The long-term preservation of pollen is very important for breeding purposes, ensuring the pollination of fruit tree orchards, and germplasm exchange. Therefore, the purpose of this research was to investigate the morphology of pollen grains, and the effect of temperature and duration of storage on the survival and germination of some Asian and European pear cultivars pollen also was explored. Morphological characteristics of pollen grains were examined using scanning electron microscopy in a completely randomized design with 3 replications, showing significant differences at a one percent probability level in the polar axis (P), equatorial axis (E), furrow length, ridge width, and furrow depression between cultivars. The changes in the polar axis length ranged from 15.82 to 23.77 micrometers, and the equatorial axis length ranged from 35.86 to 45.39 micrometers, which can help identify cultivars. Moreover, the germination of mature pollen grains under laboratory conditions after 3, 6, 9, and 12 months of storage at three temperatures of 24°C, 4°C, and -20°C showed that with increasing storage time, the germination percentage of all treatments significantly decreased. The percentage of pollen germination after 12 months of storage under room temperature treatment was almost zero, and they lost their viability faster than at -20°C and 4°C, the cultivar KS9 had the highest germination percentage (87.08) at refrigerator temperature, followed by cultivar KS6 with a germination percentage of 81.25 at freezer temperature (-20°C), and cultivars KS13 and KS7 also had the highest germination percentage at 4°C. Therefore, for breeding purposes, germplasm preservation and hybridization between varieties flowering at different times of the year, KS9, KS6, KS13, and KS7 varieties can be used.
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