We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Homeotic sexual translocations and the origin of maize (Zea mays, Poaceae): a new look at an old problem
- Authors
Iltis, Hugh H.
- Abstract
In the Origin of Maize Controversy, the Orthodox Teosinte Hypothesis(OTH; Beadle 1939, 1972; Iltis 1971), five key mutations change 2-ranked (distichous) ears of teosinte (wild Zea) with a single row of grains per rank to 4- to many-ranked (polystichous) maize ears with a double row of grains per rank. BUT teosinte ears are lateral to the I deg. branch axes, maize ears, like their male homologues, the teosinte I deg. branch tassel spikes, terminal, an enigma long unrecognized,hence ignored. In the Catastrophic Sexual Transmutation Theory (CSTT; Iltis 1983b, 1987), now abandoned, the I deg. branch tassel (male) of teosinte (spikelets soft-glumed, paired, i.e., double-rowed per rank, as in maize ears), when brought under female hormonal control by branch condensation, becomes feminized into a maize proto-ear. BUT lateral ears should then have remained teosintoid (2-ranked, each rank with a single row of grains), yet are in fact double-rowed. CombiningOTH and CSTT the new Sexual Translocation Theory (STLT) is based on:first, the branching pattern of teosinte ear clusters (Camara-H. & Gambino 1990), sequentially maturing, sympodially branching, typicallyAndropogonoid systems, called rhipidia (sing. rhipidium), where eachhigher order (younger) ear originates as a lateral branch of its lower order, earlier maturing predecessor; and second, on 3 or 4 key mutations [cupule reduction, softening of glumes, doubling of female spikelets], which, by projecting outward the grains, invited human domestication by making them accessible. Within each ear cluster, the earliest maturing, hence nutrient-monopolizing and largest ear would be selected, all younger ears, already nutrient-inhibited, suppressed. Asfewer, larger ears evolved, and branch internode condensation moved male tassels into female hormonal zones, homeotic conversions translocated female morphology to terminal male positions: first replacing each of the II deg. branch tassels, and ultimately the I deg. branch tassel (
- Subjects
BOTANY; CORN; HORTICULTURE; TAXONOMY
- Publication
Economic Botany, 2000, Vol 54, Issue 1, p7
- ISSN
0013-0001
- Publication type
Article
- DOI
10.1007/BF02866598