Determination of some physiological parameters in spinach (Spinacia oleracea L.) cultivated in Kosovo

The objective of this work was to investigate the levels of photosynthetic pigments, antioxidant enzyme activities (superoxide dismutase [SOD], catalase [CAT], peroxidase [POX], ascorbate peroxidase [APX], glutathione reductase [GR], and MDA), total glutathione (GSH), total ascorbate (AsA), and lipid peroxidation of two spinach cultivars (Clipper and Matador) sampled in different locations in Kosovo (Prizren, Ferizaj, and Obiliq). The photosynthetic pigments, chlorophyll a and b as well as carotenoids, were extracted by 80% acetone, and concentrations were calculated based on the absorbance values at 663, 645, and 480 nm. There was a significant difference in SOD, APX, and GR activities between varieties at each location. The MDA and AsA contents in Obiliq were the highest, compared to other locations. From the increase in lipid peroxidation level, it can be assumed that the degradation in pigment content was caused by the decrease in total AsA content and APX and GR enzyme activities, which are the main enzymes of the AsA–GSH cycle in chloroplasts.