Specificity of Pyridinemonocarboxylates and Benzoic Acid Analogues as Chemical Hybridizing Agents in Wheat

A series of substituted pyridinemonocarboxylates and benzoic acids were evaluated in growth chambers as potential chemical hybridizing agents for wheat (Triticum aestivum L.). Chemical hybridizing potential, measured as spike sterility, was observed with both areas of chemistry. The 3-pyridinecarboxylic acid, 4-hydroxy-2, 6-bis(trifluoromethyl) methyl ester, and 2,4-bis(trifluoromethyl)benzoic acid were the only molecules to exhibit complete spike sterility. Minor changes in both molecules resulted in total loss of activity. Substitutions at the 4-position on the pyridinemonocarboxylate which are subject to hydrolysis to the 4-hydroxyl or which contained an acidic proton functionality were the only substitutions exhibiting any level of spike sterility.