VIEW ARTICLE

Techniques

Field Inoculation Techniques to Evaluate Maize for Reaction to Kernel Infection by Aspergillus flavus. S. B. King, Research plant pathologist, USDA, ARS, and Department of Plant Pathology and Weed Science and Department of Agronomy, Mississippi State University, Mississippi State 39762; G. E. Scott, USDA, ARS, and Department of Plant Pathology and Weed Science and Department of Agronomy, Mississippi State University, Mississippi State 39762. Phytopathology 72:782-785. Accepted for publication 21 October 1981. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1982.. DOI: 10.1094/Phyto-72-782.

Four inoculation techniques for evaluating reaction of maize to infection of kernels by Aspergillus flavus were tested in the field on 10 commercial maize hybrids representing a range of kernel hardness. Inoculations were made 20 days after the midsilk stage, and at maturity kernels not wounded during inoculation were surface sterilized and plated to determine the percentage infection. Inoculation by injecting an A. flavus conidial suspension into the silk channel or by atomizing a conidial suspension onto exposed kernels resulted in infection levels too low (≤ 7%) to adequately differentiate among genotypes. Kernel injection and pinbar inoculation techniques, in which kernels near wound-inoculated kernels were assayed, demonstrated significant differences among some hybrids. The pinbar technique was considered best because it resulted in higher levels (9–48%) of kernel infection, was relatively easy to use, and provided a large number of kernels for assay. Kernel hardness was not correlated with reaction to kernel infection.