Investigation of the Physiological Effects of Plant Conditioners in Field Experiments of Winter Wheat

Our study aimed at to test the effects of two different plant conditioners on some morphological parameters, yield and grain quality of winter wheat (Babona) in a field experiment with medium plots, and to investigate some physiological parameters closely related to yield quantity and quality at the beginning of ear emergence by in vivo field measurements. At the beginning of ear emergence we determined the relative chlorophyll content of leaves (SPAD value), moreover leaf reflectance was measured with a portable spectroradiometer to produce spectral vegetation indices that can be used to evaluate the effects of treatments on chlorophyll, carotenoid, anthocyanin and water content of leaves, and to infer photochemical efficiency and stress sensitivity. The results were strongly influenced by the unfavourable rainfall distribution during the growing season. Precipitation deficit in spring significantly reduced the development of the crop stand (yield was below the national and county levels), and its effect was also observable in quality parameters (low raw protein and gluten content), but the positive effect of treatment 1 was detectable: higher yield and quality, higher plant height and ear length compared to the control. At the beginning of ear emergence, some spectral vegetation indices indicated the positive effect of treatment 1 despite the drought: chlorophyll content and photochemical activity of leaves were higher, and higher stress sensitivity and protective pigment concentration in the control.