‘Rootpac R’ for Apricots? Yes!

The rootstock ‘Rootpac R’ is not used for apricots. The aim of this study was to evaluate the characteristics of ‘Rootpac R’ in comparison to the widely used ‘Myrobalan 29C’ rootstock. The evaluation of the rootstocks was conducted in combination with 16 scion cultivars to assess their effects on vegetative traits and mortality. The total height of the trees on ‘Rootpac R’ initially surpassed the ‘Myrobalan 29C’ trees. By the end of the fourth year, both rootstocks showed comparable heights with ‘Rootpac R’ standing at 317 cm and ‘Myrobalan 29C’ standing at 307 cm. Both rootstocks exhibited comparable TCSA values of 5 cm2 initially; ‘Rootpac R’ surpassed 35% compared to ‘Myrobalan 29C’. Canopy space occupancy assessments revealed that ‘Rootpac R’ initially demonstrated superior space utilization, occupying 8% of the designated volume compared to 4% for ‘Myrobalan 29C’. By the fourth year, ‘Rootpac R’ exhibited a higher occupancy rate of 65% compared to 50% for ‘Myrobalan 29C’. For apricot cultivars, such as ‘Bergeron’, ‘C. óriás’, ‘Gönci magyarkajszi’, ‘Lady Cot’, ‘Tardif de Valance’, and ‘Tom Cot’, ‘Rootpac R’ exhibited survival rates beyond the fourth season, highlighting its effectiveness for these varieties. Based on these results, ‘Rootpac R’ rootstock could be useful in apricot growing.