Indirect Versus Direct Selection of Adaptable Genotypes of Coffea canephora for Drought Stress and Non-Stress Conditions

Improving breeding strategies for adaptation to water-deficit stress is an important challenge to increasing coffee yields. In a nine-year experiment, 18 genotypes were tested under drought-stress and non-stress conditions to select adaptable genotypes to drought stress. Efficiency of indirect selection based on agronomic traits related to drought-stress was also assessed relative to direct selection based on yield. Drought stress significantly limited fruit-set and yields by 51–75% in all 18 genotypes. Clustering the genotypes based on seven-year average yields under stress and non-stress conditions and their drought susceptibility index (DSI) resulted in the direct selection of eight generally adaptable genotypes. These were characterized by low DSI and high yields in drought-stress and non-stress environments. These genotypes should serve as materials for breeding for drought tolerance or for direct utilization as planting material under drought-stress and non-stress conditions. The first three-year av...