Effect of mineral nutrition on the CO2 assimilation rate, activity of antioxidant enzymes and productivity of winter wheat varieties

Abstract

Aims. To explore peculiarities of response of new high-yielding winter wheat varieties on mineral nutrition deficit by parameters of activities of photosynthetic apparatus and antioxidant enzymes of chloroplast. Methods. In the phase of milk ripeness, the chlorophyll content, the CO₂ exchange rate and activity of chloroplast antioxidant enzymes, superoxide dismutase (SOD) and ascorbate peroxidase (APX), in flag leaves of winter wheat varieties grown on two levels of mineral nutrition – N₁₆₀P₁₆₀K₁₆₀ and N₃₂P₃₂K₃₂ mg per kg of soil were determined. Results. It is shown that under mineral nutrition deficiency the photosynthesis rate in leaves of winter wheat has decreased and activity of SOD and APX has increased. This may be considered as a protective component of plant response to adverse factors. Conclusions. New high-yielding wheat Favorytka and Smuhlyanka are characterized by higher activity of CO₂ assimilation, and antioxidant enzymes as well as higher grain productivity under both optimal and low levels of mineral nutrition than old variety Myronivska 808.

Key words: Triticum aestivum L., varieties, photosynthesis, antioxidant enzymes, mineral nutrition