The Allelopathic Activity of Aqueous Extracts of Helianthus annuus L., Grown in Boreal Conditions, on Germination, Development, and Physiological Indices of Pisum sativum L.

Abstract

Evaluation of the allelopathy relationship between different crops is a sensible strategy fallowing the correct use of positive effects and to avoid the disadvantageous effects among plants. This study aimed to detect the allelopathic effect of aqueous extracts of sunflower (Helianthus annuus L.), grown in a boreal climatic zone, on the growth, subsequent development, and physiological traits of pea (Pisum sativum L.). Three factors have been studied: donor plant fertilization (unfertilized and fertilized), aqueous extracts from donor plant organs (leaves and stems (L+S), heads (H) and roots (R)); four concentrations of extracts (0%, 25%, 50% and 75%). The aqueous extracts from fertilized sunflower donor plant at 25% and 50% concentration acted as potential biostimulants that stimulated pea seed germination (SG), whereas L+S and R extracts at 75% concentration from unfertilized donor plant inhibited SG, at 4 days after sowing. The aqueous extracts demonstrated a stimulating effect on above-ground and root dry mass, compared to the control. The concentration of extracts demonstrated a significant inhibitory effect on SPAD. R extract revealed the strongest allelopathic effect on physiological traits of pea. L+S and H extracts at 25% concentration had stimulating effects, while 50% and 75% concentrations showed inhibiting effects on the photosynthetic rate. The water use efficiency, stomatal conductance, and stomatal limitation were inhibited, whereas, the transpiration rate, photosynthetic water use efficiency and intercellular CO2 concentration were stimulated, with an increasing of extract concentrations, comparatively to the control.

Plant-Based Biostimulants for Seeds in the Context of Circular Economy and Sustainability

“…Other aqueous extracts that have been tested on different plants confirmed multiple times the positive effects of these types of seed treatments on improving germination performance. These include Posidonia oceanica extracts applied on tomato [71], Atriplex halimus extract applied on sorghum (Sorghum bicolor) [72], and sunflower extracts applied to peas (Pisum sativum) [73].…”

The influence of water-soluble secretions of saffron seed on the germination of seeds of soft winter wheat varieties

“…Therefore, it is promising in the world to isolate biologically active compounds from saffron by-products (petals) for their use in the food, perfumery, and pharmaceutical industries (Mir et al, 2022;Serda-bernad et al, 2023). The study of the allopathic properties of plants is a promising area of research worldwide (Kheirabadi et al, 2020;Janusauskaite, 2023). Considering the biochemical composition of various organs of C. sativus L., its allopathic activity has been studied for a long time.…”

Investigating the Phytotoxic Potential of Helianthus annuus on Germination and Seedling Morphological Parameters of Two Target Poaceae Species: Spring Barley and Spring Wheat

“…The mode of activity of allelochemicals depends on their concentration. Low concentrations of them promote germination and growth, and high concentrations inhibit germination of seed and seedling growth [9,11,12]. Cultivation of similar plant species for many years leads to loss of soil nutrients, exacerbation of pests and diseases, deterioration of soil quality, and ecological imbalance, which ultimately has a significant influence on crop yield and production quality [13][14][15].…”