Almond pollination studies: pollen production and viability, flower emergence and cross-pollination tests

Abstract

During 1978-80, flower emergence was recorded on 12 almond cultivars (Prunus dulcis) at Angle Vale, South Australia. Early flowering cultivars showed a larger annual variation in flowering period (2-3 weeks) than late flowering cultivars (0-2 weeks). In the same period, pollen production ranged from 30 to 122 mg per 100 flowers and in vitro pollen germination ranged from 76.1 to 99.0%. Pollen production and in vitro germination differed significantly between cultivars. Hand-pollination of Nonpareil with pollen from each of eight other cultivars resulted in significantly higher nut set than with open-pollinated or self-pollinated flowers. In contrast to Nonpareil, hand-pollination of Chellaston with pollen from five other cultivars resulted in significantly higher nut set compared with self-pollinated Chellaston but not compared with open-pollinated Chellaston. The potential increase in almond yield due to improved pollination is discussed.