RESPONSE OF WINTER COMMON WHEAT VARIETIES TO FOLIAR FERTILIZATION

Abstract

In 2021/2022 – 2022/2023, an experiment with two varieties of winter common wheat was conducted at the training and experimental field of the Department of Plant Production at the Technical University - Varna. During their spring vegetation, combined mineraland foliar fertilization were applied. Soil fertilization was carried out with ammonium nitrate with a fertilizer rate of 12 kg/da (active substance) in phase BBCH 23-29. Three fertilizer products were used for foliar fertilization. They were applied twice with a dose of 300 ml/da in phases BBCH 29-39 and BBCH 51-59. An unfertilized control was also included in the experiment for comparative analysis. The response of the studied varieties to the used foliar fertilizers is expressed by the obtained yields and the protein content in the grain. Foliar fertilization under favorable weather conditions increases the productivity and protein content in the grain of the varieties Marilyn and Nikodim. Under these conditions, the effect of the fertilization factor is large. Under unfavorable weather conditions, the share of the variety factor is significant. Under favorable conditions of the year the average yields obtained in the fertilizer variants compared to the unfertilized controls are higher, while for the protein content this dependence is observed in the year with unfavorable conditions. The Nikodim variety shows higher average grain yield values ​​in most fertilization variants, which suggests that this variety may be more reactive to different types of fertilization. The Marilyn variety shows lower variability in the results, which suggests greater resistance, albeit with lower average yields under some types of fertilization, but with higher protein content.