The classification of segregants from perennial teosinte x maize hybrids for the perennial trait is difficult. Plants which are scored as annual because they appear to be dead may rest in a dormant state for a month or more and then suddenly a basal or underground shoot will emerge showing that they should have been scored as perennial. Under inadequate light intensity and stunting, this second growth will be abnormal and result in only female spikes as is also the case for stunted corn.
On a basis of scoring for evergreen stalks and its apparent association with basal shoot development, Galinat (1980) thought that perennialism is at least partially controlled by two dominant complementary genes giving a 9:7 F2 segregation ratio. Meanwhile, scoring of an F2 segregation by Mangelsdorf et al. (1981) indicates that trait is recessive.
One important factor that differs in the various studies of perennialism is the corn background. The corn background could be responsible for a reversal of dominance in expression of perennialism.
Walton C. Galinat
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