VIEW ARTICLE

Methods of Evaluating Stalk Quality in Corn. F. D. Cloninger, Graduate Assistant, ARS, USDA, University of Missouri, Columbia, 65201; M. S. Zuber(2), O. H. Calvert(3), and P. J. Loesch, Jr.(4). (2)(3)(4)Research Agronomist, Crops Research Division, ARS, USDA, Associate Professor of Plant Pathology, Research Geneticist, Crops Research Division, respectively, ARS, USDA, University of Missouri, Columbia, 65201. Phytopathology 60:295-300. Accepted for publication 9 September 1969. DOI: 10.1094/Phyto-60-295.

Both the rind and pith contribute to stalk quality in corn (Zea mays). Thicker rinds and heavier wt of 5.1-cm sections, with and without pith, were found after inoculation with Diplodia maydis. Crushing strength, rind thickness and wt of 5.1-cm sections together gave the best estimate of stalk quality among the 15 possible single crosses of six inbred lines of known resistance or susceptibility to stalk lodging. All methods evaluated provided valid estimates of stalk quality. Diplodia maydis ratings have limitations because some hybrids may suffer considerable stalk rot but still retain satisfactory crushing strength. Inoculations lowered crushing strength except for single crosses involving the stalk-lodging resistant parent B14. Pith condition rating at 12 days after 50% silking gave valid estimates of stalk quality except for the first internode.