutation on vernonia seed oil content and fatty acid was unknown. Liquid gas chromatography method was employed for oil and fatty acids analysis. In Vge-1, significant differences were observed in composition of linoleic and oleic acid due to the mutagenesis. Significant increases in linoleic and oleic acid composition were found in chloroplast mutants due to EMS mutagenesis. No significant differences were detected in fatty acid compositions in Vge-4 after the EMS treatment. Differential responses were observed when lines were compared at various EMS mutation levels showing significant effect on vernolic, linoleic and oleic acids compositions. In both lines no differences were detected on seed oil content, palmitic acid, steraic acid and arachidic acid compositions after the treatment. Oil content significantly and positively correlated with vernolic acid for Vge-1 (P<0.001; r= 0.898) and Vge-4 (P<0.05; r= 0.65). Vernolic acid significantly and negatively correlated with other fatty acids. The study found that EMS mutagenesis significantly changed the oleic acid and linoleic acid compositions in vernonia. However, the oil content and vernolic acid composition were not significantly affected by EMS treatment. This study established that EMS was successful in inducing genetic variation (in agronomic traits, seed oil content and fatty acid composition) in the two tested lines of V. galamensis. Data from a single planting generation is insufficient to conclude fully on the effect of EMS on V. galamensis; therefore it is highly recommended that further multigenerational studies should be conducted with an increased number of testing lines from a wide range of environmental backgrounds. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

Thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Engineering at the School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand Johannesburg, South Africa October, 2017 / The significant increase in the primary energy demand and the effort to reduce harmful emissions related to the greenhouse gases enhanced the search for alternative energy. Production and modelling processes of biofuel from non-edible oil sources assist in the process development of an environmentally friendly fuel such as biodiesel. This work focused on the kinetic modelling of biodiesel synthesised from non-edible oils. Two types of non-edible oils (Jatropha curcas seed oil and Tobacco seed oil) were used in this study including the development of the kinetic behaviour of the transesterification reaction. A linear polynomial model was generated from experimental data found in literature in order to study the influence of operating parameters during biodiesel production. It was found that the temperature improves the yield of biodiesel; this is attributed to the fact that temperature affects the reaction rate constants; and the higher the reaction rate, the lower the activation energy required for a reaction to occur. The optimum conditions for the transesterification of Jatropha curcas seed oil are a temperature of 55 0C, methanol to oil ratio of 6:1, catalyst concentration of 1.2% KOH (by volume of oil), and agitation speed range of 0-250 rpm. Results from both the homogeneous and heterogeneous reactions of Jatropha curcas oil and tobacco seed oil were used to verify the theoretical kinetic and empirical models. It was found that both models describe the kinetic behaviour of transesterification with minor deviations in the estimated parameters. However, the use of empirical model in determining the reaction order, as opposed to the theoretical assumption, gave a second order with respect to oil triglycerides at a temperature of 60 0C. The theoretical kinetic model gave a first order with respect to oil triglycerides. In this case, the activation energy was found to be 71.83 kJ/mol and pre-exponential factor was found to be 2.48 x1010. More investigation should be done to describe the kinetic behaviour of biodiesel production from non-edible oil in order to confirm the correct reaction order and why there is change in reaction order when the temperature increases above 60°C. / MT2018

Thesis (doctoral)--Georg-August University of Göttingen, 2001. / Includes bibliographical references (p. 106-116).

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