Effect of plant growth-promoting bacteria and undersown crops on the total protein content of spring barley grain grown in organic agriculture

The use of innovative cereal cultivation technology based on the application of plant growth-promoting bacteria together with undersown legume is gaining particular importance, especially in organic cereal cultivation, which is expected to provide raw material with high protein content under changing climate conditions. To address this, a field study was conducted in 2019-2021 to determine the effects of plant growth-promoting rhizobacteria (PGPR) and phosphorus-releasing bacteria applied together with undersown crops on the nitrogen content, total protein and total protein yield of spring barley grown in organic agriculture. Two factors were investigated in the experiment. A: bacterial formulation: control (without bacterial formulation), Arthrobacter agilis). B: undersown crops: control (no undersown crops), red clover, red clover + Italian ryegrass, Italian ryegrass. The nitrogen content was determined in spring barley grain, and subsequently total protein content and total protein yield were calculated. The results substantiate the conclusion that the development of an innovative technology of spring barley cultivation based on the application of PGPR bacteria together with undersown red clover or a mixture of red clover and Italian ryegrass will ensure obtaining grain with high total protein and total protein yield. Such grain meets high quality parameters, and is a valuable raw material for the production of groats and flakes that are functional foods from organic cultivation.