METHOD FOR UNIFORM INFECTION OF SEEDLING AND ADULT CEREAL PLANTS BY PUCCINIA-GRAMINIS F SP TRITICI

An inoculation chamber was constructed to inoculate seedling and adult plants of cereals uniformly with urediospores. Plants were rotated in 1 direction while revolving in the opposite direction in a cloud of spores of known concentration. Comparison of 3 liquid spore carriers and dry spores showed that an inert fluorochemical, FC-40, was the most satisfactory. Use of the inoculation chamber, the fluorochemical spore carrier, and standardized conditions for plant growth and incubation gave infection rates with standard deviations of 7-16% of the mean for seedlings and 10-36% of the mean for adult plants.