Waxy maize is a special type of cultivated
maize and has grown in China for long history.
However, the evolution and origin of waxy maize still
remain unknown. We analyzed the origin and evolution
of waxy maize by sampling DNA sequences
from four taxa with eight populations: waxy maize
and other maize cultivars from Southwest China or
America (Zea mays L. ssp. mays), parviglumis (Z.
mays L. ssp. parviglumis Iltis et Doebley), three more
distant species within this genus (Z. luxurians (Durieu
et Ascherson) Bird, Zea perennis (Hitchcock) Reeves
et Mangelsdorf, and Zea diploperennis Iltis, Doebley
et Guzman), and a representative of sister genus
(Tripsacum dactyloides L.). We sequenced 20
sequences and downloaded 26 sequences from NCBI
for the glb1 locus, which encodes a nonessential seed
storage protein. Within the Zea genus samples, the
waxy maize has the minimum sequence diversity,
which contains 31.1% of the level of diversity of
parviglumis and 58.5% of the level of diversity of
normal maize from Southwest China. Sequence
variation within glb1 locus is consistent with neutral
evolution in all four taxa according to Tajima’D test.
From the NJ tree for glb1 sequences waxy maize
formed two main groups which are intermixed with
normal maize sequences. These results suggest that
the Chinese waxy maize originate from a single gene
mutation from normal maize. Combined with the
history of maize dispersal in China we can even think
that Chinese waxy maize was divergenced from
Chinese flint maize.