Influence of long-term mineral fertilization on the content of main macronutrients in the aboveground biomass of maize hybrid Kneja-435

Chlorophyll content is directly related to the rate of photosynthesis. Changes in the photosynthesis due to reduced amount of chlorophyll affect the weight and quality of grain. A two-year field trial was carried out (2022-2023, 2023-2024) with 12 varieties and lines of common winter wheat with the aim to determine the relationship of chlorophyll concentration during grain filling with yield and its components. The index of chlorophyll content was determined using Chlorophyll Content Meter Model CCM-200 Plus. The measurements were done at stage grain filling, the accessions being grouped according to their date to heading. Chlorophyll content was most variable in the early heading genotypes. The results were unidirectional over years. During the first vegetative growth season, a significant positive correlation with yield was determined, while during the second vegetative growth season it was negative but low. A low correlation of chlorophyll concentration with test weight and protein content in grain was found. The established significant differences in the chlorophyll concentration between the individual genotypes confirmed the possibility of using this precise tool for differentiation of the lines during the breeding process. The identified genotypes with high chlorophyll content were suitable to use as potential germplasm in the breeding programs.