Sweet cherry (Prunus avium L.) cultivars and rootstocks play a vital role in the fruit industry, yet challenges in large-scale propagation present an opportunity for the application of temporary immersion systems (TIS). This study establishes culture protocols for four genotypes: the rootstocks Maxma-14 and Colt, and the cultivars ‘Van’ and ‘Rainier’. Internodal segments from seedlings maintained in solid propagation medium (PM)—based on DKW and supplemented with indole butyric acid, benzyl amino purine, ascorbic acid, myo-inositol, and agar—served as initial explants.
Explants were cultured under TIS for 14 days, followed by transfer to solid rooting medium for 30 days, resulting in complete plant regeneration. Rooting success varied between cultivars and rootstocks. A subsequent 15-day acclimatization phase enabled successful establishment in greenhouse conditions.
TIS efficiency was evaluated using two optimized PM-derived media and compared to conventional solid medium cultures. Key parameters included shoot number (Px), biomass accumulation (Qx), and sucrose consumption (SC). Maxma-14, Colt, and ‘Van’ exhibited superior performance under TIS relative to solid medium, while ‘Rainier’ showed no significant differences.
Immersion frequency influenced all productivity metrics (Px, Qx, SC); genotype specifically affected Px, and immersion duration impacted SC. The highest Qx and Px values were recorded for Maxma-14, Colt, and ‘Van’, with no signs of hyperhydratation. Physiological assessments indicated that shoots produced via 14-day TIS represented an intermediate developmental stage between solid-derived and mature plants. However, photosynthetic efficiency measurements revealed limited autotrophic capacity at this stage.