DISEASES OF MINOR FRUIT PLANTS 359 



The failure of attacked plants was completed at one stroke, and 

 the indication given by this feature was confirmed in all the 

 cases examined by the finding of the most severely affected 

 sections at or near the base of the stem, and in one or more of the 

 principal roots. 



It seems on the whole most likely that infection had pro- 

 ceeded from the soil, probably, in some cases examined, through 

 wounds made by removing basal shoots. The possibility remains, 

 however, that wounds kept moist by nearness to the soil may have 

 been more susceptible to infection from the pruning knife than 

 those higher up, and it is somewhat easier to conceive of the 

 knife becoming contaminated than the soil in some of the cases 

 noted, where no Solanaceous plants appear to have been grown 

 in recent times. 



Control. 



According to E. F. Smith, it seems probable that the organism 

 is strictly a wound parasite. He has shown that it may be 

 transmitted by insects, and is inclined to attach great importance 

 to the action of nematode worms in opening the way for root 

 infections, regarding their presence as prohibitive of tomato- 

 growing in infected soil. The St. Vincent plants did not show any 

 obvious signs of the presence of nematodes. The further pre- 

 caution on which most dependence must be placed, according to 

 the author quoted, Ues in avoiding even trifling injuries to the 

 roots in transplanting. For this reason, if the seed cannot be 

 germinated in situ, the transfer must be made with great care 

 while the seedlings are still small enough to make the avoidance 

 of injury possible. It is also obvious that infections may be 

 easily made in pruning. A branch may be infested for a part of its 

 circumference while not yet showing signs of wilt, and the cutting 

 of it will smear the knife with large numbers of the causative 

 bacteria. It would be safest to avoid pruning altogether when 

 infected plants are known to be present. 



It should be noted in conclusion, that it is reported from 

 North Carolina and from Sumatra that ground nuts grown on 

 infested soil have proved susceptible to the attacks of Bacterium 

 solanacearum. 



Bubbly Fruit-Rot. 



At the Kingstown Experiment Station, St. Vincent, in 1917, 

 there came under the writer's observation a bacterial rot of 

 tomatoes of a very swift and decisive nature. 



Bacteria which invade injuries, and cause ripe rot of tomato, 

 as of other fleshy fruits, are not at all uncommon, but the one in 

 question was distinguished by its ability to cause very destructive 

 effects in fruit of any age, and of any size from the small "Native " 

 to the large fruits of Earhana. Its outstanding character was the 



