Influence of alcoholic extracts from Helianthus annnus L. roots on the photosynthetic activity of Sinapis alba L. cv. Barka plants

Abstract

Allelopathy substances stimulate or inhibit seed germination, growth and development of plant species living in their neighbouring, or occupying the same place directly after them. So far, considered to be insignificant, in recent years they have become an important element of field and laboratory study. The aim of this study was to determine the effect of ethanol extracts from the roots of common sunflower (Helianthus annuus L.), with 5 and 10% concentration, on the growth, photosynthetic activity of white mustard plants (Sinapis alba L. cv. Barka). The alcoholic extracts, with increasing concentrations, inhibited the growth of plants. Clear changes of the plants length watered with extracts during the growth phase were demonstrated. Compared to the control, the extracts reduced the content of chlorophylls a and b in S. alba leaves at each concentration in both phases. With an increase in allelopathic substance concentration, the chlorophyll a fluorescence parameters increasing in S. alba plants-watered extracts in the germination phase contrary to the growth phase were observed.

Keywords

• alcoholic extracts
• chlorophyll
• chlorophyll a fluorescence
• growth
• root