

EFFECT OF VANILLIN AS A SOIL CONSTITUENT 



J. J. SKINNER 

 Department of Agriculture, \\ ashing ton ^ D. C. 



INTRODUCTION 



The effect of vanillin on plants in solution cultures, in pot 

 cultures, and in field plots has been the subject of an investiga- 

 tion by the laboratory of Soil Fertility Investigations which was 

 made necessary by the discovery of vanillin in soils. 1 Vanillin 

 has the characteristics of an aldehyde, and exists in the seeds, 

 roots, stem, leaves and grain of many plants. 2 



It is harmful to wheat seedlings in water cultures, even in such 

 low concentrations as a few parts per million, and the plants are 

 killed in solutions of 500 parts per million in a few days. 3 The 

 toxic effect is less marked upon the tops of the wheat plants than 

 upon their roots. Vanillin is also harmful in nutrient culture 

 solutions composed of calcium acid phosphate, sodium nitrate, and 

 potassium sulphate. It is an oxidizable substance and is less 

 harmful in solutions of some of these nutrient salts than in others, 

 especially those high in nitrate. 4 Sodium nitrate and calcium 

 carbonate, 5 which themselves induce oxidation, ameliorate the 

 harmf ulness of vanillin. 



The isolation of vanillin from soils and its harmfulness to 

 plants in aqueous solutions has made a study of its effect in soils 

 and under field conditions essential. The results of such experi- 

 ments with cowpeas, garden peas, and string beans will now be 



1 Shorey, E.C., Jour. Agr. Res., 1: 357, 1914. 



2 See especially Sullivan, M. X., Jour. Ind. Eng. Chem., 6: 909, 1914. 



3 Schreiner, Reed, and Skinner, Bull. 47, Bureau of Soils, U. S. Dept. Agr., 

 1908. 



4 Schreiner and Skinner, Bull. 77, Bureau of Soils, U. S. Dept. Agr., 1911. 

 6 Schreiner and Reed, Am. Chem. Soc, 30: 85, 1908. 



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THE PLANT WORLD, VOL. 18, NO. 12, 1915 



