Culture Associated Variation in Maize Inbreds

The extent of culture associated variation generated by a brief passage through tissue culture was evaluated in four maize inbred backgrounds: A641, H99, MS7I, and PA91. The progeny resulting from two generations of self-pollination from the original regenerates were evaluated along with appropriate sexual controls in a replicated field experiment. Eighty regenerate lines and twenty controls were evaluated in each background. Data were collected for 22 traits and were subjected to analysis of variance, discriminant analysis, and principal component analysis. In 58 of 88 combinations of background and trait, the contrast of controls vs. regenerates was significant. The culture cycle increased the variation and changed the association between traits. Testcross hybrids involving these regenerate lines and controls were also evaluated with little or no significant variation or differences between regenerate hybrids and controls being detected.