Effect of Benzimidazole on Detached Wheat Leaves

Abstract

DETACHED wheat leaves when floated on water retain their green colour for a few days only and are usually chlorotic within a week. During a study of the effects of analogues of nucleic acid components on detached wheat leaves we noticed that those that floated on 30–100 p.p.m. of benzimidazole retained their green colour and their capacity to support growth of leaf and stem rusts of wheat for periods up to at least one month. Other compounds reported to be analogues of essential purines and pyrimidines (barbituric acid, 2-amino-4-methyl pyrimidine, 2,6-diamino purine sulphate, thiouracil, 2-chloro-4-methyl benzoic acid at 1–1,000 p.p.m. or azaguanine and azaadenine at 50–100 p.p.m.) did not give this effect. Similarly, there was no effect with the purines, adenine and guanine, and the pyrimidines, thymine, cytosine and uracil at 50–200 p.p.m.