Agronomy and Horticulture Department


Date of this Version



Published in Agronomy Journal (September-October 1993) 85(5): 1,095-1,096.


Spectrophotometry is a useful assay for hydrocyanic acid potential (HCN-p) in sorghum and sudangrass [both Sorghum bicolor (L.) Moench] seedlings, but no systematic study of sources of variation in the procedure has been reported. Selfed seed was harvested from each of 12 ramets (two each from two sister plants from three low-HCN-p sudangrass parents), and seedlings for sampling were grown ina growth chamber, in two rows from each ramet, Seven-day-old seedlings were harvested and divided into two samples per row for extraction; two aliquots per extract were assayed spectrophotometrically for HCN-p. The experiment was replicated three times. The three parents differed in HCN·p. Rows within ramets, and samples within rows, were also significant sources of variation, but the magnitude of variance component estimates was small relative to that of the parents. Sister plants within parents, ramets within plants, and aliquots within samples were not significant sources of variation.