B GENOME-RELATED KARYOTYPIC VARIATION IN CERTAIN BANANAS IN THAILAND

Many of edible bananas (Kluai in Thai) associated with Musa balbisiana are diversified in Southeast Asia, and their genomes vary from diploid to tetraploid.
This research aimed to examine the chromosome number and karyotype of certain local bananas for their classification and crop improvement.
Root tips of 20 banana accessions were collected from the banana germplasm collection at Pak Chong Research Station and Department of Horticulture, Kasetsart University, stained with Feulgen and then observed under light microscope.
The results revealed that the bananas classified as BB group (2n=22) were ‘Tani Dam’, ‘Tani I-san’ and ‘Tani Nuea’. The banana in BBB group (2n=33) was ‘Thepphanom’. The bananas in AAB group (2n=33) were ‘Roi Wi’, ‘Nom Sao’, ‘Sam Duean’ (Phichit), ‘Nam Lek’ (Songkhla) and ‘Nam Phat’. The bananas in ABB group (2n=33), were ‘Namwa Dam’, ‘Namwa Ngoen’, ‘Namwa Ubon’, ‘Namwa Mali Ong’, ‘Namwa Sai Daeng’, ‘Hin’, ‘Namwo’, ‘Nang Phaya’, ‘Hak Muk Khiao’ and ‘Hak Muk Thong’. The banana in ABBB group (2n=44) was ‘Theppharot’. These genomes were varied in chromosome size ranging from 0.83 to 3.79 microns.
The karyotypes in all groups were composed of metacentric and submetacentric chromosomes.
The satellite was found on the first chromosomal pair in all genomic groups, but found on the second chromosomal pair only in ‘Roi Wi’, ‘Nang Phaya’, ‘Hak Muk Khiao’, ‘Hak Muk Thong’. There was no satellite observed in ‘Tani I-san’ and ‘Tani Nuea’. Our results suggested that karyotypic variation is related to B genome.

International Symposium on Tropical and Subtropical Fruits

P. Phengchang, K. Suvittawat, B. Silayoi

chromosome, satellite, ploidy, Kluai, Musa balbisiana

https://doi.org/10.17660/ActaHortic.2014.1024.7