The reproductive biology of macadamia

Macadamia is a widely-grown tree crop that produces edible kernels with high oil content. The macadamia kernel is the single embryo of the fruit, and so factors that influence fruit set and embryo development are critical regulators of yield and quality. This review summarises over 75 years of research on floral induction, floral structure, pollen transfer, the breeding system and fruit development of macadamia, highlighting features such as insect pollination and partial self-incompatibility that limit orchard productivity and affect kernel quality.

► This review describes flowering, pollination and fruit development of macadamia.
► Macadamia is bee-pollinated, partially self-incompatible and primarily outcrossing.
► High yield requires heavy flowering, active pollinators and cross-pollination.
► Flushes of young leaves during floral induction or fruit growth can reduce yield.
► Inter-planting of cultivars and introduction of bee hives may increase yield.