392 



Effect of Salicylic Aldehyde on Plauts [April-July. 



Effect on cowpeas. An experiment with cowpeas was made 

 similar to that with corn seedlings, using the same conc. of salicylic 

 aldehyde and the same nutrient Solution. The plants grew in the 

 Solutions from June i5th to June 28th. One plant was used in each 

 culture. 



The effect of the aldehyde on the cowpea plants was similar to 

 that with wheat and corn. In Fig. 3 (Plate 6) are shown the 

 plants as affected by the aldehyde. From this it is seen that amounts 

 larger than 10 p.p.m. were extremely harmful to the cowpeas. 



In Table 2 are given the green weights of the cowpea plants 

 taken at the end of the experiment. 



TABLE 2 



Effect of salicylic aldehyde on cowpeas in nutrient Solutions 



The figures in Table 2 show that salicylic aldehyde in amounts of 

 IG p.p.m. did not afifect the green weight, which was the same in that 

 culture as in the nutrient Solution that did not contain aldehyde. 

 The culture containing 25 p.p.m. of the aldehyde, however, produced 

 a much smaller plant than the control. The growth was reduced 

 from 100 to 51. Solutions containing 50,^100, and 200 p.p.m. pro- 

 duced very poor plants, which made very little growth and were 

 almost dead when the experiment was discontinued. 



Effect on cabbage. An experiment in nutrient Solution was 

 made to study the effect of the salicylic aldehyde on young cabbage 

 plants. The nutrient Solution was the same as that used with com 

 and cowpeas. The salicylic aldehyde was used in varying quan- 

 tities from 10 to 200 p.p.m. Ten young cabbage seedlings were 

 grown in each culture. The plants grew in the Solution from May 

 25th to June I2th, 19 12. A photograph of the cultures was taken 

 when they had grown 7 days; they are shown in Fig. 4 (Plate 6). 



