Seasonal variations in adaptational strategies of Beta vulgaris L. plants in response to ambient air pollution: Biomass allocation, yield and nutritional quality

Seasonal variations and effects of ambient air pollutants on palak (Beta vulgaris L. var. Allgreen) plants were investigated with respect to root, shoot length, number of leaves plant-1, leaf area and root and shoot biomass at a suburban site situated in dry tropical area of India, experiencing elevated levels of ambient air pollutants. Air monitoring data showed that mean concentrations of SO2 and NO2 were higher during winter, whereas O3 was the major air pollutant during summer. Plants grown in non filtered chambers showed stunted growth, reductions in biomass and yield and modification in biomass allocation pattern as compared to those grown in charcoal filtered air. Magnitudes of changes in various parameters were more in summer than winter season. Nutritional quality of palak was also negatively affected in non filtered chambers during winter but there was no significant change in nutritional quality during summer season. Biomass allocation pattern revealed that during summer photosynthate allocation to roots reduced with consequent increment in leaf weight ratio, which helped in sustaining nutritional quality of palak even after more yield reductions in NFCs as compared to FCs. This study depicts the variations in adaptational strategies of palak in two different seasons.