Genetic analysis of hybrids between maize and perennial teosinte. I. Morphological traits

Eleven Hawaiian tropical maize (Zen mays L.) inbreds (Hi25...Hi35) were crossed with Zea diploperennis, Iltis, Doebley, and Guzman their F1 hybrids and advanced generations (F2 and backcrosses to the two parents) were evaluated in three seasons, and results were studied using generation mean analysis. The F1 hybrid was intermediate in tillering, showed very high hybrid vigor for vegetative growth and possesses ear characters which were intermediate. nle F2 generation showed transgressive segregation for most of the traits studied. Traits that were specific to Zea diploperennis such as tillering and perennialism did not segregate normally in the F2 with a skewedness towards the maize-type. A total of six morphological traits were studied for their gene fiction and presented in this paper. Information on other traits including ear traits are presented in the accompanying paper. AU the characters were greatly influenced by epistatic effects. Additive gene action was the major contributor to inheritance of plant height and tassel length, whereas dominance gene action was more important for leaf length and leaf width. A significant negative dominance gene action nias observed for number of tillers. Traits that were inherited from the maize parent showed high heritability whereas those that were inherited from diploperennis were probably influenced by linkage and some form of gamete selection. The absence of rhizomes in the Fl as weil as in F2 segregants contributed to the absence of perennialism in the progenies. Results from tills study shows promise for using Zen diploperennis as a potential wild relative that could help in improving cultivated maize for forage use. Other traits that would be beneficial are prolificity of ears, and resistance to certain biotic and abiotic stresses.