Pollen viability in Kunzea pomifera (Myrtaceae) as influenced by sucrose concentration and storage

Abstract

In vitro germination of freshly collected pollen was examined for five genotypes of Kunzea pomifera in liquid media with 5% and 10% sucrose. There were no significant differences in germination level between the different sucrose concentrations for each of the genotypes. Pollen-germination levels were significantly different among genotypes, ranging from 7 to 89%. Pollen of one genotype, stored for 12 months at 4°C and 10% relative humidity, was evaluated for germination at intervals over this period, and while significant differences in the levels of pollen germination after different storage periods were found, there was no correlation between germination percentage and storage time. Pollen of the K. pomifera accession Kmt1 stored under such conditions for 370 days was used in controlled pollination with accession Kmt2, resulting in 3.4 seeds per fruit, which was significantly fewer than the 17.2 seeds per fruit when using fresh pollen.