Polyploidy in Monochoria hastata Solms, and M. vaginalis Prest. Grown in Bangladesh

抄録

Two distinct morphological types (types I and II) each of M. hastata and M. vaginalis having a different and stable chromosome number in each type were recorded. The chromosome numbers in these plant types were 2n=28 in M. hastata-type I and 2n=80 in type II and 2n=24 in M. vaginalis-type I and 2n=52 in type II in both RTCs and PMCs. Based on the morphological and cytological observations, a hypothesis has been proposed in which 52 chromosome plants (M. vaginalis-type II) are suggested to be an allotetraploid between 2n=28 and 2n=24 chromosome plants and 2n=80 chromosome plants as an autoallohexaploid between 2n=52 and 2n=28 chromosome plants and that they may be considered as new species.