A Simplified Method for Auxin Extraction

Abstract

When the auxin content of a plant or part of it has to be determnined two ways are open for analysis. (1) The oldest one is the diffusion method. The auxin of the plant material is allowed to diffuse into agar blocks. This method is more suited for determining the free moving auxin and the auxin production of tips and buds than for determining the actual auxin content of the plant. (2) The extraction method was first used by Thimann (1934). He extracted Avena seedlings by crushing them in chloroform and HCl. This procedure was repeated twice. Laibach and Meyer (1935) extracted maize and Helianthus with alcohol. The extract was concentrated and taken up in lanolin. This auxin paste was smeared on one side of intact Avena test plants. In corn plants up to 30 cm. in height no auxin could be found with exception of the coleoptile tips. Boysen Jensen (1937) reported good results with Thimann's method on Phaseolus. He also used ether and acetic acid and dropped the ether extract on agar blocks (micromethod). Van Raalte (1937) extracted auxin from Vicia roots with ether and HCl.