Brown rust damage of the winter wheat varieties with different levels of resistance to the pathogen in the south of the Rostov region

Abstract

The purpose of the current work was to study the winter wheat varieties artificially infected with the North Caucasian population of brown rust to identify a damage degree. The study was carried out in two stages on two sets (8 and 10) of varieties with different level of resistance to the pathogen. The trials have established a high damage degree of rust on susceptible varieties, which resulted in productivity decrease from 16.3 to 32.2%. Among the varieties with the maximum damage degree, there was identified the most resistant variety ‘Tarasovskaya 29’ which, when completely (100%) damaged by the disease, showed a minimum productivity decrease, no more than 10.6%. The varieties being poorly susceptible to brown leaf rust reduced the productivity from 11.2% to 20.7%. The smaller indices of productivity decrease among this group were shown by the variety ‘Spartak’. Among the five varieties that showed moderate leaf rust damage, there were different degrees of productivity decrease. The variety ‘Donskaya Yubileynaya’ artificially infected with brown rust, showed a minimal productivity decrease and its structural elements, and it could be identified as the leaf rust resistant variety like the variety ‘Tarasovskaya 29’. When predicting the brown leaf rust epiphytoty, the susceptible and half-resistant wheat varieties require obligatory protection with fungicides.

Keywords

• brown leaf rust
• varieties
• damage
• infectious background
• productivity decrease
• hardiness/resistance