A probable origin of triploids in Taro [Colocasia esculenta (L.) Schott]

Abstract

Ploidy levels of the seedlings derived by crossing diploid accessions (2n = 28) of wild taro [Colocasia esculenta (L.) Schott] from Bangladesh were analyzed to seek the origin of triploids (2n = 42). Six and two triploids were detected among 1041 hybrids and 354 selfs, respectively, although most hybrid and selfed seedlings were diploid. These results indicate that triploids in taro originated both in hybrid and selfed seedlings of diploids. Isozyme analysis at the Aat-1 of aspartate aminotransferase of the six hybrid triploids revealed that the seed parent was the double genome donor in five, whereas the pollen parent served as the donor in one. Therefore, both seed and pollen parents are able to serve as a double genome donor of the triploids.