Tolerance — Prunus amygdalus x Prunus persica

To evaluate the tolerance of these hybrids, physiological and biochemical markers such as proline and polyamine content, as well as the activity of antioxidant enzymes, are used. Salinity tolerance is assessed by the electrical conductivity threshold of the soil solution, which reaches 3–4 dS/m. Laboratory methods include the use of osmotic agents like PEG 8000 and NaCl to analyze survival and root formation, while field methods focus on the degree of chlorosis, growth vigor, and bud graft survival.

The level of tolerance varies depending on the clone and environmental factor. Hybrids such as GF-677 demonstrate high resistance to high lime content, preventing iron-deficiency chlorosis, whereas other forms may be less effective. Most representatives of the group are characterized by low tolerance to waterlogging and root asphyxia. At the same time, some clones, for example Garnem, show pronounced tolerance to root-knot nematodes of the genus Meloidogyne while remaining susceptible to bacterial canker.

Selecting a rootstock with consideration for tolerance allows for the use of sites with alkaline soils and the optimization of irrigation regimes. The use of resistant clones ensures stable scion growth vigor, tree longevity, and high productivity under soil stress conditions, which also influences canopy management strategies due to the high vegetative activity of these hybrids.