Single Alien Chromosome Additions from Shallot (Allium cepa L. Aggregatum group) Increase Endogenous Polyphenol Contents in Japanese Bunching Onion

Abstract

Eight members of the Allium fistulosum L. – shallot (Allium cepa L. Aggregatum group) monosomic addition line (2n = 17, FF + 1A–FF + 8A) proved to be very effective in revealing the effects of single alien chromosomes from A. cepa on the production of polyphenol in the green leaf tissues of A. fistulosum. The determination of polyphenol content in the green leaf tissue of these monosomic additions was carried out monthly from January 2002 to December 2003. Throughout the 2-year period, every monosomic addition accumulated polyphenols in green leaf tissues. Two-way ANOVA revealed significant differences, at the 1% level, in the polyphenol contents of the various monosomic addition types as well as in various months. Dunnett’s test showed that four monosomic additions (FF + 2A, FF + 5A, FF + 6A, and FF + 8A) caused a greater increase in the amount of polyphenol content than did A. fistulosum. The levels of polyphenol accumulation in the remaining four monosomic additions and A. fistulosum were almost the same. A phenylalanine ammonialyase gene of shallot was allocated to chromosome 2A using two sets of the monosomic additions. These results indicate that the genes related to polyphenol production may be located on the 2A, 5A, 6A, and 8A chromosomes of shallot.