MONOCLONAL ANTIBODIES IN AGRICULTURAL TESTING: QUANTITATION OF SPECIFIC WHEAT GLIADINS AFFECTED BY SULFUR DEFICIENCY

Proteins correlating with end-use quality in wheat (Triticum aestivum L.) flour samples have been quantitated using a panel of monoclonal antibodies (MCA) with specificities for different gliadins (grain endosperm storage proteins which are soluble in aqueous alcohol). A beta-gliadin specific antibody was found suitable for measuring sulfur-related quality loss in sets of flours from three wheat cultivars grown under varying conditions of sulfur fertilization. Binding of this monoclonal antibody, measured in a competitive enzyme-immunoassay, was highly correlated with flour sulfur and with the extensibility of, and resistance to stretching of doughs prepared from these flour samples. These results demonstrate that monoclonal antibodies may be used to measure levels of specific components which vary as the technological quality of the foodstuff varies. Rapid spot-tests based on the reaction of seed proteins with specific monoclonal antibodies may aid progeny selection in plant breeding programs.Key words: Wheat-grain quality, monoclonal antibody, immunoassay, sulfur deficiency, gliadin