5. Effects of a biostimulant and a mineral fertilizer on the antioxidative defence system of chilling-exposed maize plants

Author: Rositsa Cholakova-Bimbalova, Lubka Koleva, Andon Vassilev

Abstract

The aim of the study was to investigate the effects of the biostimulant Terra-Sorb Foliar and the mineral fertilizer Poly-Plant on the antioxidative defence system of chilling-exposed young maize plants (Z. mays L., hybrid Kneza 307). The plants were grown as a substrate-hydroponic culture in a controlled environment at 25±1°C/20±1°C (day/night) temperature. At the appearance of the third leaf, the maize plants were exposed to chilling stress (constant 10°C) for 14 days.
Control plants were grown at 25/20°C. Seven days after the beginning of the chilling treatment, a part of the chilled plants were sprayed with 1% water solution of the biostimulant Terra-Sorb Foliar and with 1% water solution of the mineral fertilizer Poly-Plant. The plants were left to grow for another 7-day period under the same conditions. At the end of the experimental period, the antioxidant activity, polyphenols and anthocyanins content, as well as the guaiacol peroxidase (GPOD) activity, were determined. The applied biostimulant and the mineral fertilizer ameliorated to some extent the negative effect of the chilling treatment of the young maize plants.

Keywords: Zea mays L., chilling, antioxidant activity, anthocyanin, polyphenols, biostimulant, leaf fertilizer