Effects of storage temperature and duration on the pollen viability of Phalaenopsis ‘KS Little Gem’
摘要
In breeding, although superior parents are generally selected for cross-hybridization, the pollen of elite cultivars may not always be available. Stored pollen provides a practical solution when freshly harvested pollen is unavailable, ensuring its viability for breeding purposes. In this study, we evaluated pollinia of the orchid hybrid cultivar Phalaenopsis ‘KS Little Gem’ at nine different flowering stages with respect to viability after storage for up to 24 months at different temperatures based on in vitro post-storage pollen germination. We detected considerable variation in pollen germination with respect to flowering stage, storage temperature, and storage duration. Pollen collected at flowering stages 1 to 6 and stored at all assessed temperatures for 2 months remained viable. At all storage temperatures, the highest germination was observed in pollen collected from stage 1 after 1 month of storage. Germination of pollen collected at all flowering stages and stored at all assessed temperatures declined significantly with storage prolongation. Pollen stored at 4°C for longer than 2 months showed a marked loss of viability. At -20°C, pollen collected at stages 1 to 3 remained viable until 12 months, whereas at -80°C, germination of pollen obtained at flowering stages 1 to 5 was observed up until 18 months of storage, although only stage 1 pollen stored at -80°C remained viable after 24 months. Our findings indicate that Phalaenopsis ‘KS Little Gem’ pollen can be stored at -20°C for up to 12 months for short-term storage and at -80°C for up to 24 months for long-term storage.