igoS] SCHREINER dr= REED-TOXIC PLANT CONSTITUENTS 85 



iiiR a distinct vellow color after a few days. The cultures of wheat 

 seedlings indicated that phloroglucin possesses about the same rela- 

 tive toxicity as p}T0catechin and hydrochinone. True and Huxkel 

 ('98) reported that for lupines phloroglucin was somewhat less toxic 

 than cither of the two diox\^benzenes mentioned. 



In order to study the relative toxicity of phenols containing 



I. 2 



7 



and 3 hydroxyl groups, a series of cultures was set up in which solu- 

 tions of phenol, resorcin, and phloroglucin were employed. It 



- ^' ^ ■^.^\,^^\ - ^r^'. ^- >t ^iW:^t 



Fig. 4 



seemed best to use resorcin and phloroglucin for two reasons. First, 

 they appear to be more stable in solution; and second, because of the 



arransrement 



The 



the 1:3, and phloroglucin the 1:3:5 arrangement. 

 were grown under the same conditions for eight days and records of 

 ^ . . . , i.i-_,-™i, tl^e transpiration is 



Table I shows the 



transpiration 



xperiment, 



records for the growth of the plants in the different solutioi^_, and 

 fig. 4 sho.vs the plants grown in two series of paraUe concen™. 



It would appear from these figures that the toxicity of phenok b 

 not directly dependent upon the number of hydroxj^ gro^ *ey 

 contain. Resorcin appears to be the least toxic of the h^ com 

 pounds and phenol the most toxic. Tkue and Hcxkel tound that 



