عنوان مقاله [English]
نویسنده [English]چکیده [English]
Background and Objectives
Allelopaty is regarded as a natural protecting strategy involving plant secoundary metabolites that influence the growth and development of surrounding biological system. Determining the mode of action of secondary metabolites as allelochemicals is one of the challenging aspects in allelopathic research. Today, allelochemicals have been proposed to cause oxidative stress in some of neighbor plants and inhibited their cell proliferation; however, its mechanism of action remains unexplored. The aim of the present study was to investigate the phytotoxic effect of leaf aqueous and methanol extract of Ferula foetida on physiological and biochemical processes during germination of tomato seeds.
Material and Methods
Effects of allelochemicals extracted from Ferula foetida on tomato (Lycopersicun escolentum) seed germination were investigated. For these purposes, a factorial experiment was conducted in a completely randomized design with four replications in plant physiology laboratory of Islamic Azad University, Neyshabur Branch. The first factor included allelopatic materials in three levels including 10% aqueous and methanolic extract of Ferula foetida(gathered in early vegetative growth period), and control and the second factor was time of sampling in 5 levels including sampling in 24,48,72,96 and 120 hours after imbibition.
The results showed that tomato seed viability, Malondialdehyde (MDA) content, hydrogen peroxide and antioxidative enzyme activity such as Superoxide dismutase (SOD), Catalase (CAT), Ascorbate peroxidase (APX) and Polyphenol oxidase (PPO) were significantly affected by treatment. In the earliest time of imbibition, both aqueous and methanol extracts, the activity of APX of tomato seed was the lowest, while the PPO showed the highest activity. The highest loss of seed viability, H2O2 and MDA, was in the seed treated with aqueous extract after 120 h, and the highest activity of antioxidative enzymes was in 72 h after exposure to water extract phytotoxins.
Our results showed that despite the activation of the antioxidant system by Ferula foetida phytotoxic, reactive oxygen species accumulation caused cellular damage which resulted in decrease of gradual loss of tomato’s seed viability. In addition, this study demonstrated that aqueus and alcholic extraction materials from Ferula foetida exhibited cosiderable allelochemical potential. Therfore, this compound could be utilized to generate a new generation of herbicidees that are more ecologically friendly.