Abstract
Secondary metabolites (SMs) have high economic impact thanks to their exploitability in chemical, pharmaceutical and cosmetic industries. Trigonella foenum-graecum has an importance due to the production of bioactive compounds with pharmaceutical values. Among them, the alkaloid trigonelline is known for its role in the treatment of different human diseases. SM accumulation is influenced by environmental factors but is modulated by the application of exogenous compounds. Ethephon, a precursor of the phytohormone ethylene, was already used to influence SM accumulation. Our work is aimed at evaluating the accumulation of trigonelline and the phytohormone abscisic acid (ABA) when three factors were combined: i) two levels of water regimes (well-watered and water deficit), ii) ethephon treatments and iii) inoculation with an arbuscular mycorrhizal (AM)-based inoculum also leading to nodulation. The content of trigonelline and ABA was significantly affected by symbioses, showing high accumulation in AM-colonized plants irrespective of the water regimes applied. In terms of trigonelline accumulation with respect to ethephon treatments, while symbiotic plants showed a dose-dependent trend, non-symbiotic plants showed a significantly difference only when 550 ppm of ethephon was applied. In conclusion, our work provides new information on the effects of both ethephon and symbioses on plant growth and accumulation of valuable compounds, such as trigonelline, in fenugreek.
Highlights
In nature, plants produce a large plethora of organic bioactive compounds
Our study aimed to evaluate the water deficit effects on target metabolites in fenugreek, colonized by both arbuscular mycorrhizal (AM) fungi and nodule-forming symbionts in combination with exogenous ethephon application
Leguminous plants can host within their roots both symbionts concomitantly, forming the so-called tripartite symbioses largely studied to elucidate the complex dialogue among the partners [31]
Summary
Plants produce a large plethora of organic bioactive compounds. Several of them that do not directly affect life’s fundamental processes are referred as secondary metabolites (SMs) [1]. SMs are widely used as a natural chemical source in pharmaceutics, cosmetics and nutraceuticals, and there is an increased interest in the cultivation of plant species devoted to production of bioactive. Sci. 2020, 10, 2338 compounds [2]. The optimization of agronomic management strategies for secondary metabolite accumulation in nutraceutical species is still challenging [1,3]. Different studies reported that many environmental factors might affect the production and the accumulation of SMs in plants [1]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
