Influence of biologization and chemicalization factors on the phytosanitary state of barley in the forest-steppe of Western Siberia

Abstract

The research was carried out to study the influence of biologization and chemicalization factors on the phytosanitary state of barley in the chain of the six-field fodder crop rotation of the second rotation in the forest-steppe of Western Siberia. The biologization factor was considered sowing peas to barley. The chemicalization factor was considered as the introduction of mineral fertilizers according to the results of agrochemical analysis at a dose of N60P20. It was found that the highest development of root rot was found in the variant with sowing barley without fertilizers, where the disease development index reached an average of 14.4% for the plant. The lowest one is in the variant “barley + peas + fertilizers’ (4.6%). In the variants “barley + peas’ and “barley + fertilizer”, the intensity of the disease was approximately the same and within the limits of the severity threshold – from 6.6 to 6.9 %. Similar data were obtained for the prevalence of the disease. Among the analyzed organs, the primary roots had the greatest damage, which was due to significant infection with Bipolaris sorokiniana Sacc. Damage by leaf-stem infections was almost 2 times lower in the variant with the use of the legume component and the application of fertilizers (16.8%) versus the control variant (31.8%). It was found that the correlation coefficient of the root rot development index on average for a plant with productive tillering was r = –0.63, and with plant height r = –0.99. Confirmation of the harmfulness of root rot is a close negative correlation between the yield and the indicators of the development of the disease on average for the plant: r = –0.74. It was found that the most favorable phytosanitary situation developed in the variant of sowing barley with the use of fertilizers and a legume component, which is associated with the healing effect of fertilizers and legumes, which is reflected, on the one hand, in increasing the endurance of the plant itself, and on the other, in an inhibitory effect on causative agents of the disease.