Chromosome numbers, meiotic behavior and pollen fertility in a collection of Paspalum nicorae Parodi accessions
Camila Aparecida de Oliveira dos Reis, Maria Teresa Schifino-Wittmann and Miguel Dall‘Agnol
Abstract: Chromosome number, meiotic behavior and pollen viability were evaluated in a collection of 53 Paspalum nicorae Parodi accessions, which are part of a breeding project of the species. All accessions are tetraploid, with 2n=4x=40. Despite the invariable chromosome numbers, there was variation among accessions in the frequencies of different chromosome configurations at diakinesis and metaphase I, such as univalents, trivalents and quadrivalents. Other abnormalities as bridges and laggards were also observed at anaphase and telophase I. Meiotic indexes ranged from 82.00 to 99.50% and pollen viability from 88.99 to 95.06%. As the species is pseudogamous apomictic, fertile pollen is necessary for endosperm formation. Results show that all plants are meiotically stable and have enough fertile pollen to be used as male parents in controlled crosses.