Project Number: 6631-21000-017-19
Project Type: Specific C/A

Start Date: Sep 28, 2006
End Date: Sep 27, 2011

Objective:
Utilize the three new QTLs identified for resistance to frosty pod disease at Miami to select in breeding populations for resistant genotypes. Validate the efficiency of selection from the markers with phenotypic data from field screenings. Continue with the evaluation for yield and quality characteristics. Increase the data analysis capacity with our collaborators in Ecuador at the INIAP Research Station that are also selecting for frosty pod and witches broom resistance.

Approach:
The partial evaluation of an 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, comprising approximately six hectares of land where selected families known to be segregating for resistance, have been planted and partially evaluated. Four grafted plants per tree plus the original seedling permits 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 for the next five years 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, Ecuador that complement the work in Costa Rica.