Date of this Version
A variety of maize (Zea mays) differing from other known sorts in the texture of its endosperm was described by Collins (1909). The type of endosperm of this variety was designated as “waxy” in contrast with the starchy and sweet types of other maize. It has since been shown by Weatherwax (1922) that the carbohydrate of this waxy endosperm is erythrodextrin which can be distinguished from other carbohydrates by its red color reaction with iodine. It has recently been reported by Demerec (1924) and Brink and MacGillivray (1924) that this carbohydrate is also present in the pollen of this Chinese waxy variety. With plants homozygous for endosperm type, these authors found that iodine stains the pollen from starchy and waxy maize blue and reddish, respectively. When the pollen from plants heterozygous for these characters was stained with iodine, nearly equal numbers of blue and reddish pollen grains resulted. They interpreted this as a segregation of the waxy and starchy characters in the pollen grains. Longley (1924) has reported such segregation, also determined by the iodine test, in crosses of Chinese maize with starchy maize, and with annual and perennial teosinte, and in crosses between starchy and glutinous Coix. Similar results had previously been reported by Parnell (1921) for glutinous and starchy varieties of rice and their hybrids.