Melatonin, an underestimated natural substance with great potential for agricultural application

Abstract

Melatonin (MEL) was thought to be only a neurotransmitter found in vertebrates until its detection in other organisms including plants. Although the number of publications on MEL function in plants is expanding, the knowledge of this subject is still insufficient. Among many functions which MEL performs in plants, its role as an antioxidant and a growth promoter is most supported by experimental evidence. This compound is an independent plant growth regulator and it may mediate the activities of other plant growth regulators. Due to its antioxidant properties MEL may also stabilize cell redox status and protect tissues against reactive oxygen and nitrogen species which accumulated under stressful environment. Some researchers propose that MEL could be used to improve the phytoremediation efficiency of plants against different pollutants. In this paper we show that exogenous MEL applied into the seeds could be a good biostimulator improving not only seed germination, seedling/plant growth but also crop production especially under stress conditions. We also believe that this compound can increase food quality (the aspect of functional food) and may improve human health. Since MEL is inexpensive and safe for animals and humans its application as a biostimulator could be a good, feasible and cost-effective method useful in agriculture.

Alleviation of salinity stress on Vicia faba L. plants via seed priming with melatonin

“…The obtained data show an enhancement effect of melatonin on vegetative growth parameters of faba bean plants irrigated either with tap water or diluted seawater (Table 1). In this connection, Janas and Posmyk (2013) mentioned that exogenously applied melatonin improved developmental processes during both vegetative and reproductive growth under stress conditions. Moreover, due to its antioxidant properties, melatonin protected the roots of barley from the damaging effects of NaCl, ZnSO 4 and H 2 O 2 (Tan et al, 2010).…”

“…(Arnao and Hernández-Ruiz, 2009). Melatonin is soluble in both water and lipid so it may act as a universal hydrophilic and hydrophobic antioxidant (Janas and Posmyk, 2013). Several authors hypothesized that melatonin may possess some auxin-like effects (Kolár and Machackova, 2005) and may act as a regulatory molecule in plants (Van Tassel et al, 2001).…”

Involvement of melatonin applied to Vigna radiata L. seeds in plant response to chilling stress

“…These techniques are one of the physiological methods improving seed performance and providing faster and synchronized germination. Seed priming can be combined with the application of plant hormones [19] and biostimulators (e.g., proline [20] and MEL [8,21]). The objective of this study was to determine the effects of H and H-MEL on MEL and phenolic levels and PAL activity as well as on membrane integrity and antioxidant activity of extracts from roots of chilled and re-warmed seedlings.…”

Exogenous melatonin expediently modifies proteome of maize (Zea mays L.) embryo during seed germination

“…Since melatonin is safe for environment (non-toxic, of natural origin, biodegradable) as well as being inexpensive, it is using as a supplement of various priming methods may be a reliable and cost-effective manner for beneficial seed quality modifications and could be economically favourable for organic farming (Janas and Posmyk 2013). Plant biostimulation by melatonin application is a promising tool to enhance ecological crops and to support safety-food production.…”

“…Our previous research showed efficient conditioning methods for cucumber, cabbage and corn seed quality amelioration, with simultaneous melatonin application Posmyk et al 2008Posmyk et al , 2009a. In general, results of our team suggest that melatonin (N-acetyl-5-methoxytryptamine) has a significant potential for biostimulation of plants (Janas and Posmyk 2013). Moreover, it is of natural origin, biodegradable, and harmless.…”