A comparison of controlled environment and field trials for detection of resistance in cereal cultivars to root rot caused by Rhizoctonia solani

A screening test was developed to study the effect of different quantities of inoculum of Rhizoctonia solani on root rot and growth of cultivars of wheat, barley, oats, rye and triticale in a controlled environment and the field in two seasons. The ranking of relative susceptibility to disease of cultivars within a cereal differed between the controlled environment and field experiments, and between seasons in the field. The ranking of relative susceptibility between cereals also differed between experiments. In the controlled-environment experiment, wheat had the highest disease rating, followed by oats, barley, triticale and rye, but in the field barley had the highest rating followed by wheat and then oats. The overall differences between the cereals were small.