MAIZE-SILK MAYSIN DATA - COMPARISON OF INTERPRETATIONS OF QUANTIFICATIONS BY SPECTROPHOTOMETRY AND HPLC

Maysin in maize silks is antibiotic to the corn earworm. Our objective was to compare spectrophotometric and reversed-phase HPLC methods of quantifying maysin concentrations. HPLC assay has eliminated abnormally high readings obtained when the spectrophotometric method was used. Maysin of three maize populations, and parents and related generations of two hybrids, was analyzed by both methods and compared. Spectrophotometrically analyzed maysin concentrations of individual silks were similar, but variances differed from those analyzed by HPLC. Spectrophotometric values were scattered for SC235xF44 and its related populations in 1983, but 1988 HPLC determinations produced interpretable data. Data from F6xF44 populations in 1983 suggested that F6 has a gene for reducing maysin content, but 1988 HPLC distributions indicated that the gene in F6 is dominant for low maysin content. The changes in interpretation illustrate the importance of using an accurate method for measuring silk maysin concentration.