Zea (genus)

Maize ( Zea mays subsp. Mays)

Zea is a genus of grasses, one of the well as a crop of maize ( Zea mays subsp. Mays). The genus includes four to five types and comes with the exception of the world's cultivated maize only in Mexico and Central America before.

Features

The species are strong annual or perennial plants. They grow upright or with a rhizome. The leaves are constantly stalk. The ligule ( ligule ) is membranous. The leaf blades are large, linear and flat.

The inflorescences are unisexual, which can carry a plant male and female inflorescences ( monoecious ). The male inflorescence is a terminal raceme branched spike. The inflorescence axes are slim and have no knots. The male spikelets are in pairs, one sessile, the other being stalked. The glumes are herbaceous and much more annoying, the upper and lower flower are similar and both fertile. Lemma and palea are translucent. Three Lodiculae and three stamens are present per flower.

The female inflorescence is a single ear of corn, which is in the axil of a leaf and is surrounded by one to several leaves. The ears axis may be thickened and usually carries two rows of spikelets. The female spikelets are sessile and are available individually on the inflorescence axis. The lower glume is hard, smooth and winged at the top, the top is membranous. The lower of the two flowers per spikelet is sterile. The lower lemma as well as the lower glume is small and translucent. The top flower is fertile. Lodiculae missing. The ovary bears a single long stylus with a scar. The stylus goes beyond the piston enveloping leaves. In Zea mays subsp. mays, the cultured maize female inflorescence is a massive, thick cock, which carries four to 36 rows of spikelets that are recessed into the flask.

The fruit is a caryopsis.

System

The wild forms of the genus are grouped under the name teosinte and were asked earlier because of differently appearing inflorescences in a separate genus Euchlaena. However, it has been found that the corn is developed from the earlier than Euchlaena mexicana teosinte combined forms, especially from the Zea mays subsp described until 1980. parviglumis and to a lesser extent from Zea mays subsp. mexicana. These sub- species are still present in Mexico and Guatemala.

The GRIN database performs the following species and subspecies:

  • Zea diploperennis
  • Zea perennis
  • Zea luxurians
  • Zea nicaraguensis - perhaps belonging to Z. luxurians
  • Maize (Zea mays) subsp. huehuetenangensis
  • Subsp. mexicana
  • Subsp. parviglumis
  • Subsp. mays, the cultivated maize.

Documents

  • Gerrit Davidse: Zea, in:. Flora Mesoamericana, Volume 6, 1994, online ( accessed February 4, 2008 )
  • Gerrit Davidse: Zea, in: Flora de Nicaragua online ( accessed February 4, 2008 )
de