Pollen viability and in vitro pollen germination studies of some blueberry cultivars

At least 80% of flowers must set fruit for a viable commercial highbush bluberry crop. Poor pollination is known to give rise to poor berry production. For this reason, insects, specifically bees, are required for pollen transfer. Pollen quality, quantity, and seed formation also vary among cultivars. In this study, pollen viability rate, pollen germination rate, amount of pollen production and normally developed pollen rates were determined at three different periods (first bloom, full bloom and end of bloom) in three southern highbush blueberry cultivars. Pollen viability was determined using the TTC (2,3,5-triphenyl tetrazolium chloride) test; pollen germination was tested in agar-containing petri dish; while pollen production was estimated with the hemacytometric method. The largest number of tetrads per flower and the highest tetrad production were obtained in ‘B0504’ and ‘Ventura’. The results also showed that high pollen production may indicate good pollen quality.