Chlorine ions effect on the content of photosynthetic pigments in seedlings of common oats and white mustard

Introduction. Chlorine is one of the essential trace elements. The role of pigments in plant resistance to salinization is currently insufficiently studied. Some authors cite data on a pigments amount decrease during salinization, others have identified an increase or absence of significant changes in the pigment apparatus. The purpose of this research is to determine the chlorine ions influence on the amount of photosynthetic pigments in seedlings of common oats and white mustard. Materials and methods. The research was carried out on the terri-tory of the urban district “City of Yoshkar-Olaˮ. Three functional zones were identified: recreational, residential and southern industrial. Soil samples were taken in the urban soils of the roadside and on the lawns of the studied streets, and the mount of chlorine ions was analyzed by the argentometric method. The amount of photosynthetic pigments was determined spectrophotometrically. Common oats and white mustard were selected as test objects. Research results and their discussion. The research results revealed that the content of chlorine ions in the urban soils of the residential zone was 0.024 %, recreational – 0.017 %, southern industrial – 0.014 %. According to the soils classification by the degree of salinity, all the studied urban soils belong to the non-saline category.A small amount of pigments was found in common oats and white mustard, regardless of the zone. In the seed-lings of the studied plants growing in the soils of the residential and recreational zones, the content of chlorophyll a, chlorophyll b, and carotenoids was higher than in the southern industrial zone. Conclusion. The amount of chlorine ions in urban soils at the level of 0.017−0.024 % promoted an increase in the content of chlorophyll a and carotenoids in seedlings of common oats and white mustard.