PLOIDY DETERMINATION OF Musa GERMPLASM USING MORPHOLOGICAL DESCRIPTORS
AND CHLOROPLAST COUNT IN PAIRS OF STOMATAL GUARD CELLS
Ukwueze, C.K., Oselebe, H.O. and Nnamani, C.V.
Musa species comprise different ploidy natures with most cultivated species being triploid. This
results in its sterility and limits improvement. This work was aimed at determining the ploidy nature
of Musa accessions from identified Musa germplasm, using cost-effective procedures. Accessions
from Musa germplasm of Ebonyi State University, Abakaliki were assessed. To classify their
genomes, twenty-six morphological descriptors of both qualitative and quantitative traits were
employed. Chloroplast density in pairs of stomatal guard cells of the accessions was also determined.
Morphological description showed that germplasm were variants of banana and plantain with 54.55
% of accessions classified as diploid, while 45.45 % were triploid. The chloroplast count showed
significant difference at p ≤ 0.05 with chloroplast number which ranged from 9 to 18. ‘Efol red’ had
mode and mean of 9 and 9.45 ± 0.61, respectively, while Calcutta 4 and PITA 14 had mode of 16,
with a mean of 16.70 ± 0.92 for PITA 14. The chloroplast count grouped 18.18 % accessions as
tetraploid, 72.73 % as triploid and 9.09 % as diploid. Although morphological characterisation is
ideally the first method to adopt while classifying variants, chloroplast characterisation has brought
better clarity since its influence by the environment is limited.
Key words: Musa species; chloroplast count; accession; germplasm; morphological descriptor