Progress 11/01/01 to 10/31/06
Outputs
Progress Report Objectives (from AD-416) Utilize the three new QTLs for resistance to frosty pod disease identified in Miami to select for resistant genotypes in breeding populations. Use phenotypic data from field screenings to validate the efficiency of selection using the markers. Continue with the evaluation for yield and quality characteristics. Increase the data analysis capacity of our collaborators in Ecuador at the INIAP Research Station that are also selecting for frosty pod and witches broom resistance. Approach (from AD-416) The partial evaluation of a F1 hybrid field trial comprising 34 families and two segregating populations was the most outstanding activity carried out during the period 2004-2005. These new experimental areas, together with other trials established by CATIE during previous years, are the basis of the current and future clonal selection and collaborative studies between the USDA and CATIE. Selection trials for frosty pod resistance comprise approximately six hectares of land. Selected families known to be segregating for resistance have been planted and partially evaluated. Evaluating four grafted plants per tree plus the original seedling allows us to separate and estimate precisely the genetic and environmental components related to outstanding characteristics such as yield potential, disease resistance and industrial quality in individual genotypes within segregating progenies. The maintenance and continued phenotypic evaluation of these families and clones must be continued in FY2006 to evaluate MAS and select superior individuals. Individuals within families are being selected based on molecular markers linked to QTL for frosty pod and witches� broom resistance. These selections are then validated in the field at CATIE. In addition to the work in Costa Rica, collaborative USDA projects exist with INIAP at EET in Pichilingue in Ecuador that complement the work in Costa Rica. Significant Activities that Support Special Target Populations This report serves to document research conducted under a specific cooperative agreement between ARS and the Centro Agronomico Tropical de Investigacion y Ensenanza (CATIE). Additional details of research can be found in the report for the parent project 6631-21000-012-00D Development of DNA markers associated with disease resistance in cacao. This serves as a final report for the project. The project is continuing under the new agreement numbered 6631-21000-012-12S. Five QTL for frosty pod resistance and two QTL for black pod resistance were identified in an F1 population from CATIE. These QTL are now being used in the Marker Assisted Selection program to select for frosty pod resistance. Monitoring Activities: Site visit to review field trials was made in October 2006.
Impacts
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Progress 10/01/05 to 09/30/06
Outputs
Progress Report 4d Progress report. This report serves to document research conducted under a specific cooperative agreement between ARS and the Centro Agronomico Tropical de Investigacion y Ensenanza (CATIE). Additional details of research can be found in the report for the parent project 6631-21000-012-00D Development of DNA markers associated with disease resistance in cacao. Utilizing the five new QTLs for resistance to frosty pod disease identified in Miami we are selecting for resistant genotypes in breeding populations and using the phenotypic data from field screenings to validate the efficiency of selection using the markers. We are continuing with the evaluation for yield and quality characteristics. The partial evaluation of a F1 hybrid field trial comprising of 34 families and two segregating populations was the most outstanding activity carried out. These new experimental areas, together with other trials established by CATIE during previous years, are
the basis of the current and future clonal selection and collaborative studies between the USDA and CATIE. Selection trials for frosty pod resistance is comprised of approximately six hectares of land. By evaluating four grafted plants per tree plus the original seedling we are able to separate and estimate precisely the genetic and environmental components related to outstanding characteristics such as yield potential, disease resistance and industrial quality in individual genotypes within segregating progenies. The maintenance and continued phenotypic evaluation of these families and clones must be continued to evaluate MAS and select superior individuals.
Impacts
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Publications
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Progress 10/01/04 to 09/30/05
Outputs
4d Progress report. This report serves to document research conducted under a specific cooperative agreement between ARS and the Centro Agronomico Tropical de Investigacion y Ensenanza (CATIE). Additional details of research can be found in the report for the parent project 6631-21000- 012-00D Development of DNA Markers Associated With Disease Resistance in Cacao. Using the UF 273 x Pound 7 mapping population, four QTLs were identified for resistance to Frosty Pod disease (FP). These are the first QTLs isolated for resistance to FP. Using a set of existing families, originally produced for the selection of new varieties and having over five years of field data, we were able to estimate Specific and General Combining Ability (SCA & GCA) for agronomic characters and disease resistance. In contrast to reports from the literature SCA was found to be important in cacao. This finding will have a significant impact on the designs used in the breeding program.
Impacts
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Progress 10/01/03 to 09/30/04
Outputs
4. What were the most significant accomplishments this past year? D. Progress Report. This report serves to document research conducted under a specific cooperative agreement between ARS and the Centro Agronomico Tropical de Investigacion y Ensenanza (CATIE). Additional details of research can be found in the report for the parent project 6631-21000- 012-00D, Development of DNA markers associated with disease resistance in cacao. The establishment of a F1 hybrid field trial using 34 families and two segregating populations was the most outstanding activity carried out during the period. These new experimental areas, together with other trials established by CATIE during previous years, are the basis of the current and future clonal selection and collaborative studies between the USDA and CATIE.
Impacts
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Publications
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