Effect of Diallate and Triallate on Wild Oat and Wheat Cells

Abstract

After 3 days or more germination in 5-(2,3-dichloroallyl) diisopropylthiocarbamate (diallate) or S-(2,3,3-trichloroallyl)diisopropylthiocarbamate (triallate) vapor, shoots and roots of wild oat (Avena fatua L.) and spring wheat (Triticum aestivum L.) were measured, sectioned, stained, and squashed for comparison of growth and mitotic activity. Shoot tissue of wild oat was damaged more readily than root tissue by diallate vapor. The meristematic tissue at the base of the first leaf was apparently more vulnerable than stem apex tissue since it exhibited more divisions and a greater number of abnormalities. The effect of triallate was similar but less pronounced. Shoot tissue of wheat also was more sensitive to diallate than root tissue. This was indicated by reduced mitotic activity and by shoot inhibition. Few abnormalities were observed in wheat even at high concentrations. Results were similar with triallate. Root and shoot measurements indicated that wheat was more tolerant to triallate than to diallate. Shoot inhibition occurred in both wild oat and wheat at concentrations that did not affect mitosis. Mitotic damage from the use of either diallate or triallate thus appeared to be of secondary importance, the major effect being on some phase of cell elongation or expansion.