192 Proceedings of Indiana Academy of Science 



disease, caused by Fusarkim lycopersici. The disease was found as 

 early as May 25 in hothouses near Indianapolis and by July 12 it was 

 very destructive. One grower had replaced the soil of his wilt-infested 

 house and another moved his house to avoid using the old wilt-infested 

 soil. While both secured a good crop, yet in both cases scattered cases 

 of wilt occurred. By July 12 wilt was also severe in the market garden 

 field crop and in one field that had been in tomatoes several consecutive 

 seasons there was a fifty per cent incidence of the disease. Wilt was 

 also found destructive in a hothouse at Vincennes on June 28 and there 

 was evidence of spread of the disease to several other houses with in- 

 fected transplants. It is, of course, to be recognized that any means 

 by which soil from a wilt-infested hothouse is carried to a house where 

 none of the disease has occurred may introduce the disease. In ex- 

 perimental fields at Lafayette, wilt was first noted on June 21, and 

 by the middle of July there was a scattered infection involving about 

 two per cent of the stand. The danger of plant-bed soil infestation as 

 a source of this disease was clearly demonstrated by the discovery of 

 two remnant tomato plants affected with wilt in a plant-bed in John- 

 son County on Sept. 16. This further emphasizes the necessity of keep- 

 ing plant-beds free from tomato plants during the summer since wilt- 

 infected plants increase the volume of infective material in the soil. 



The outstanding feature of the wilt situation this year was the 

 abundant and conclusive evidence of the introduction of this disease 

 into canning crop fields with southern-grown transplants, a danger 

 which has been previously pointed out (18). For a considerable num- 

 ber of growers this evidence was obtained at a high cost. It is likely 

 that in several localities southern-grown plants will no longer be ac- 

 ceptable. On June 30, thirteen fields were inspected near Whiteland, 

 in 12 of which Georgia plants had been used. Wilt was already preva- 

 lent among the Georgia plants in every one of the 12 fields and none 

 was noted in the one field planted entirely with home-grown plants. In 

 fact, in fields where both Georgia and home-grown plants had been 

 Ui^ed, the Georgia plants could be located at oVice by the abundant wilt 

 infection. Somewhat similar observations were made near Kokomo on 

 July 2. Wilt was present in 12 out of 21 fields examined and Georgia 

 plants were used in five of these 12 fields, and Louisiana plants in 3. 

 The disease was severe in four of the five fields of Georgia plants. 

 On July 20, wilt was found present in eight out of eleven fields near 

 Greenfield and was severe in five of these fields, all of which contained 

 Georgia plants. And again, in fields containing both home-grown and 

 Georgia plants, the disease was confined to the latter. In a number of 

 fields near Indianapolis containing Louisiana plants there was evidence 

 that about two per cent of the Louisiana transplants had been infected. 

 In the Indianapolis territory, however, there is also considerable soil 

 infestation with the wilt fungus. As a basis for comparison it is of 

 interest that, in four fields near Southport comprising about 60 acres 

 and planted entirely with home-grown plants, no cases of wilt were 

 found on July 13. 



To summarize these field observations, it is worthy of note that 

 wilt was already severe in 26 of the 76 fields examined before July 22 



