Occurrence and inheritance of 2n pollen in Musa

Sexual polyploidization explains the formation of most polyploid crop species and provides means for their genetic improvement. This paper reports the occurrence and inheritance of 2n pollen in diploid and polyploid Musa. Pollen samples of male fertile accessions available in the field gene bank of the International Institute of Tropical Agriculture were microscopically examined throughout a calendar year. Based on pollen diameter 2n pollen producers were identified. The presence of 2n pollen in diploid species suggests that unilateral sexual polyploidization (2n x n) could have been involved in the origin of triploid Musa species. Segregation data suggests that at least one dominant gene controls 2n pollen production in Musa. Further introgression of desirable alleles from diploid species to polyploids could be achieved either through unilateral or bilateral (2n x 2n) sexual polyploidization in Musa. (C) 1997 Annals of Botany Company.