Comparison of methods of an artificial infection of sunflower seeds by Phoma rot pathogen in the laboratory in soil.

The different methods and application rates of an inoculum powder of sunflower Phoma rot pathogen Plenodomus lindquistii Gruyter, Aveskamp & Verkley for an artificial infection of seeds in the laboratory in soil were studied, the results are presented. The following methods of application of Phoma inoculum powder into soil were studied: into row, mixtures with soil, and on the bottom of a growth tray covered with a filter paper under soil. The application rates of an inoculum powder were 2.5 and 5.0 g per a row of 11 cm length; 5.0 and 10.0 g per 600 g of soil – mixing with soil and on the bottom of the growth tray. The method of application of the inoculum powder into a row in a rate of 5.0 g when the most seeds perished before sprouting were considered to be an optimal one. The sunflower infection with Phoma rot pathogen was weak in variants where pathogen powder was mixed with soil or placed under soil on the bottom of the growth tray. [ABSTRACT FROM AUTHOR]