Indiana Plant Diseases. 195 
infection caused barrenness. Rust was of general occurrence. One plant 
affected with the leaf-spot caused by Physoderma zeac-maydis was found at 
Shelbyville by J. F. Trost. Severe hail injury occurred in many sections. 
COWPEA. 
Leaf-spot due probably to Phyllosticta phaseolina was found very abun- 
dant both on leaves and pods in a field near Decker August 19. This dis- 
ease was noted at Vallonia in 1919. 
CUCU MBER. 
By far the most serious disease was bacterial wilt due to Bacillus trach- 
eiphilus. This disease was noted in greenhouses and market gardens, and 
in the pickle crop about Plymouth wilt was far worse than previcusly 
recorded and continued its attack well into the season. Where the single- 
plant-to-the-hill system of culture was used, wilt caused many unproduc- 
tive blank spaces in the fields, and row planting would have been preferable 
to hill planting this season. 
ig. 6. Cucumber mosaic. 
Mosaic (Fig. 6) was not prevalent in greenhouses but in the pickle crop 
was very destructive and ranked next to wilt in importance. It was found 
in 12 out of 15 fields examined near Plymouth, August 31, but in general 
the attack seemed to be of recent inception. The outstanding symptom was 
the yellowing rather than the mottling of the foliage. 
Anthracnose due to Colletotrichum. lagenarium was destructive in the 
Same greenhouses where it occurred last year and was again associated witli 
the practice of overhead watering. No fruit infection has been noted. 
Angular leaf-spot caused by Bacterium lachrymans was found in cold- 
frame cucumhers and to a slight extent in the pickle crop about Plymouth. 
Seed disinfection for this disease is now practiced by the Heinz company 
and their crop is relatively free from infection. 
