Viabilidade de pólen de milho em diferentes períodos de armazenamento em baixa temperatura

Abstract

Pollen grain storage is justifiable in maize breeding programs due to the non-coincident flowering of lines and/or cultivars to be bred. Thus, pollen storage techniques have been developed which preserve pollen efficiency. The aim of this work was to verify the viability of stored pollen through in vivo and in vitro tests. Pollen grains of four maize cultivars were stored in freezer for 2, 4, 8, 14 and 15 days. Pollen viability was assessed through determination of seed production per ear, color tests and in vitro pollen germination. The percentage of in vitro pollen germination and seed production, independent of storage time, was 13 percent on average. In the color test, all analyzed cultivars presented more than 95% viability, independent of in vitro germination percentage and seed production per ear. The storage of maize pollen is a viable procedure; however, it is necessary to adjust the storage techniques, as well as the tests for assessing pollen viability.