PLATE VI 
Phytophtkora infestans: Infection of potato shoots and plantlets 
Fig. i.—This shoot grew from a diseased tuber planted in the greenhouse under 
field conditions. Note the discoloration typical of P . infestans running up the stem. 
Fig. 2.—This shoot, which had not reached the surface of the soil, grew from an 
infected tuber in the field. 
Fig. 3.—This plantlet was the progeny of a diseased tuber planted in the open. 
It should be compared with the shoot shown in Plate VI, fig. 1, produced in the green¬ 
house. The same symptoms developed in the field as obtained in the laboratory. 
