Ear-type selection and yield of dent corn
1922
Kiesselbach, T.A.
A review of the available data indicates that, within reasonable limits at least, variations in ear characters are rather neutral in their effect upon the yield of dent corn, except when they are definitely linked with special adaptive growth characteristics of the plant. Thus, slender ears with smooth, shallow kernels tend to be produced on earlier maturing, smaller, and less rank growing plants than are large, rough, deep-kerneled ears of the same variety. In the States of Kansas, Nebraska, Ohio, and Illinois, where the tendency has been to grow too large and late maturing corn types, selection of the rather long, slender, medium smooth ears, with kernels of medium depth and medium shelling percentage, results in somewhat increased production. Ear and kernel characters, aside from those known to indicate soundness and special adaptation, have little significance as indicators of high producing seed ears. There are indications that close type selection, if long continued, may even reduce productivity, thru an approach toward gametic purity for the selected characters. This may also account in part for increased yields sometimes obtained from F1 variety hybrids. Many institutions and individuals have practiced continued type selection in order to achieve uniformity and have perhaps unwittingly introduced an element of close breeding. It has recently been proposed that the root, stalk, and ear rot diseases are somewhat associated with dull and starchy kernels and with discolored or shredded shank attachment. Further and more general investigations may disclose the full significance of ear characteristics as disease indicators. The proposed control of these corn diseases opens a new and important field for investigation.
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