ARS | Publication request: A COMPARISON OF INOCULATION TECHNIQUES FOR ASPERGILLUS FLAVUS ON CORN

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: October 23, 2002
Publication Date: February 1, 2003
Citation: Windham, G.L., Williams, W.P., Buckley, P.M., Abbas, H.K., Hawkins, L.K. 2003. A comparison of inoculation techniques for Aspergillus flavus on corn [abstract]. Proceedings 2nd Fungal Genomics, 3rd Fumonisin Elimination and 15th Aflatoxin Elimination Workshop. p. 139.

Technical Abstract: Field studies were conducted at Starkville and Stoneville, MS, to compare conventional Aspergillus flavus inoculation techniques with granular application techniques. Conventional inoculation techniques included injecting spores under husks using the side-needle technique or spraying spores on ears weekly for 5 weeks with a Solo backpack sprayer. The granular inoculations consisted of broadcasting A. flavus infected wheat in field plots. Granular applications were made 2 weeks prior to midsilk, at midsilk, or 2 weeks after midsilk. Six commercial corn hybrids were included in the tests. Inoculation treatments and hybrids were arranged as a split plot. Inoculation treatments were assigned to main plots and hybrids were assigned to subplots. In Stoneville, aflatoxin levels and A. flavus kernel infection were highest in plots inoculated with the side-needle technique. In Starkville, plots inoculated with the side-needle technique and wheat prior to midsilk had the highest levels of aflatoxin. In a late planted study in Starkville, aflatoxin levels were highest in plots inoculated using the side-needle technique. Plots sprayed with A. flavus and inoculated with wheat prior to midsilk had similar levels of aflatoxin contamination. The commercial hybrid Terral TV2100 had the highest levels of aflatoxin contamination and A. flavus kernel infection in all tests. The commercial hybrid Asgrow RX938 had the lowest levels of aflatoxin contamination and A. flavus kernel infection in all tests. The side-needle technique appeared to be superior to all other inoculation techniques used in these studies. However, in large scale tests where inoculation of individual ears by hand is impractical, the spray technique and application of A. flavus infected wheat prior to midsilk may be useful tools in evaluating corn for aflatoxin resistance. Further studies are planned to improve the efficacy of granular applications of A. flavus.