Effects of freezing on HCN potential of sorghum plants

Hydrocyanic acid is one of the most toxic and rapidly acting poisons found in nature (14). Dhurrin, a precursor of hydrocyanic acid is found in all species and varieties of the genus Sorghum (10). Sorghums are tolerant to drought and have become an important summer crop in the United States (17). In 1963, there were 3,797,000 acres grown for forage and silage (29). In Tennessee in 1962, sorghums grown for forage and silage amounted to 23,000 acres (30). With the advent of the more productive sorghum x Sudangrass hybrids, this acre age is expected to increase (13). Under certain conditions, the hydrocyanic acid content of sorghum plants may become high enough to be lethal to livestock (19). It is generally accepted that actively growing sorghum plants are unsafe for animal consumption after being frozen. The objective of this study was to determine the effect of freezing on hydrocyanic acid potential of Sudangrass and sorghum x Sudangrass hybrids.