THE DESTRITTION OF VANILLIN IX THE SOIL BY 

 THE ACTION OF SOIL BACTERIA 



By 



WiLMAM J. Bobbins 

 Assisted by A. E. Elizando 



In an earlier publication (6)* it was concluded that 

 the addition of a given toxic organic compound may 

 pro(hice no harmful effects in one soil and decidedly 

 harmful efTects in another, depending on the presence 

 and action of suitable microorganisms which destroy 

 the toxic compound. In the present paper further evi- 

 dence is offered to justify the application of this con- 

 clusion to a number of soils in which the effect of va- 

 nillin on the growth of higher plants has been tested. 

 Vanillin is an aldehyde which is harmful in water 

 culture at a concentration of 1 part per million (7) to 

 wheat plants, and which has been isolated from un- 

 productive soil (8). The writer has shown (6) that in 

 certain Alabama soils it is rapidly destroyed by the 

 action of bacteria. 



The Presence of Vanillin-Destroying Bacteria in 

 Soils Other Than Alabama Soils 



Four investigations in addition to the one carried 

 on at the Alabama Experiment Station (5) have been 

 made on the effect of the addition of vanillin to the 

 soil on the growth of plants. Davidson (2) w^orking at 

 the New York State College of Agriculture found that 

 vanillin had little bad effect on the growth of wheat. 

 Skinner (9) in field tests at the experiment farm of the 

 Agricultural Department at Arlington, Virginia, found 

 that vanillin stunted the growth of cow peas, garden 

 peas and string beans. He found vanillin present in 

 the soil of these plots six months after its application. 

 The same investigator in pot experiments found va- 

 nillin to be harmful to wheat plants grown in infertile 

 Florida sandy loam but to have no effect in fertile 

 Hagerstown loam. Fraps (4) at College Station, Tex- 

 as, found in general little harmful effects from the 

 application of vanillin to potted soil. He also foiand 

 that the vanillin rapidly disappeared during the course 

 of the experiment. Epson and Powell (10) at Lincoln, 

 Nebraska, report that vanillin shows very little 



(* Reference is made by number to Literature cited p.) 



