The most crucial factor in producing papaya seedlings successfully is seed germination. The purpose of this study was to investigate the influence of seed priming with growing media on seed germination and seedling growth of papaya from October to December 2022. The experimental treatments included three seed priming treatments: T₀ = control (no seed priming treatments), T₁ = GA₃ (100 ppm), and T₂ = KNO₃ (1%), and four growing media, viz., M₁ = soil + vermicompost (1:1), M₂ = soil + cowdung (1:1), M₃ = soil + cocopeat + vermicompost (1:1:1), and M₄ = soil + cocopeat + cowdung (1:1:1). The treatments showed a significant effect on different parameters such as germination percentage, days to germination, survival percentage, chlorophyll content, seed vigor index, shoot, and root length. GA₃ treated seedlings performed better than non-GA₃-treated seedlings. Among the growing media, M₃ showed the best for seed germination and other growth attributes compared to other growing media. In terms of interaction effects, T₁M₃ showed the highest performance for germination percentage (84.33%), survival percentage (91.0%), and chlorophyll content (44.26%). T₁M₃ also showed the highest seed vigor index, shoot and root growth, and plant biomass. As a result, the combination of GA₃ and growing media containing soil + cocopeat + vermicompost was shown to be the most favorable for papaya seed germination and seedling growth.

Low temperature is one of the most significant environmental factors that threaten the survival of subtropical and tropical plant species. By conducting a study, which was arranged in a completely randomized design with three replicates, the relative freezing tolerance (FT) of four Iranian pomegranate cultivars, including ‘Alak Torsh’, ‘Tabestaneh Torsh’, ‘Poost Sefid’, and ‘Poost Syah’, as well as its correlation with some biochemical indices, were investigated. From each cultivar, pieces of one-year-old shoot samples were treated with controlled freezing temperatures (−11, −14, and −17 ℃) to determine lethal temperatures (LT₅₀) based on survival percentage, electrolyte leakage, phenolic leakage, and tetrazolium staining test (TST) methods. Results showed that FT was higher in the second year with a lower minimum temperature and a higher concentration of cryoprotectants. The stronger correlation of electrolyte leakage with survival percentage (r = 0.93***) compared to the other three indices explained that this index could be the most reliable injury index in determining the pomegranate FT to investigate freezing effects. Of all four cultivars, ‘Poost Syah’ was the hardest by presenting a higher FT than ~ −14 ℃ in mid-winter. Accordingly, this pomegranate cultivar seems to be promising to grow in regions with a higher risk of freezing and to be involved in breeding programs to develop novel commercial cultivars.