USE OF MOLECULAR MARKERS TO PYRAMIDING MULTIPLE GENES FOR RESISTANCE TO RUST, ANTHRACNOSE AND ANGULAR LEAF SPOT IN THE COMMON BEAN

摘要

Rust, anthracnose and angular leaf spot incited by the fungi Uromyces appendiculatus, Colletotrichum lindemuthianum and Phaeoisariopsis griseola, respectively, are considered among the most important diseases affecting the common bean (Phaseolus vulgaris L.) in Brazil and in other parts of the world. These diseases may cause losses that can reach 100% depending on the environment and the use susceptible cultivars. The use of resistant cultivars has been considered as an efficient, safe, and inexpensive alternative accessible to bean growers. Combining or pyramiding the different resistance genes in a single cultivar may result into medium to long-tprm control. Recognizing the presence of different resistance genes in a specific cultivar under fieldconditions is extremely difficult. Molecular markers can be used to aid the identification of these genes. They can also be used be to accelerate the recovery of the recurrent parent's genome in backcrossing programs (Faleiro et al., 2004). In this study, DNA fingerprints and molecular marker assisted selection were used to accelerate the development of common bean advanced lines simultaneously resistant to U. appendiculatus, C. lindemuthianum and P. griseola.