|dc.description.abstract||The aim of the research presented in this dissertation was to further the implementation of push-pull for control of Eldana saccharina on sugarcane in the Midlands North region, KwaZulu-Natal, South Africa. Eldana saccharina, an indigenous stem borer, is the most damaging pest of sugarcane in South Africa, and sustainable control has still not been achieved. The push-pull strategy, a form of habitat management, has been developed for E. saccharina and is recommended as part of an integrated pest management (IPM) approach. Implementation of this strategy for both large- and small-scale farmers was facilitated through mixed methods social research. It included a novel exploratory network analysis to understand the process of technology adoption by farmers. Surveys showed that large-scale farmers have a good knowledge of E. saccharina, IPM and push-pull but that they needed more practical knowledge for implementation of the strategy. Farmers recommended experiential learning opportunities such as field days and model farms to get to know more about this technology. Despite demonstrating a positive attitude towards push-pull, farmers perceived it to be a ‘hassle’ and this is potentially the biggest barrier to its adoption. However, with suitable learning opportunities for farmers and good support for planting inputs, implementation of push-pull is likely to succeed. Sugarcane was shown to play an important role in the livelihoods and farming systems of small-scale growers. They did not perceive E. saccharina as a serious production constraint and had poor knowledge of the pest and its control. Extension for small-scale growers in this region should focus primarily on weed management and on reducing input costs, but still raising awareness of the increasing threat of E. saccharina. On-farm push-pull field trials showed a significant reduction of E. saccharina damage on two farms. Mean percentage damaged internodes decreased from 4.1% to 2.7% and from 1.7% to 1.1% in the presence of the repellent grass species, Melinis minutiflora. Where farmers did not manage their crops well, push-pull was not effective. It is therefore crucial that push-pull within an IPM framework be implemented together with good crop management practices.
Stem borer surveys in wetlands on sugarcane farms revealed a high diversity of indigenous stem borers and parasitoids, including a stem borer species, Pirateolea piscator, which may pose a threat to crops in the future. These findings, together with a literature review on the significance of on-farm biodiversity and ecosystem services, demonstrated the value which wetlands have for pest management on sugarcane farms. Wetland health assessments were used to develop a tool for farmers to assess and utilise the wetlands on their farms for improved management of E. saccharina.
This study highlights the importance of a farmer-participatory approach to implementation of knowledge-intensive farming practices such as push-pull. The importance of wetlands for providing pest regulatory services on sugarcane farms has shown that environmental sustainability needs to become a fundamental principle of farming and agricultural research. Participatory implementation of push-pull, as recommended in this dissertation, could act as a driving force for agroecology in the South African sugar industry and move sustainable farming practices off the pages of journals and manuals onto farmers’ fields.||en_US