THE WAXY LOCUS IN MAIZE. I. INTRALOCUS RECOMBINATION FREQUENCY ESTIMATES BY POLLEN AND BY CONVENTIONAL ANALYSES

Abstract

THE waxy (wx) locus in maize conditions the type of starch which is synthesized in the triploid endosperm and in the haploid pollen grain. Further, the phenotype of a pollen grain is determined by its own genotype and not by that of the plant which produces the pollen grain (BRINK and MACGILLIVRAY 1924) and (DEMEREC 1924). This makes it possible to use the pollen grain as the unit of observation in genetical investigations on the wx locus. The Wx pollen grains stain blue with an iodine-potassium iodide stain while wx pollen grains stain a reddish-brown color. Since a maize plant produces millions of pollen grains, large populations can be obtained and scored easily, thus markedly enhancing genetic resolution. The investigation of low frequency events is more easily carried out with this system than with any other locus in a higher organism