Notes on teosintes
Perhaps the "trick" to getting Huehuetenango to flower readily is to expose it to decreasing daylengths. In January 1982 I planted seed obtained from H. H. Iltis in the winter greenhouse here in Columbia. The plants grew well and became very vegetative, but never flowered. This contrasted with Zea diploperennis, Z. luxurians, Nobogambe, Chalco, and Balsas, all of which were profuse. This tall (18') Huehuetenango was maintained through the summer, in situ, until August when I chopped it down. From a tiller lying on the ground I potted a side-shoot (8") with extended, but not rooted, root primordia. It subsequently started to take off about October and flowered on December 1st. The main tassel shed abundant pollen, but all side-shoot tassels were aborted. As of January 1st it continues to flower, though the plant is clearly beginning to senesce. Good seed set was obtained from selfing and by crossing with maize.
Using seed obtained from H. H. Iltis, the following inter-teosinte crosses are readily made: Zea diploperennis x Z. luxurians, Z. luxurians x Z. diploperennis, and Z. diploperennis by Huehuetenango. Crossing Z. luxurians to several Corn Belt inbreds gave scattered seed, but to Mo20W gave full set.
Z. diploperennis is perennial from the fact that it forms rhizomes. Rhizome-like structures are also formed occasionally at above-ground internodes on potted tillers that are allowed to recline sharply (though not touch the soil), or that have been "topped." Typically, a side shoot is formed from a bud which is aligned with and located below the gap in the nodal ring of root primordia. A second type of structure can differentiate instead, characterized by a basal ring of root primordial buds, enclosing scales and a fleshy, rather than leafy apical structure. When this rhizome-like propagule is broken off and potted, it emerges with the same morphology as do the newly appearing shoots from the main rhizome. Perhaps Z. diploperennis would be a good candidate for regeneration experiments.
Stephen A. Modena
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