SH1 leaf rust and bacterial halo blight coffee resistances are genetically independent

ABSTRACT Coffee resistance to Pseudomonas syringae pv. garcae has been associated to pleiotropic effect of SH1 allele, present in coffee plants resistant to certain races of Hemileia vastatrix, the causal agent of leaf rust, or genetic linkage between resistance alleles to both pathogens. To validate this hypothesis, 63 coffee plants in F2 generation were evaluated for resistance to 2 isolates of H. vastatrix carriers of alleles, respectively, v2, v5 (isolate I/2015) and v1; v2; v5 (isolate II/2015) with the objective to confirm presence of SH1 allele in resistant plants to isolate I/2015. The...