Effects of Self-pollination and Cross-pollination of Vaccinium darrowii (Ericaceae) and Other Low-chill Blueberries

Abstract

Partial to complete self-incompatibility is normal in most Vaccinium L. (Ericaceae) species. Wild blueberry plants of several Florida provenances and species were self- and cross-pollinated in a greenhouse free of pollinators. Fruit set of V. darrowii Camp (2x), V. corymbosum L. (4x), V. arboreum Marsh (2x), and F1 (V. darrowii × V. corymbosum) hybrids was higher after cross-pollination than after self-pollination. Partial to complete self-incompatibility was present in V. darrowii, V. corymbosum, and their tetraploid F1 hybrids. The three V. arboreum clones tested were fully self-incompatible. Intra- and interpopulation crosses in V. corymbosum, V. darrowii, and V. darrowii × V. corymbosum hybrids were highly successful, and self-pollination reduced all fertility parameters. Advanced selections of V. corymbosum were the most self-compatible clones tested, possibly because self-compatibility has been increased by breeders selecting for reliable fruit set in large fields planted with one or a few clones. One southern highbush selection and two F1 hybrids had fruit set of more than 70% after self-pollination. These plants could be potentially used to breed plants that could be planted in single blocks providing reliable yield.