84 



PROTECTION OF PLANTS — 1923-24 



Eflfect of Duration of Treatment. 



To test the effect of duration of treatment, two, 100 seed samples of the 

 different varieties of seeds were counted out and dipped in a solution of forma- 

 lin, 1 pint to 40 gallons (1 :40), for varying lengths of time. The control samples 

 of seed were dipped in tap water, instead of the formalin solution, for the diffe- 

 rent lengths of time. 



After treatment the seed was drained for ten minutes, covered for one hour, 

 and then allowed to dry before being placed to germinate. The seed was ger- 

 minated on the top of moist sand, in flats kept in the greenhouse, at a tempe- 

 rature of 19-22.5 C. 



In the following table the percentages denote the average of two samples 

 of seed of each variety. 



TABLE II. 

 Eflfect of Duration of Treatment. 



It will be readily observed from Table II that the ordinary duration of 

 treatment is not a factor of primary importance in the germination of the hailed 

 varieties, when the seed is dipped in a solution of formalin of 1 pint to 40 gallons 

 (1:40). There was, however, a decided injury when the seed was treated for 



