Pollen fertility and karyotyping study of Terminalia catappa and Terminalia mantaly

Abstract

The present study investigates pollen fertility, chromosomes number and karyomorphology of T. catappa and T. mantaly collected from Humid Forest Research Station, Umuahia Nigeria. The study was cytologically carried out using acto-orcein for pollen fertility percentage and somatic chromosome determination. The aim was to compare the pollen fertility and karyotypes of the two species. Pollen fertility was based on stainability test. The pollen fertility percentage mean obtained in T. catappa was 87.30 %, in T. mantaly, the pollen fertility percentage mean obtained was 73.80 %. Somatic chromosome number determined for the two species was 2n = 24, haploid chromosome number was n = 12. In karyotype analysis, chromosome length was between 3.18 to 3.26 μm. Two types of chromosome centromere were observed; metacentric (m) and sub-metacentric (sm) with the karyotype formula 5m+7sm in T. catappa and 9m+3sm in T. mantaly. This study has highlighted the differences in pollen fertility and karyomorpology of the two species investigated. Findings from this study can be applied in plant breeding and conservation programme.