1. Phenol reaction.
In a local maize from Barquisimeto (Venezuela) an fn (colorless phenol reaction) was found. Tested with the previous fn (News Letter No. 22:35‑39. 1948) they proved to be alleles.
The phenol reaction is a pericarp character. Nevertheless, the colorless genotype fn gives in the recently formed grain a colored reaction. The expected "colorless" reaction of the fn grains appears in more advanced stages of the kernels. Considering the pericarp as a dead tissue, the above result suggests that the diastase involved in the "colored" reaction is not originated in the pericarp itself, but in another tissue from which it spreads to the pericarp. If so, this diastase, perhaps, would be found in every corn, but in the fn (colorless genotype) there would be an inhibition to its diffusion to the pericarp of the growing kernel. It is generally observed that the pericarp gets a deeper color near the basal region of the embryo.
Dora M. de Zerpa