Biostimulants and Plant Elicitors to Mitigate the Effect of Biotic and Abiotic Stress

A special issue of Horticulturae (ISSN 2311-7524). This special issue belongs to the section "Biotic and Abiotic Stress".

Deadline for manuscript submissions: closed (20 July 2022) | Viewed by 31614

Special Issue Editors

Department of Vegetal Biology, University of Murcia, 30100 Murcia, Spain
Interests: abiotic stress; phytohormones; secondary metabolism; biostimulants; plant biochemistry
Special Issues, Collections and Topics in MDPI journals
Centro de Biotecnología y Genómica de Plantas (UPM – INIA/CSIC), 28223 Madrid, Spain
Interests: abiotic stress; plant biochemistry; plant evolution; oxidative stress; secondary metabolism; RNA regulation
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Plant biostimulants are substance(s) and/or microorganisms applied to the plants or the rhizosphere with the aim of enhancing nutrition efficiency or product quality of crops, independently from the plant nutrient content. In the last decade, the use of biostimulants has been on the rise due to the increasing awareness of the need to promote sustainable agriculture worldwide. In addition to their role in enhancing plant performance, it is well established that biostimulants can also help plants to cope with abiotic stress. In this line, it is known that plant elicitors can increase plant tolerance to biotic stresses.

This Special Issue aims to shed light on the morphological, physiological, and biochemical processes triggered by the application of biostimulants and plant elicitors, ultimately leading to an increase in biotic and abiotic stress tolerance. Particular attention will be paid to the mechanisms to tackle increasingly frequent environmental stresses derived from climate change. Studies focused on these issues are welcome.

Dr. Begoña Miras-Moreno
Dr. Esther Novo-Uzal
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Horticulturae is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2200 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • biostimulants
  • elicitors
  • abiotic stress
  • biotic stress
  • secondary metabolism
  • climate change

Published Papers (12 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

13 pages, 1487 KiB  
Article
Effect of Exogenous Calcium on the Heat Tolerance in Rosa hybrida ‘Carolla’
by Han Wang, Yuxiao Shen, Kaixuan Wang, Songlin He, Wan-Soon Kim, Wenqian Shang, Zheng Wang and Liyun Shi
Horticulturae 2022, 8(10), 980; https://doi.org/10.3390/horticulturae8100980 - 21 Oct 2022
Cited by 1 | Viewed by 1478
Abstract
This study was designed to investigate the effects of exogenous calcium on the tolerance of Rosa hybrida ‘Carolla’ to high-temperature and the physiological mechanisms underlying this response. Leaves of ‘Carolla’ grown under stress were treated by spraying four different concentrations of calcium chloride [...] Read more.
This study was designed to investigate the effects of exogenous calcium on the tolerance of Rosa hybrida ‘Carolla’ to high-temperature and the physiological mechanisms underlying this response. Leaves of ‘Carolla’ grown under stress were treated by spraying four different concentrations of calcium chloride (CaCl2; 50, 100, 150, or 200 μM). The photosynthetic responses, antioxidant enzyme activities, and osmotic substance contents were measured under high-temperature stress at the flowering stage. Temperature-stressed ‘Carolla’ with CaCl2 treatment showed significantly increased chlorophyll (Chl) content, net photosynthetic rate (An), transpiration rate (E), stomatal conductance (gs), water use efficiency (WUE), superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX) activities together with proline (Pro), soluble sugar (SS), and soluble protein (SP) concentrations, while malonaldehyde (MDA) content and relative electrical conductivity (REC) were significantly reduced. The damages caused by high-temperature stress were alleviated by applying CaCl2. Among the CaCl2 treatments, 100 μM CaCl2 best minimized the damage caused by high-temperature to ‘Carolla’. This study showed that exogenous calcium could improve the tolerance of Rosa hybrida ‘Carolla’ to high-temperature stress by regulating photosynthesis, the antioxidant system, and osmotic substances. Full article
Show Figures

Figure 1

15 pages, 1290 KiB  
Article
Effect of Biostimulant Application on Plant Growth, Chlorophylls and Hydrophilic Antioxidant Activity of Spinach (Spinacia oleracea L.) Grown under Saline Stress
by Christophe El-Nakhel, Eugenio Cozzolino, Lucia Ottaiano, Spyridon A. Petropoulos, Sabrina Nocerino, Maria Eleonora Pelosi, Youssef Rouphael, Mauro Mori and Ida Di Mola
Horticulturae 2022, 8(10), 971; https://doi.org/10.3390/horticulturae8100971 - 20 Oct 2022
Cited by 17 | Viewed by 4384
Abstract
Irrigated agricultural lands are prone to salinity problems which may imperil horticultural crops by reducing growth, yield and even qualitative traits. Eco-friendly approaches such as biostimulant application and in particular protein hydrolysates from vegetal origin are implemented to mitigate salinity stress effects on [...] Read more.
Irrigated agricultural lands are prone to salinity problems which may imperil horticultural crops by reducing growth, yield and even qualitative traits. Eco-friendly approaches such as biostimulant application and in particular protein hydrolysates from vegetal origin are implemented to mitigate salinity stress effects on crops. For this reason, a greenhouse experiment on spinach irrigated with increasing concentrations of saline water (EC = 3 dS m−1 (EC3), 6 dS m−1 (EC6) and 9 dS m−1 (EC9), in addition to non-saline treatment (EC0)) was organized, while plants were subjected to foliar applications of a protein hydrolysate from vegetal origin on a weekly basis. The application of this biostimulant helped mitigate the adverse effects of saline stress, by increasing the SPAD index and total chlorophylls of spinach plants. Yield was significantly boosted under biostimulant treatment in saline conditions and reached the value obtained in control treatment (no biostimulants added) × EC0 in the case of EC 3 and 6 dS m−1. In addition, the number of leaves and plants m−1 was increased under biostimulant treatment, and most importantly the hydrophilic antioxidant activity of spinach, thus a qualitative aspect of great importance was also increased. Such results increase the knowledge on the effects of protein hydrolysates application on an important leafy vegetable and may help growers mitigate saline conditions and maintain high crop yield and high quality of the final product when no other source of irrigation water is available. Full article
Show Figures

Figure 1

17 pages, 8397 KiB  
Article
Effects of Exogenous Salicylic Acid (SA), 6-Benzylaminopurine (6-BA), or Abscisic Acid (ABA) on the Physiology of Rosa hybrida ‘Carolla’ under High-Temperature Stress
by Kaixuan Wang, Yuxiao Shen, Han Wang, Songlin He, Wan Soon Kim, Wenqian Shang, Zheng Wang and Liyun Shi
Horticulturae 2022, 8(9), 851; https://doi.org/10.3390/horticulturae8090851 - 18 Sep 2022
Cited by 10 | Viewed by 2371
Abstract
The study of the regulatory mechanism of exogenous plant growth regulators (PGRs) on the relevant physiological indicators is essential to maintain the normal growth of Rosa hybrida under high-temperature conditions. The photosynthetic and physiological characteristics of the ornamental cut rose Rosa hybrida ‘Carolla’ [...] Read more.
The study of the regulatory mechanism of exogenous plant growth regulators (PGRs) on the relevant physiological indicators is essential to maintain the normal growth of Rosa hybrida under high-temperature conditions. The photosynthetic and physiological characteristics of the ornamental cut rose Rosa hybrida ‘Carolla’ under high temperature were studied by spraying leaves with various concentrations of exogenous salicylic acid (SA; 0.5, 1.0, 1.5, or 2.0 mmol·L−1), 6-benzylaminopurine (6-BA; 10, 20, 30, or 50 μmol·L−1), abscisic acid (ABA; 10, 20, 30, or 50 mg·L−1), or distilled water (control). The results indicated that a foliar spray of either SA, 6-BA, or ABA could mitigate the impact of high temperatures. Compared to the control, the application of SA, 6-BA, or ABA increased the net CO2 assimilation rate (An), transpiration rate (E), stomatal conductance (Gs), and water use efficiency (WUE) of ‘Carolla’, while decreasing the leaf relative electrical conductivity (REC) and malondialdehyde (MDA) content. The applications of SA, 6-BA, or ABA increased the activities of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX) and altered the proline (Pro), soluble protein, and soluble sugar contents. The results showed that foliar sprays of SA, 6-BA, or ABA could enhance the heat tolerance of ‘Carolla’ by promoting photosynthesis, cell membrane structural stability, antioxidant enzyme activity, and osmoregulation in plants under high-temperature stress. The experiment showed that 1.5 mmol·L−1 SA, 20 μmol·L−1 6-BA, or 75 μmol·L−1 ABA could alleviate the damage caused by high temperatures, with 20 μmol·L−1 6-BA having the best effect. Full article
Show Figures

Figure 1

18 pages, 6151 KiB  
Article
Application of Rosemary and Eucalyptus Essential Oils on the Preservation of Cucumber Fruit
by Panayiota Xylia, Antonios Chrysargyris, Durray Shahwar, Zienab F. R. Ahmed and Nikolaos Tzortzakis
Horticulturae 2022, 8(9), 774; https://doi.org/10.3390/horticulturae8090774 - 26 Aug 2022
Cited by 16 | Viewed by 2475
Abstract
Cucumber (Cucumis sativus L.) is one of the most significant and frequently produced vegetable crops. However, because of its high perishability, keeping its quality from the farm to the market is a challenging problem. Various techniques have been employed to reduce postharvest [...] Read more.
Cucumber (Cucumis sativus L.) is one of the most significant and frequently produced vegetable crops. However, because of its high perishability, keeping its quality from the farm to the market is a challenging problem. Various techniques have been employed to reduce postharvest losses and to extend the shelf life of vegetables and fruits. Recently, another approach is the application of eco-friendly elicitors as essential oils-EOs to prevent fruit decay and enhance its quality. Therefore, the purpose of this study was to assess the effectiveness of an environmentally friendly product (EP) based on rosemary and eucalyptus essential oils and two distinct application techniques (vapor and dipping) on maintaining quality characteristics of cucumber fruits during storage at 11 °C and ~90% relative humidity (RH) for two weeks. The results showed that the EP was successful in preserving cucumber fruit quality. Vaporized cucumbers did not show any significant weight losses, whereas dipped cucumbers showed a greater weight loss at 0.4% EP (3.5%) compared with the control (3%). Fruit treated with EP (vapor or dipping) or chlorine maintained firmness and ripening index during storage. Total soluble solids (TSS) levels were similar in all vapor-treated fruit while dipping application of chlorine increased TSS (4 oBrix) after 7 days of storage. Vapor or dipping application of EP or chlorine had a slight effect on cucumber color. Vaporized (EP or chlorine) cucumbers had comparable total phenols and antioxidant activity when compared with the control treatment, while dipped fruit had lower total phenols content and antioxidant activity at 0.8% EP after 7 days of storage. These findings indicate that the evaluated EP (vapor or dipping) can be a potential natural alternative to be used to preserve fresh produce instead of the common sanitizing agent (chlorine). Nevertheless, the application method and conditions should be further optimized for every product. Full article
Show Figures

Figure 1

11 pages, 1861 KiB  
Article
Physiological Study of the Efficacy of Archer® Eclipse in the Protection against Sunburn in Cucumber Plants
by Iván Navarro-Morillo, Francisco Garcia-Sanchez, Jose Maria Camara-Zapata, Eloy Navarro-León, María José Izquierdo-Ramos, Begoña Blasco and Juan Manuel Ruiz
Horticulturae 2022, 8(6), 500; https://doi.org/10.3390/horticulturae8060500 - 04 Jun 2022
Cited by 2 | Viewed by 2231
Abstract
Sunburn is an important issue affecting the yield of many crops, mainly in arid and semi-arid regions. Excessive solar radiation and high temperatures can reduce growth and cause leaf chlorosis, oxidative stress, and photosynthesis impairment. It is thus necessary to develop agricultural techniques [...] Read more.
Sunburn is an important issue affecting the yield of many crops, mainly in arid and semi-arid regions. Excessive solar radiation and high temperatures can reduce growth and cause leaf chlorosis, oxidative stress, and photosynthesis impairment. It is thus necessary to develop agricultural techniques to protect plants in a cost-effective and reproducible manner. A potential method is through the spray of protective compounds based on particulate films, such as those based on kaolin. The objective of this study is to evaluate the effects of spraying the protective product Archer® Eclipse, created by Atlántica Agrícola S.A. (Alicante, Spain), on sunburn damage in a sensitive species such as the cucumber plants (Cucumis sativus L.). To evaluate the effects of sunburn on the plants, parameters related to biomass, leaf temperature, photosynthesis, and oxidative stress were analysed. Plants sprayed with Archer® Eclipse showed fewer sunburn symptoms and obtained 43% more shoot biomass than those that were not treated. In addition, plants sprayed with Archer® Eclipse showed 3 °C lower leaf temperatures, higher photosynthesis performance, 88% more water use efficiency, and 21% more chlorophyll concentration. Finally, plants treated with Archer® Eclipse presented 6% less accumulations of carotenoids and 67% less total phenols, but lower oxidative stress indicators. In conclusion, this study confirms the efficiency of Archer® Eclipse in protecting a sensitive vegetable plant such as the cucumber from sunburn-inducing conditions. Full article
Show Figures

Figure 1

15 pages, 303 KiB  
Article
Biostimulatory Action of a Plant-Derived Protein Hydrolysate on Morphological Traits, Photosynthetic Parameters, and Mineral Composition of Two Basil Cultivars Grown Hydroponically under Variable Electrical Conductivity
by Michele Ciriello, Luigi Formisano, Christophe El-Nakhel, Giandomenico Corrado and Youssef Rouphael
Horticulturae 2022, 8(5), 409; https://doi.org/10.3390/horticulturae8050409 - 06 May 2022
Cited by 5 | Viewed by 1930
Abstract
Hydroponics is a viable alternative to open field cultivation for year-round vegetable production in urban areas. However, the total dependence on external chemical inputs (fertilizers) makes these systems often less environmentally sustainable. In this perspective, the use of biostimulants could represent a valuable [...] Read more.
Hydroponics is a viable alternative to open field cultivation for year-round vegetable production in urban areas. However, the total dependence on external chemical inputs (fertilizers) makes these systems often less environmentally sustainable. In this perspective, the use of biostimulants could represent a valuable and eco-friendly tool to limit the excessive use of fertilizers without a negative impact on the yield. To this end, our work aimed to evaluate the productive and physiological response of two cultivars of ‘Genovese’ basil (Eleonora and Italiano Classico) for the industrial production of “pesto” grown for 22 days in two nutrient solutions with different electrical conductivity (1 and 2 dS m−1) and the application of two doses of protein hydrolysates (0.15- and 0.30-mL L−1 of Trainer® in the nutrient solution). The mineral profile was evaluated by ion chromatography coupled with a conductivity detector, while pigments were evaluated by UV-Vis spectrophotometry. Generally, the nutrient solution concentration did not significantly affect the fresh yield of the two cultivars tested. On the contrary, the use of the maximum dose of biostimulant (BT2 = 0.30 mL L−1 of nutrient solution) increased fresh yield, leaf area, and ACO2 by 20.7, 27.5, and 17.6%, respectively, compared with the control. Using the lowest dose of biostimulant (BT1 = 0.15 mL L−1 of the nutrient solution) reduced nitrate by 6.6% compared with the control. The results obtained showed that basil cultivation in a floating raft system combined with biostimulant in the nutrient solution could be an excellent solution to improve productivity, reduce nitrate, and cut fertilizer costs. Full article
13 pages, 721 KiB  
Article
Effects of Biogenic ZnO Nanoparticles on Growth, Physiological, Biochemical Traits and Antioxidants on Olive Tree In Vitro
by Luca Regni, Daniele Del Buono, Maurizio Micheli, Simona Lucia Facchin, Ciro Tolisano and Primo Proietti
Horticulturae 2022, 8(2), 161; https://doi.org/10.3390/horticulturae8020161 - 12 Feb 2022
Cited by 25 | Viewed by 3048
Abstract
Currently, there is an increasing interest in nanotechnology, since some nanomaterials can enhance crop growth, yield, nutritional status, and antioxidant defences. This work aimed to investigate for the first time the influence of zinc oxide nanoparticles (ZnO-NPs) on the in vitro growth and [...] Read more.
Currently, there is an increasing interest in nanotechnology, since some nanomaterials can enhance crop growth, yield, nutritional status, and antioxidant defences. This work aimed to investigate for the first time the influence of zinc oxide nanoparticles (ZnO-NPs) on the in vitro growth and biochemical parameters of the olive tree (cv. Moraiolo). With this goal, biogenic ZnO-NPs (spherical shape and dimensions in the range of 10–20 nm), deriving from a green synthesis carried out with a Lemna minor L. extract were used. Different concentrations (0, 2, 6 and 18 mg L−1) of ZnO-NPs were added to the olive growth medium (OM substrate), and three sub-cultures of 45 days each were carried out. ZnO-NPs at 6 and 18 mg L−1 enhanced some growth parameters in the olive tree explants, such as the number of shoots, green fresh and total dry weight. Moreover, the abovementioned concentrations raised the chlorophyll a and b content and soluble protein. Finally, concerning the dosage applied, the treatments stimulated the content of carotenoids, anthocyanins, total phenol content (TPC), and the radical scavenging activity towards DPPH (2.2-diphenyl-1-picrylhydrazyl). In conclusion, this study highlighted that biogenic ZnO-NPs exerted beneficial effects on the olive tree explants in vitro, improving the effectiveness of the micropropagation technique. Full article
Show Figures

Figure 1

10 pages, 550 KiB  
Article
Sunscreen Based on Dicarboxylic Acid Salts Applications to Blueberries (Vaccinium corymbosum L.) Plants: Effects on Water Stress Tolerance and Productivity
by Gastón Gutiérrez-Gamboa, Mario Guerrero-Méndez, Miguel Araya-Alman, Nicolás Verdugo-Vásquez, Héctor Valdés-Gómez and César Acevedo-Opazo
Horticulturae 2022, 8(2), 95; https://doi.org/10.3390/horticulturae8020095 - 20 Jan 2022
Cited by 3 | Viewed by 2307
Abstract
Background: Recently, antitranspirant or radiation-reflective products have been studied in several crops to mitigate the negative effects of global warming in Mediterranean climates. Nevertheless, to our knowledge, there is a scarce availability of information studying their effects on blueberries and much less from [...] Read more.
Background: Recently, antitranspirant or radiation-reflective products have been studied in several crops to mitigate the negative effects of global warming in Mediterranean climates. Nevertheless, to our knowledge, there is a scarce availability of information studying their effects on blueberries and much less from applications of sunscreens elaborated based on a mixture of dicarboxylic acids. Methods: Controls and three treatments were performed in ‘Duke’ and ‘Star’ blueberries as follows: (i) control without water stress (T1 = 100% ETc); (ii) foliar application of sunscreen in plants without water stress (T2 = 100% ETc + sunscreen); (iii) water stress in plants without foliar application of sunscreen (T3 = 50% ETc); (iv) foliar application of the sunscreen in plants with water stress (T4 = 50% ETc + sunscreen). Stem water potential (Ψs), stomatal conductance (gs), yield, berry weight and berry total soluble solids were determined. (3) Results: As expected, the decrease in irrigation frequency in water stress treatments (T3 and T4) allowed for a decrease in the water applied at 25% compared to non-stressed plants (T1 and T2). This resulted in an increase in the Ψs on the days closest to harvest in both varieties, decreasing gs in blueberries plants subjected to water stress conditions. Sunscreen applications to Duke plants subjected to water stress (T4) induced higher total berry soluble solids than the treatments performed in non-stressed plants (T1 and T2). Sunscreen applications to Star plants subjected to water stress (T4) promoted similar gs levels and did not affect total soluble solids concerning irrigated plants (T1 and T2). (4) Conclusions: The results suggest that the response to water stress to sunscreen application based on dicarboxylic acid salts depended on the cultivar. Therefore, despite the novelty of this research, it is necessary to perform long-term studies to establish accurate conclusions. Full article
Show Figures

Figure 1

26 pages, 1082 KiB  
Article
Foliar Supplementation of Clove Fruit Extract and Salicylic Acid Maintains the Performance and Antioxidant Defense System of Solanum tuberosum L. under Deficient Irrigation Regimes
by El-Sayed M. Desoky, Eman Selem, Mohamed F. Abo El-Maati, Asem A. S. A. Hassn, Hussein E. E. Belal, Mostafa M. Rady, Mohammad S. AL-Harbi and Esmat F. Ali
Horticulturae 2021, 7(11), 435; https://doi.org/10.3390/horticulturae7110435 - 24 Oct 2021
Cited by 9 | Viewed by 2198
Abstract
A field trial was conducted twice (in 2020 and 2021) to evaluate the effect of clove fruit extract (CFE) and/or salicylic acid (SA), which were used as a foliar nourishment, on growth and yield traits, as well as physiological and biochemical indices utilizing [...] Read more.
A field trial was conducted twice (in 2020 and 2021) to evaluate the effect of clove fruit extract (CFE) and/or salicylic acid (SA), which were used as a foliar nourishment, on growth and yield traits, as well as physiological and biochemical indices utilizing potato (Solanum tuberosum L.) plants irrigated with deficient regimes in an arid environment. Three drip irrigation regimes [e.g., well watering (7400 m3 ha−1), moderate drought (6200 m3 ha−1), and severe drought (5000 m3 ha−1)] were designed for this study. The tested growth, yield, and photosynthetic traits, along with the relative water content, were negatively affected, whereas markers of oxidative stress (hydrogen peroxide and superoxide), electrolyte leakage, and peroxidation of membrane lipids (assessed as malondialdehyde level) were augmented along with increased antioxidative defense activities under drought stress. These effects were gradually increased with the gradual reduction in the irrigation regime. However, under drought stress, CFE and/or SA significantly enhanced growth characteristics (fresh and dry weight of plant shoot and plant leaf area) and yield components (average tuber weight, number of plant tubers, and total tuber yield). In addition, photosynthetic attributes (chlorophylls and carotenoids contents, net photosynthetic and transpiration rates, and stomatal conductance) were also improved, and defensive antioxidant components (glutathione, free proline, ascorbate, soluble sugars, and α-tocopherol levels, and activities of glutathione reductase, peroxidase, superoxide dismutase, catalase, and ascorbate peroxidase) were further enhanced. The study findings advocate the idea of using a CFE+SA combined treatment, which was largely efficient in ameliorating potato plant growth and productivity by attenuating the limiting influences of drought stress in dry environments. Full article
Show Figures

Figure 1

14 pages, 1762 KiB  
Article
The Mycorrhiza-and Trichoderma-Mediated Elicitation of Secondary Metabolism and Modulation of Phytohormone Profile in Tomato Plants
by Giusy Iula, Begoña Miras-Moreno, Luigi Lucini and Marco Trevisan
Horticulturae 2021, 7(10), 394; https://doi.org/10.3390/horticulturae7100394 - 12 Oct 2021
Cited by 6 | Viewed by 3212
Abstract
Arbuscular mycorrhiza and Trichoderma are well-known beneficial fungi whose plant growth promotion and defense elicitation effects are known. However, the molecular and biochemical processes underlying the beneficial effects of these priming microorganisms have not been fully elucidated yet. On this basis, the present [...] Read more.
Arbuscular mycorrhiza and Trichoderma are well-known beneficial fungi whose plant growth promotion and defense elicitation effects are known. However, the molecular and biochemical processes underlying the beneficial effects of these priming microorganisms have not been fully elucidated yet. On this basis, the present work aimed to use metabolomics to dissect comprehensively the modulation of secondary metabolism induced by mycorrhiza and Trichoderma, using tomato as a model plant. To this aim, either mycorrhiza or Trichoderma were applied to tomato roots at transplanting using a commercial formulation and then harvested once the mutualistic relationship was well established. Shoots were analyzed using an MS-based untargeted metabolomics approach, and differential metabolites identified by multivariate statistics were subjected to pathway analysis. Together with promoting plant growth, the treatments induced a broad molecular reprogramming with the phenylpropanoid biosynthetic pathway (including defense phenolics like coumarins and glycosylated anthocyanins) being strongly elicited. An accumulation of auxins, cytokinins, and jasmonate (especially after treatment with Trichoderma) could be observed concerning phytohormone profiles. Overall, the broad and distinctive effects triggered by mycorrhiza and Trichoderma in tomato secondary metabolism supported both plant growth promotion and immunity. Full article
Show Figures

Figure 1

Review

Jump to: Research

15 pages, 555 KiB  
Review
Plant Melatonin: Regulatory and Protective Role
by Runxian Song, Faujiah Nurhasanah Ritonga, Haiyang Yu, Changjun Ding and Xiyang Zhao
Horticulturae 2022, 8(9), 810; https://doi.org/10.3390/horticulturae8090810 - 03 Sep 2022
Cited by 7 | Viewed by 1678
Abstract
Melatonin is an antioxidant that is widely distributed in plants and animals. It is a conservative molecule. In early studies, scientists often used isolation and identification techniques to observe whether the endogenous melatonin cycle in plants was related to the external photoperiod, plant [...] Read more.
Melatonin is an antioxidant that is widely distributed in plants and animals. It is a conservative molecule. In early studies, scientists often used isolation and identification techniques to observe whether the endogenous melatonin cycle in plants was related to the external photoperiod, plant growth, and development cycles, including seed germination, plant rooting, and floral induction. With the development of isolation and identification technology, there is ample evidence that plants possess a variety of melatonin-synthesis pathways. The comprehensive application of molecular biology, genomics, and computational biology has also led to a comprehensive understanding of the physiological functions of plant melatonin. In this paper, we not only highlight the candidate genes from Arabidopsis thaliana and Oryza sativa that might be contributing to increasing plant endogenous melatonin but also elucidate and characterize the role of melatonin in plant growth and development in response to biotic and abiotic stresses. Full article
Show Figures

Figure 1

19 pages, 1388 KiB  
Review
Application of Elicitors in Grapevine Defense: Impact on Volatile Compounds
by Rafia Salifu, Chunxia Chen, Faisal Eudes Sam and Yumei Jiang
Horticulturae 2022, 8(5), 451; https://doi.org/10.3390/horticulturae8050451 - 17 May 2022
Cited by 5 | Viewed by 2689
Abstract
Elicitors as alternatives to agrochemicals are widely used as a sustainable farming practice. The use of elicitors in viticulture to control disease and improve phenolic compounds is widely recognized in this field. Concurrently, they also affect other secondary metabolites, such as aroma compounds. [...] Read more.
Elicitors as alternatives to agrochemicals are widely used as a sustainable farming practice. The use of elicitors in viticulture to control disease and improve phenolic compounds is widely recognized in this field. Concurrently, they also affect other secondary metabolites, such as aroma compounds. Grape and wine aroma compounds are an important quality factor that reflects nutritional information and influences consumer preference. However, the effects of elicitors on aroma compounds are diverse, as different grape varieties respond differently to treatments. Among the numerous commercialized elicitors, some have proven very effective in improving the quality of grapes and the resulting wines. This review summarizes some of the elicitors commonly used in grapevines for protection against biotic and abiotic stresses and their impact on the quality of volatile compounds. The work is intended to serve as a reference for growers for the sustainable development of high-quality grapes. Full article
Show Figures

Figure 1

Back to TopTop