The Inhibitory Effects of Coumarin on the Germination of Durum Wheat (Triticum turgidum ssp. durum, cv. Simeto) Seeds

Abstract

The event chain leading to germination blockage in durum wheat (Triticum turgidum ssp. durum Desf.) seeds exposed to the allelochemical coumarin (2H-chromen-2-one) was studied. The physiological and biochemical aspects thought to be critical for a successful seed germination were measured. At concentrations above 200 microM: , coumarin inhibited seed germination in a concentration-dependent manner. Inhibition occurred early during seed imbibition (phase I), was rapid, and irreversible. During phase I, coumarin inhibited water uptake, electrolyte retention capacity, and O(2) consumption. Later on, coumarin delayed the reactivation of peroxidases, enhanced the activity of superoxide dismutase, decreased the activities of selected marker enzymes for metabolic resumption, and repressed the transcription of molecular chaperones involved in secretory pathways. Insufficient and/or late seed rehydration caused by coumarin could have delayed membrane stabilization or decreased respiratory O(2) consumption, both of which are conducive to an overproduction of reactive O(2) species. Being unbalanced by an adequate upsurge of antioxidant defense systems, the resulting oxidative stress might have ultimately interfered with the germination program.

Swailing affects seed germination of plants of European bio-and agricenosis in a different way

“…Such a material potentially could emit physiologically active volatiles, too, e.g. coumarins [28]. However, similar results were obtained when a piece of laboratory filter paper or empty Petri dish was used in the control instead of dried meadow sward (data not shown).…”

Short-term effects of coumarin along the maize primary root axis

“…3,4 Like other allelochemicals, such as phenolic compounds released from living plants into the environment, 5 coumarin can influence many physiological and biochemical processes: root growth, [6][7][8][9] nitrate uptake and metabolism, 10,11 respiration and photosynthesis 12 and germination. [13][14][15] The effect of coumarin is species-specific 7,15 and concentration-dependent, often stimulatory at low and inhibitory at high concentrations. 9,14 Coumarin has been widely studied for allelopathic effects on root growth, organ considered the primary target of this compound.…”

“…[13][14][15] The effect of coumarin is species-specific 7,15 and concentration-dependent, often stimulatory at low and inhibitory at high concentrations. 9,14 Coumarin has been widely studied for allelopathic effects on root growth, organ considered the primary target of this compound. 16 Earlier investigations indicated clearly that coumarin changed root cell polarity of growth, causing an inhibition of longitudinal root cell elongation accompanied by a simultaneous stimulation of radial expansion.…”

Herbicidal potential of phenolic and cyanogenic glycoside compounds isolated from Mediterranean plants

“…In fact, the C7 hydroxyl groups in 7-hydroxycoumarin (compound 5) was important for increasing the activity of coumarin (Pan et al, 2015). According to Pergo et al (2008), the coumarin is a species-specific and concentration-dependent, with a stimulatory and inhibitory effects at low and high concentrations, respectively (Abenavoli et al, 2006). Generally, coumarin is widely dispersed in plant and can influence several physiological and biochemical processes of germination (Pergo et al, 2008), respiration, root growth, nitrate uptake and metabolism (Abenavoli et al, 2003), and photosynthesis (Moreland & Novitzky, 1987).…”