120 



Otis F. Curtis 



Influence of solutions oj sugar for one, five, and fourteen days, respectively, 



in an incubator 



In another experiment more fully ripened cuttings were placed in 

 tumblers containing 100 cubic centimeters of solution, and these were 

 set in incubators at the constant temperatures given in table 14. After 

 the treatment the twigs were rinsed and placed in distilled water. 



TABLE 14. 



Influence of Solutions of Cane Sugar at Different Temperatures and 

 FOR Different Lengths of Time 



(Duration of experiment, September 10 to October 30, 1915. 



to the culture) 



Ten cuttings of Ligustrum 



Solution 



Temper- 

 ature 

 (centi- 

 grade) 



Duration 



of 

 treatment 



, Root 

 length 

 per twig 

 (milli- 

 meters) 



Num- 

 ber of 

 twigs 

 rooted 



■Num- 

 ber of 

 twigs 

 dead 



Distilled water 



Cane sugar, 5 per cent 



Distilled water 



Cane sugar, 5 per cent 



Distilled water 



Cane sugar, 5 per cent 



Distilled water 



Cane sugar, 5 per cent. 



30° 

 30° 

 35° 

 35° 

 30° 

 30° 

 30° 

 30° 



24 hours 

 24 hours 

 24 hours 

 24 hours 

 S days 

 5 days 

 14 days 

 14 days 



22.0 

 40.0 

 148.0 

 127.0 

 165.5 

 268.5 

 4.5 

 191.0 



5 

 5 

 8 



10 

 8 



10 

 2 



10 



In each case at 30° C. the twigs in the sugar solutions showed the greater 

 root development — an increase, as compared to the corresponding check 

 in distilled water, of from 62 to 4144 per cent. At 35°, however, the 

 sugar had a slight retarding effect. In each of the checks from two 

 to three twigs died, while all the treated twigs not only lived but also 

 formed roots, with the exception of two twigs in the 24-hours treatment 

 at 30°. The twigs left in the sugar solution for fourteen days showed 

 a very marked swelling at the base extending from 3 to 4 centimeters 

 above the lower end. This swelling was in the cortex region, which 

 showed also deep longitudinal splits. None of the checks exhibited such 

 swellings. A similar but less pronounced swelling was apparent in most 

 of the twigs used in other experiments when they were left in sugar for 

 several days. 



