Meiotic behaviour of the pollen mother cells in cultured anthers of rye excised at early meiotic prophase

Abstract

Anthers of rye were excised during leptotene and zygotene and cultured in vitro on media with and without indole-3-acetic acid to study the behaviour of pollen mother cells during meiosis. Percentages of pollen sacs in which pollen mother cells continued meiosis increased from approximately 20% to 60–70% when anthers were excised at early and late leptotene. The highest values were about 90% when the excision was during zygotene. The results were similar on both media. The timing of pollen mother cells through meiosis on the hormone-free medium was similar to that described in vivo. The mean numbers of chiasmata per cell at metaphase I from the cultured pollen sacs were compared with those from a random population of pollen sacs grown in the field. A significant decrease was observed when anthers were excised during leptotene and cultured on both media, as well as when anthers were excised at early zygotene and cultured on the hormone-supplemented medium. We concluded that at early zygotene there are processes related to chiasma formation that seem to be influenced by hormone balance.Key words: Secale cereale, anther culture, meiosis development, chiasma formation, indole-3-acetic acid.