Grasses, cyanide

Finding (Blue Grass) EH-4. Cyanide was present in the alkaline hydrolysate from all the energetic materials tested at HAAP. If the hydrolysate is neutralized or made acidic, HCN will be liberated. 

Grossmann K, Kwiatkowski J, Evidence for a causative role of cyanide, derived from ethylene biosynthesis, in the herbicidal mode of action of quinclorac in barnyard grass, Pestic Biochem Physiol 51 150-160, 1995. 

Cyanide in trace amounts is found in a large number of plants, mainly in the form of substituted glycosides. Affected plants include grasses, fruit kernels, pulses, linseed and cassava. 

The Romans used cyanide from natural seed sources, such as apple seeds, for executions and suicides. The seeds of apples, apricots, cherries, peaches, plums, and some other fruits contain sources of cyanide. Other natural sources of cyanide include arrowgrass, sorghum, flax, velvet grass, and white clover. 

Auxin Herbicide Action in Grasses The Role of Cyanide... 

The accumulated ACC appears to be transported to the shoot, where it induces more synthesis of ACC which is converted to ethylene and cyanide. Treatment of isolated shoots with ACC via the vascular system stimulated ACC synthase activity and ethylene and cyanide production [7,37,49,51]. Cyanide was formed as a coproduct of ethylene in the oxidation of ACC, catalyzed by ACC oxidase [14,52]. While quinclorac-induced increases of ABA and hydrogen peroxide are not enough to elicit herbicidal effects [7], cyanide levels in the grass shoot tissue accumulated according to the herbicide concentration and application time and closely correlated with phytotoxicity... 

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