42 BULLETIN 45, HAWAII EXPERIMENT STATION. 
more readily be adopted as a universal practice. At the present time 
some of the growers are taking up spraying and other crop improve- 
ment measures with commendable zeal, and sprayed plats have shown 
increases of from 50 to 200 per cent over unsprayed plats. In con- 
trolling the late blight, a locally developed variety appears to offer 
considerable promise in resisting foliage injury. 
The improvement of the potato crops can be permanently brought 
about only through a realization of the importance of the several 
factors involved in the crop failures, and especially the diseases and 
pests must be prevented. This can be accomplished only through the 
use of good seed, fertile, disease-free soil, and spraying, combined 
with the best cultural methods. 
o 
