Influence of Storage Duration and Storage Temperature on Pollen Viability of Kiwifruit (Actinidia deliciosa)

Kiwifruit is a dioecious plant species, requiring cross pollination for fruit production. The objective of this study was to evaluate effects of temperature and duration storage on viability of ‘Tomuri’ pollen grains. Collected pollen grains were stored for 1, 2, 3 and 15 days in room temperature; 3, 15, 30, 45 and 60 days in 4°C and 3, 30, 60 and 180 days in -20°C. This research was carried out using completely randomized design with 12 treatments and three replications. Germination percentage and length of pollen tube decreased with increasing temperature and pollen storage period and an inverse relationship between germination percentage and pollen length with storage period was observed. The pollen tube growth was more affected by duration and temperature of the pollen storage compared to germination percentages. At room temperature, the germination percentage of pollen reached zero after 15 days. After one month of pollen storage at 4°C, growth of pollen tubes declined sharply and reached to the lowest levels among treatments. After six months months of pollen storage at -20 °C, percentage of germination was 65% and length of pollen tube was 380 μ. According to the results, the Tomuri pollen grains can be stored for up to three days at room temperature and for a long time at -20 °C after drying.