| Título: | Insect Resistant Maize for Africa, Annual Report 2001 |
| Autores: | |
| Fecha: |
2014-03-13 2014-03-13 2002 |
| Publicador: |
KARI CIMMYT |
| Fuente: |
Ver documento |
| Tipo: | Books and monographs |
| Tema: |
Africa Kenya Maize Zea mays Plant production Food production Food security Production factors Pests of plants Plant breeding Transgenic plants Pest resistance Biological control Bacillus thuringiensis Production increase Yield increases Diffusion of research Technology transfer Innovation adoption Research projects |
| Descripción: |
The Insect Resistant Maize for Africa (IRMA) Project is a joint venture between the International Maize and Wheat Improvement Center (CIMMYT) and the Kenya Agricultural Research Institute (KARl), with financial support from the Syngenta Foundation for Sustainable Agriculture. It responds to the need to feed Africa's rapidly increasing population by reducing the damage incurred by the region's major insect pest of maize, the stem borer. IRMA is being implemented initially in Kenya, but the results and experiences gained through the project will be made available to other African countries. The overarching goals of the project are to develop insect resistant maize varieties for the major Kenyan maize growing environments and to establish procedures to provide insect resistant maize to resource poor farmers in Kenya. During the implementation of the IRMA project, relevant technologies will be transferred to KARl and continuously evaluated. The specific objectives of the project are the following: (1) Product Development: develop insect resistant maize varieties for the major insect pests found in Kenyan maize production systems. (2) Product Dissemination: establish procedures for providing insect resistant maize to resource poor farmers in Kenya. (3) Impact Assessment: assess the impact of insect resistant maize varieties in Kenyan agricultural systems. (4) Technology Transfer: transfer technologies to KARl and Kenya to develop, evaluate, disseminate, and monitor insect resistant maize varieties. (5) Project Documentation and Communication: plan, monitor, and document processes and achievements for dissemination to the Kenyan public and developing countries. In 2001, the genetic engineering team produced BC4 level backcrosses of the first generation cry gene events, produced single combinations of all first generation events, and characterized all first generation events at the molecular level. Development of second generation "clean" gene events for cryIB and cryIAb continued and six events were identified as negative for the bar gene but positive for crylB gene and effective in controlling southwestern corn borer (the insect species used in Mexico to detect the presence of active cry genes ). A major achievement was the successful completion of the insect bioassays in Kenya. This was possible following the approval of an application to the Kenyan Biosafety Committee for the importation of Bt maize leaves containing six different cry gene events. After permission was received, the necessary permits from Kenyan authorities were granted, and the bioassays were performed in the newly constructed biosafety level-2 laboratory at NARL. The results from the bioassays provided excellent information on which of the various cry genes are most effective against five target insect pests in Kenya. This data is critical to determining which cry genes should be imported into Kenya and incorporated into local germplasm. During 2002, the genetic engineering group plans to submit an application for importing transgenic seeds of second-generation events (cryIAb and cryIB) and a second application to import leaves from crosses of first generation events and to perform bioassays of these. Clean events will continue to be developed for cryIB, cryIAb, and the fusion protein cryIB-Iab. Given the low level of activity of the available cry genes against some of the stem borers, efforts will be made to acquire other cry genes (e.g., cryIAa, cryIC, cryIF, cry2A) from public and private sources. Both Mon810 (cryIAb) and Herculex (cryIF) events have been commercialized in the USA and other countries. Efforts will be made to acquire permission to use these events for testing against Busseola fusca and with possible combinations of other cry genes. Before any Bt maize can be evaluated under field conditions, the KARl Institutional Biosafety Committee requires that it be evaluated in a biosafety greenhouse. Thus, a biosafety greenhouse will be built at the KARl Biotechnology Center in Nariobi. The consultant who developed the initial designs for the greenhouse and laboratories will be contracted to oversee the completion of the greenhouses in 2002. Training of technical staff will continue, especially on the operation of the biosafety greenhouse and molecular analyses of transgenic maize. Development of the facilities for molecular analyses will be initiated. A freedom-to-operate review of Bt maize for Kenya was performed to ascertain what intellectual property considerations might come into play with the introduction of Bt maize developed by the IRMA project and introduced into Kenya. The report reflected the view that the IP issues related to the release of IRMA Bt maize in Kenya appear to be "relatively uncomplicated." CIMMYT's IP Counsel is following up on specific issues raised by the audit with KARl staff. A major activity in 2001 was the development of sources of insect resistance by searching for sources of resistance and by development of source germplasm. Another activity was the search for stem borer resistance among elite germplasm, which farmers can use immediately. In the search for and development of sources of insect resistance, 216 genotypes from CIMMYT and KARl, 42 multiple borer resistant (MBR) 54 lines from CIMMYT Mexico, and 500 MBR/MDR inbred lines from Mexico were evaluated for adaptation, resistance to Chilo partellus and Busseola fusca, leaf toughness, low-N tolerance, and resistance to Turcicum. Crosses were also made to two testers. Good lines will be used to form synthetics and hybrid combinations as sources of resistance. An activity aimed at a value added trait was the screening of germplasm from trials for weevil resistance in kernels. These activities will continue in 2002. Studies were initiated to develop insect resistant management (IRM) strategies for Kenyan ecosystems based on existing cropping systems. To be accepted by farmers, IRM strategies must conform to existing cropping systems, and the refugia crops must be economically viable and socially acceptable to those making the management decisions at the farm level. Studies focused on verifying these tenets were also initiated. After evaluating 30 different alternate hosts for stem borers, preliminary results show Columbus and Sudan grasses as the most effective refugia for C. partellus and B. fusca. Sorghum was the best host for C. partellus and B. fusca based on the large number of exit holes per stem and numerous tillers. Napier grasses attracted oviposition, but were not good hosts for larval development. On environmental impact, the IRMA project is committed to determining what, if any, effects transgenic maize will have on the local ecosystems. In 2001, research focused on establishing the diversity and relative abundance of target and nontarget organisms that could potentially be affected by the introduction of Bt maize into Kenya's major maize cropping systems. Using pit-fall traps to trap crawling arthropods, water traps and sticky traps for flying arthropods, and destructive sampling to recover organisms on and in the plant, a diversity of organisms associated with maize cropping systems were recovered, characterized, and, catalogued and will serve as a technical reference during the monitoring phase of the IRMA project. The Kitale and Machakos sites were added in 2001. The Embu site will follow in 2002. Development of numeric and digital databases on the collection as well as development of a reference collection will be major activities for 2002. A study evaluating Bt biopesticide and conventional insecticides for the management of stem borers and the nontarget effects on arthropods in a maize/bean cropping system revealed that Bt spray was more effective in controlling stem borers while preserving a greater number of parasitoids compared to synthetic insecticide treated plots. IRMA's impact assessment group composed of social scientists focused on assessing various aspects of insect losses, suitability and demand of the new insect management technologies, farmers' perceptions of crop losses and control options, and assuring that the technology fits within Kenya's institutional framework. Through continuous dialogue with different stakeholders such as environmental groups, local research institutes, seed companies, and above all the farmers, IRMA has gained a clearer understanding of social, environmental, and economic impacts of insect resistant maize in Kenya. Participatory Rural Appraisals (PRAs) were organized in the five maize agroecological zones of Kenya. They identified farmers' preferences for maize varieties, the criteria they use to select varieties, and the major maize production constraints they face. The major pest problems, according to farmers, are stem borers and weevils. Farmers show a keen interest in new insect resistant varieties if they fit their selection criteria, even if they are moderately more expensive. However, since seed supply and quality are problems, the quality of seed needs to be guaranteed. Results of the maize sector study show that although most restrictions on maize marketing have been lifted, and that markets for fertilizer and pesticides are fairly free, poor infrastructure, market information, and access to rural credit markets remain problematic. The crop loss at the national level due to stem borers is estimated at approximately 13%, with a value of U5 72 million (as of 2001; further study may result in a revision of this figure). Crop loss assessment will continue. A baseline survey will be the major focus in 2002. As we are dealing with new technology, technology transfer and capacity building in local institutions is critical to success and sustainability. Training of KARl scientists was done in Mexico and on site in Kenya. Two scientists from KARl trained in insect bioassays and biosafety greenhouse operations. Infrastructure support and development were realized through the planning of laboratories for the KARl Biotechnology Center, development of a biosafety level-2 laboratory, provision of computing and communication equipment, vehicles for transport, laboratory equipment, and support of the insectaries and entomology laboratories at two KARl centers. The capacity for mass rearing various stem borer species for resistance screening studies, insect bioassays, and for resistance management studies was improved. During 2001, production was increased and rearing of B. ftlsca improved. Better records are being kept and synchrony of demand and supply has thus improved greatly. Considerable effort has been given to creating dialogue and raising public awareness about Bt and insect resistant maize and biotechnology in general. Communication has been emphasized through stakeholders meetings, efforts aimed at positive media relations, creation of print and electronic materials, interactions with the local press to achieve objective coverage, and participation and documentation of IRMA-related seminars and conferences. In 2002, emphasis will be given to creating awareness among extension staff and developing strategies to reach farmers. In conclusion, apart from the somewhat slow pace of actually introducing Bt maize in Kenya, the objectives of the IRMA project were largely met. These activities and achievements have moved the IRMA project toward achievement of its goal and objectives. |
| Idioma: | English |