Inheritance of Resistance to Black Knot in Plums

Abstract

Evaluation of progeny resulting from controlled crosses and selfs of various plum (Prunus salicina and hybrids) cultivars revealed that resistance to black knot Apisporina morbosa (Schw.) is controlled by a single recessive gene (proposed designation bk) in the resistant cultivars studied. `Bruce', `Munson', `Crimson', and `Ozark Premier' were homozygous resistant (bkbk), while `Methley' was susceptible and heterozygous (Bkbk) for the trait.