Antioxidant defense and metabolic responses of lemon balm (Melissa officinalis L.) to Fe-nano-particles under reduced irrigation regimes

doi:10.1016/j.indcrop.2020.112338

Industrial Crops and Products

Volume 149, July 2020, 112338

https://doi.org/10.1016/j.indcrop.2020.112338 Get rights and content

Highlights

•
Water stress caused the overproduction of reactive oxygen species (ROS) in Melissa officinalis.
•
Fe nano particles activated antioxidant defense system in Melissa officinalis.
•
The antioxidant defense system protected plants against oxidative stress damages.
•
Fe nano particles resulted in alleviating oxidative stress in Melissa officinalis.
•
Fe NPs further increased the essential oil yield of Melissa officinalis.

Abstract

The use of nano particles (NPs) in agriculture is growing dramatically. However, the impact of Fe-NPs on physiological parameters and essential oil yield of lemon balm (Melissa officinalis L.) are still unknown. This research was conducted to address the effect of NPs of Fe oxide (Fe-NPs; 0, 5, 10, 20, 30 and 20 μM) on resistance against reduced irrigation by 80, 60 and 40 % Field Capacity (FC), in Melissa officinalis. Intensified drought, while significantly enhancing malondialdehyde (MDA), H₂O₂, proline conten, electrolyte leakage, total antioxidant activity (TAA), total phenolic content (TPC), antioxidant power and enzyme activities of lemon balm, caused marked reduction in chlorophyll content, ratio of variable to maximum fluorescence (Fv/Fm) and relative water content. The essential oil yield of Melissa officinalis increased with the decrease in irrigation from 80 to 60 % FC, and decreased with the water deficit increase to 40 % FC. Treating lemon balm plants with all levels of Fe NPs further increased the essential oil yield and improved physiological attributes of lemon balm. Fe NPs also resulted in alleviating oxidative stress by reducing TAA, TPC and antioxidant enzymes activities. The compensatory effect of Fe nanoparticle treatments in aleviating the negative effect of reduced irrigation was due to increase of proline accumulation and reduction of some antioxidant activities which increased drought tolerance of lemon balm. Reduced irrigation regimes as well as Fe NPs showed strong effects on essential oil production and composition in lemon balm.

Introduction

Lemon balm (Melissa officinalis L.) a perennial medicinal herb from Lamiaceae family. native to the littoral areas of the Mediterranean Sea up to Persia and widely spread in Middle and Southern Europe, the Balkans, Iran, South Africa, North America, India, the Ukraine, the Caucasus, and Middle Asia, has traditionally been used in folk medicine for treatment of digestive problems, pain and mental disorders (Moradkhani et al., 2010; Jamal Omidi et al., 2018). However, water scarcity is a serious threat to Melissa officinalis in arid and semi-arid regions, which reduces global crop yield as well as essential oil production (Bruce et al., 2007; Moradkhani et al., 2010; Rahimi et al., 2015; Jamal Omidi et al., 2018; Ahmadi et al., 2019). Most arable lands are located in arid and semiarid areas where water scarcity is a major constraint. Therefore, understanding the effect of drought stress on essential oil yield and quality of medicinal plants is an effective step in the growth of high yield and stable cultivars (Garcia Del Moral et al., 2003; Gholinezhad, 2017). Plants employ some physiological and biochemical strategies to increase stress tolerance and also generate a number of compounds to cope with stressful conditions, which need to be addressed to better understand their mechanisms (Yang et al., 2010). It is reported that the essential oil content of the plant and its components are affected by factors such as drought stress and fertilizer use (Srivastava et al., 1997; Min et al., 2005; Amuamuha et al., 2012). Fe, as one of the essential micronutrients, plays an important role in the metabolism of plants. It is a cofactor for about 140 enzymes that catalyze biochemical reactions in plant products (Fernandez et al., 2008; Mohamadipoor et al., 2013; Armin et al., 2014). In most arid and semiarid regions of Iran, Fe deficiency is not due to solubility and abundance. In such conditions, Fe is not readily available to the roots of many plants, as it is mainly found as stable compounds with low solubility at alkaline pH (Jelali et al., 2010; Amooaghaie and Roohollahi, 2017). Fe deficiency resulted from drought stress conditions can lead to oxidative stress, which induces protection mechanisms in plants to scavenge reactive oxygen species by enhancing the activities of some antioxidant enzymes such as CAT, POD and APX (Pestana et al., 2005; Jelali et al., 2010; Fahad et al., 2014; Gui et al., 2015; Amooaghaie and Roohollahi, 2016). Lemon balm (Melissa officinalis) is one of the herbs that are sensitive to Fe deficiency and severe symptoms of Fe such as chlorosis are often found in germinated plants in the field (Amooaghaie and Roohollahi, 2016). The uptake of Fe chelates such as Fe-ethylene diamineestracetic acid (Fe-EDTA) also significantly depends on soil conditions especially soil pH (Mohamadipoor et al., 2013). Therefore, the application of nanoparticles may improve the solubility and dispersion of insoluble nutrients in the soil, reducing the inactivation of nutrients and increasing their bioavailability (Naderi and Danesh-Shahraki, 2013; Askary et al., 2017a). Fe nanoparticles are very useful for plants due to the gradual release of Fe over a wide range of pH as a very rich source of Fe (Armin et al., 2014). Rui et al. (2017) also asserted that metal-based NPs could impact crop yield and quality. Therefore, in the present study, lemon balm was selected as the test plant to examine whether Fe oxide (Fe₂O₃) nanoparticles could alleviate the negative effects of drought stress. Due to the novelty of nanotechnology and insufficient information about NPs application especially Fe NPs in medicinal plants grown under drought sress, this study was conducted with aim to investigate the use of Fe oxide (Fe₂O₃) nanoparticles (Fe NPs) and different irrigation regims on physiological attributes, antioxidative activities and essential oil yield of lemon balm.

Section snippets

Experimental design

Lemon balm (Melissa officinalis L.) was used for this study. In 2018, the experiments were conducted under controlled environmental conditions (day T° 25 °C; night T° 20 °C; RH: 70 %), according to Askary et al. (2017) in an experimental greenhouse at Fars Agricultural and natural Resources research and education Center located in Eastern Shiraz city between 29°34′N, 52°35′E and an altitude of 1506 m) during 2018 using a factorial experiment based in a completely randomized design (CRD) with

Chlorophyll content, Fv/Fm measurement, RWC and electrolyte leakage (EL)

Table 1, Table 2 show the effect of Fe NPs on chlorophyll content and chlorophyll fluorescence. Mild drought stress (60 % FC) decreased chlorophyll content and Fv / Fm ratio of balm lemon and with increasing drought intensity (40 % FC), its effects on these traits were more negative. However, treatment with varying levels of Fe NPs significantly reduced the negative effects of drought on chlorophyll content (Fig. 1) and Fv/Fm ratio (Fig. 2) of Melissa officinalis. The highest of chlorophyll

Chlorophyll content and Fv/Fm ratio

The present study showed the responses of Melissa officinalis to Fe NPs under different levels of irrigation reduction. Our results showed a decrease in chlorophyll content and Fv / Fm ratio in plants grown under drought stress. Farooq et al. (2009) reported that drought stress could significantly reduced the amounts of chlorophyll content in the plant. A similar results are also reported for Melissa officinalis and Thymus species subjected to drought stress (Amooaghaie and Roohollahi, 2016;

Conclusion

According to these results, Fe nanoparticle treatments enabled lemon balm plants to sustain the biological membranes under stress resulting in better tolerance under reduced irrigation and further enhanced the essential oil yields. Thus, Fe nanoparticles may be selected to solve Fe deficiency problem in sustainable cultivation of Melissa officinalis in arid and semai arid lands of the world. Also in order to obtaining maximum essential oil percentage and yield of Melissa officinalis irrigation

Author contributions

Vahid Mohasseli, Farzad Farbod and Abolfath Moradi developed the experiment.

Vahid Mohasseli and Farzad Farbod provided assistance with metabolite analysis.

Abolfath Moradi analysed data.

Vahid Mohasseli drafted the manuscript which has been revised and reviewed by all other authors.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

The authors would like to thank Fars Agricultural and Natural Resources Research and Education Center for experimental purposes and financial support throughout this research.

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Antioxidant defense and metabolic responses of lemon balm (Melissa officinalis L.) to Fe-nano-particles under reduced irrigation regimes

Highlights

Abstract

Introduction

Section snippets

Experimental design

Chlorophyll content, Fv/Fm measurement, RWC and electrolyte leakage (EL)

Chlorophyll content and Fv/Fm ratio

Conclusion

Author contributions

Declaration of Competing Interest

Acknowledgments

Anal. Biochem.

Lebenson Wiss. Technol.

Curr. Opin. Plant Biol.

Braz. J. Pharmacogn.

Curr. Opin. Plant Biol.

Sci. Hort.

Plant Sci.

Ind. Crop. Prod.

Sci. Hort.

Sci. Hort.

Ind. Crop Prod.

J. Arid Environ.

Mol. Plant

Roles of enzymatic and non-enzymatic antioxidants in plants during abiotic stress

Crit. Rev. Biotechnol.

Improvement in drought tolerance of lemon balm, Melissa officinalis L. under the pretreatment of LED lighting

Plant Physiol. Biochem.

Growth, yield, chemical composition, and antioxidant activity of essential oils from two thyme specie under foliar application of Jasmonic acid and water deficit conditions

Hortic. Environ. Biotehnol.

Effects of water stress on the quantity and quality of essential oil of dill (Anethum graveolens L.)

J. Plant Process Func.

Effect of sodium nitroprusside on responses of Melissa officinalis to bicarbonate exposure and direct Fe deficiency stress

Photosynthetica

Effect of varying concentrations and time of Nano iron foliar application on the yield and essential oil of Pot marigold

Int. Res. J. Basic. Appl.

Changes in essential oil yield and composition at different parts of dill (Anethum graveolens L.) under Limited Irrigation Conditions

J. Agric. Sci. Sust. Prod.

The effect of water deficit on quantitative and qualitative characters of balm (Melissa officinalis L.)

Iran. J. Med. Arom. Plants

Effect of time and concentration of nano-Fe foliar application on yield and yield components of wheat

Int. J. Biosci.

Effect of NaCl and iron oxide nanoparticles on Mentha piperita essential oil composition

Environ. Exp. Bot.

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J. Plant Nutr.

Effects of iron nanoparticles on Mentha piperita L. under salinity stress

Biologija

The essential oil of lemon balm (Melissa officinalis L.), its components and using fields

J. Fac. Agric.

A re-examination of relative turgidity for estimating water deficits in leaves

Aust. J. Biol. Sci.

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Plant Soil

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Plant Physiol.

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