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Cultivars of Prunus armeniaca have a wide geographical distribution. Their cultivation under conditions of a dynamically changing climate, various soil types, and the increasing demand for higher productivity necessitates the use of a diverse range of rootstocks. During the period 2022–2024, a study was conducted in a fruit tree nursery located in Central South Bulgaria to assess the influence of different rootstocks on the growth characteristics of the apricot cultivar ‘Hargrand’. The following combinations were evaluated: rootstocks GF677 and GXN15 (Garnem) with interstocks ‘Stanley’ (Prunus domestica L.) and ‘Redhaven’ (Prunus persica Batsch.); Мyrobalan seedling rootstock (Prunus cerasifera Ehrh.) with ‘Stanley’ as an interstock; and the commonly used Мyrobalan seedling rootstock without interstock.
The lowest bud-take rate for ‘Hargrand’ was recorded on Мyrobalan seedling rootstock, both with and without ‘Stanley’ as interstock (78–83%). Higher bud-take rates (84–88%) were observed in the other combinations. Regarding vegetative growth, all tested variants produced trees of acceptable size for planting in commercial orchards. The best branching potential was observed in trees budded on the peach–almond hybrid rootstocks GF677 and Garnem, combined with the interstocks ‘Stanley’ and ‘Redhaven’, while the weakest branching was noted in trees on Мyrobalan seedling, both with and without an interstock.
Keywords: Prunus armeniaca, rootstock, interstock, GF677, Garnem, lateral shoots, nursery