Includes bibliographical references (p. 159-167).

The aim of the thesis is to investigate the barriers to, and the driver of, the adoption of organic agriculture, especially from the point of view of agricultural professionals (scientists, researchers, academics and extension officers). The thesis also summarises the economics of organic agriculture, and provides a unique case study on organic viticulture in Foster's Clare Valley Estare from the 1980s to mid 2000. / Thesis (PhD)--University of South Australia, 2006.

Thesis (M.S.)--West Virginia University, 2005 / Title from document title page. Document formatted into pages; contains vii, 51 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 46-51).

Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains vii, 73 p. : ill. (some col.). Includes abstract. Includes bibliographical references.

Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Clain Jones. Includes bibliographical references.

Field trials were conducted in 2010/11, 2012 and 2013 at the Royal Agricultural University’s Soil Association certified organic Harnhill Manor Farm, Gloucestershire, UK (NGR SP 075 006), to investigate suitable cultivation techniques and legume cover crops for winter and spring wheat production. Cultivation treatments included conventional tillage (CT), low residue non-inversion tillage (LRNiT) and high residue non-inversion tillage (HRNiT) as main plots while undersowing white clover (WC), black medic (BM) or no undersowing (Nus) as subplots. Wheat establishment, growth, grain yield and weeds infestation were assessed to determine the feasibility of these husbandry techniques. For winter wheat in 2010/11, LRNiT seems to be an acceptable alternative for CT. However, for spring wheat in 2012 and 2013, CT seems to be more reliable management option. The performance of undersown legumes was highly weather reliant and inconsistent in the seasons studied. Plant establishment and the succeeding yield parameters were positively related to grain yield. CT had significantly higher plant establishment than LRNiT or HRNiT in each season. For winter wheat, the competition and compensation on shoot density among CT and LRNiT did potentially outweighed cultivation-induced effects on plant establishment. This condition resulted in statistically equivalent crop growth and yields with LRNiT to that of CT. In contrast, for spring wheat in 2012 and 2013, CT that had significantly higher plant establishment also resulted in better crop growth and greater grain yields than other cultivation treatments. In all seasons, HRNiT had significantly lower plant establishment and also reduced grain yields, compared with LRNiT or CT. More soil cultivation also significantly reduced total weeds than less tilled soil such as HRNiT. On the basis of weed species, significantly higher broadleaf weeds were present under CT and significantly higher grass weeds were present under HRNiT. Out of three investigated years, legume cover crops effects were clearly observed only in 2012 with spring wheat. More vigorous growth of WC showed a significantly inverse relationship with broadleaf weeds and total weeds, compared with slow growing BM. This situation, resulted in non-significant yield components or grain yield reduction, compared with non-undersown spring wheat. In this context, white clover seems to be more suitable legume cover crop than black medic.

There is growing evidence that the way that the world produces and consumes food needs to change. There is growing public awareness of serious environmental threats (e.g. global warming, loss of biodiversity and pollution) as well as social concerns (e.g. poverty, inequality and food security). It is necessary for global agriculture to rethink its approach to food production and to find new ways of producing food that can meet the demands of the growing world population and at the same time reduce the environmental degradation caused by farming. So called green revolution technologies, resulting in high intensity, high input agriculture are damaging the very resources on which agriculture depends; soil and water. Research reveals current conventional practices to be unsustainable. There is a growing recognition, arising from the creation of new knowledge and the development of deeper understanding, that this change is necessary and urgent. Organic (or ecological) farming has emerged as a more beneficial way of producing food from a social and environmental perspective. Demand for, and production of, organic food grew steadily in the second half of the twentieth century and has increased dramatically in the twenty first century. This can largely be ascribed to social learning processes. This growth is not yet reflected in South African agriculture. Given the advantages of organic agriculture, it is necessary to consider how to accelerate its expansion. Understanding the social learning processes of organic farmers and using learning histories are useful tools to create a better understanding of how this can be achieved. The objective of this dissertation is to make use of four social learning frameworks to enhance the understanding of the social learning dynamic of organic farmers by: • Using existing baseline data from a survey of the organic farming sector to draw out the learning histories. • Developing an understanding of four social learning frameworks. • Combining the learning histories and the understanding of social learning frameworks to form a deeper understanding of the social learning dynamics in the South African organic agricultural sector. A literature review of the organic sector and of four learning frameworks (profound change, conversion of knowledge, deeper learning, and the pedagogy of adult social learning) is used to develop an understanding of the essence of organic agriculture and how people learn. Information from a survey of organic farmers in South Africa, is used to impregnate the learning frameworks in order to develop an understanding of how organic farmers in South Africa are learning Open-ended questions from the survey are analysed and interpreted based on the understanding of learning frameworks. Selected statements that reflect social learning are highlighted, incorporated into the learning frameworks and discussed to better understand how organic farmers are learning. The analysis indicates that a high proportion of organic farmers are social learners. The four frameworks demonstrate that many organic farmers see their role as more than just providers of food. They also see themselves as custodians of the land with a deep concern for the environment. Fewer organic farmers demonstrate an understanding of social issues. Those that did showed a clear understanding of the need to integrate social considerations into food production. Networking and sharing of learning are important methods of knowledge creation among organic farmers as a result of the limited research and support for organic farmers in South Africa. Recommendations to accelerate and understand the learning by organic farmers and consumers are provided. Future research is suggested in order to investigate how to assist organic and conventional farmers to better understand learning, identify how learning can be enhanced or retarded, and actively engage in learning that facilitates knowledge creation. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed January 20, 2010). Thesis advisor: Dr. Georgeanne Artz. Includes bibliographical references.

Thesis--Auburn University, 2008. / Abstract. Includes bibliographic references (p.57-67).