The production of a new allopolyploid species

Two salt grass species, Spartina maritima (2n = 60) and Spartina alterniflora (2n = 62) produced an interspecific hybrid (2n = 61) that subsequently doubled its chromosome number by nondisjunction to produce the new salt grass species Spartina anglica, an allotetraploid (4n = 122)Two salt grass species, Spartina maritima (2n = 60) and Spartina alterniflora (2n = 62) produced an interspecific hybrid (2n = 61) that subsequently doubled its chromosome number by nondisjunction to produce the new salt grass species Spartina anglica, an allotetraploid (4n = 122)

Spartina Spartina alterniflora maritima \ Meiosis Meiosis l l i V =3?‘ Gametes ‘ I, \L. \-_ Gamete union lnterspecific _ lnterspecific hybrid is infertile hybrid due to nonhomology of chromosomes. l Chromosome doubling by nondisjuction New species: is 51+2n _12\2\ Homologous chromosome 7 Spartina anglica ' s 2" pairing and disjunction. } The new species is fertile l and can reproduce.