keys to the vascular plants of east texas - Botanical Research ...

1100 POACEAE/ZEA
which in turn is derived from mahiz, a Haitian word which Columbus adopted for this grain”
(Shosteck 1974). The widely used English common name, CORN, is related to the German Korn,
which may be a corruption of the Latin granum, seed or small kernel (Shosteck 1974). (Greek:
zea or zeia, a kind of grain—Iltis 2003) (subfamily Panicoideae, tribe Andropogoneae)
REFERENCES: Finan 1948; Iltis 1972, 1983, 1987, 2000, 2003; Doebley & Iltis 1980; Iltis & Doebley
1980; Crosswhite 1982; Doebley et al. 1987, 1995; Doebley 1989, 1990, 1996; Gaut & Doebley 1997;
Provan et al. 1999; Benz 2001; Eubanks 2001; Piperno & Flannery 2001; Smith 2001; Matsuoka et
al. 2002; Westerbergh & Doebley 2002; Hancock 2004.
Zea mays L. subsp. mays, (from an aboriginal name), MAIZE, CORN, INDIAN CORN. Large, coarse,
monoecious annual to ca. 4+ meters tall; culms succulent, to 5 cm in diam.; leaves mostly
cauline, 2-ranked; ligule a short membrane; leaf blades very broad (to 10–80 mm wide), flat,
with auricled base; pistillate spikelets sessile, numerous, paired in several rows on a much
thickened, woody-corky axis (= cob), the whole cylindrical inflorescence (= ear) not disarticulating,
covered by modified leaves or bracts (= shucks or husks), each pistillate spikelet with 2
florets, the upper perfect, the lower usually sterile and reduced; styles (= silk) elongated, unbranched,
dangling from the inflorescence; staminate spikelets resembling those of Tr ipsacum,
in pairs on a terminal panicle (= tassle) with spike-like branches, 1 spikelet of each pair with
pedicels 3–6 mm long, the other nearly sessile; pedicelled and sessile spikelets similar, each
with 2 staminate florets. Widely cultivated and occasional as a transitory escape along roads,
disturbed sites, or waste areas; McLennan (BRIT) and Grayson (G. Diggs, pers. obs.) cos., though
not often collected, probably on roadsides in numerous counties where cultivated; throughout
TX; se Canada and throughout most of the U.S. May–Jul, sporadically to Oct. Because artificial
selection by humans has resulted in MAIZE being quite different from any other grass (particularly
in terms of its pistillate inflorescence), there has long been disagreement over its origin.
Based on numerous molecular and morphological studies (see Doebley and/or Iltis references
above), MAIZE is now generally accepted to be derived from a wild Mexican grass, TEOSINTE—Z.
mays L. subsp. parviglumis H.H. Iltis & Doebley (Iltis 2000). Further, MAIZE is fully interfertile
with TEOSINTE, a fact of importance to corn geneticists, and introgression between MAIZE and
TEOSINTE can occur. However, Eubanks (2001) has suggested that Tripsacum may also be involved
in the origin of cultivated MAIZE—successful crosses have been made between Zea diploperennis
H.H. Iltis, Doebley & Guzmán (a diploid, perennial TEOSINTE) and Tripsacum dactyloides, with
some of the resulting progeny having features resembling ancient MAIZE (Eubanks 2001). Nonetheless,
genetic research over the past three decades has “overwhelmingly established … teosinte as
the solitary wild ancestor of maize” (Smith 2001). MAIZE has long been cultivated (first domesticated
about 6,000–9,000 years ago) by Native Americans and was soon widely planted from
North to South America, but it is thought to have originated in Mexico (Mabberley 1987; Doebley
1990; Heiser 1990; Benz 2001; Piperno & Flannery 2001; Matsuoka et al. 2002; Iltis 2003). Recent
molecular evidence (Matsuoka et al. 2002) suggests that all modern MAIZE strains can trace their
origins to a single domestication in southern Mexico. This species was very important in pre-Columbian
Mesoamerica as part of the maize/beans/squash agricultural system. Along with
WHEAT and RICE, MAIZE is one of the three most important food plants for humans worldwide;
while world MAIZE production is nearly as great as that for either WHEAT or RICE, a much higher
percentage of MAIZE is used for animal food (Chrispeels & Sadava 1977). Overall, MAIZE is considered
the “world’s third most important crop plant,” and “No other American grass has such agricultural
importance” (Iltis 2003). MAIZE can also be converted to alcohol, some of which is used as
a substitute for gasoline in motor vehicle fuel (however, such a use is questionable due to the high
energy costs of producing MAIZE). There are various other uses—e.g., the shucks as a covering for
the cooking of tamales. Hundreds of indigenous races exist (particularly in Mexico), and numerous
cultivars have been developed. According to Iltis (2003), “Supersweet cultivars have a double
recessive gene that delays the conversion of sugar to starch; flint corns have unusually hard endosperm;
and waxy cultivars have endosperm with an unusually high level of proteins and oils.