KNAP2, a class I KN1-like gene is a negative marker of bud growth potential in apple trees (Malus domestica [L.] Borkh.).

The determinism of bud bursting pattern along the 1-year-old shoot was studied at the molecular and morphological levels in the apple tree variety 'Lodi' which shows an acrotonic tendency. At the molecular level, the expression of KNAP2, which belongs to the class I KN1-like gene family, was studied. Measurements were carried out during dormancy (October), breaking dormancy (January) and just before bud bursting (March).