Plants

Research

Jump to: Review

17 pages, 357 KiB

Open AccessArticle

Understanding the Postharvest Phytochemical Composition Fates of Packaged Watercress (Nasturtium officinale R. Br.) Grown in a Floating System and Treated with Bacillus subtilis as PGPR

by Giuseppe Pignata, Andrea Ertani, Manuela Casale, Diana Niñirola, Catalina Egea-Gilabert, Juan A. Fernández and Silvana Nicola

Plants 2022, 11(5), 589; https://doi.org/10.3390/plants11050589 - 22 Feb 2022

Cited by 1 | Viewed by 1678

Abstract

The physiological changes and phytochemical pathways of processed watercress (Nasturtium officinale R. Br.) undergone during storage are not well known. The objective of this work was to evaluate the respiration rate and the inherent and external quality of watercress inoculated with B. [...] Read more.

The physiological changes and phytochemical pathways of processed watercress (Nasturtium officinale R. Br.) undergone during storage are not well known. The objective of this work was to evaluate the respiration rate and the inherent and external quality of watercress inoculated with B. subtilis and packaged as a fresh-cut product and stored at 4 °C for 11 days. Watercress was grown using continuous flotation (FL) in a greenhouse using substrate disinfection and inoculated or not with Bacillus subtilis as a plant-growth-promoting rhizobacteria (PGPR). The fresh-cut watercress respiration rate and phytochemical profile changed during the shelf life. The inherent phytochemical compounds were retained during the storage of the fresh-cut salad bags. The best results were found in watercress grown in a disinfected substrate but were less satisfactory when seeds and substrates were inoculated with PGPR. In general, the external quality and the pigment contents progressively decreased during the shelf life and the browning enzyme activities responsible for phenolic oxidation increased at different intensities throughout storage. At the end of the shelf-life period, the fresh weight loss of the fresh-cut product was less than 1% of the original weight. The results demonstrated that watercress grown in FL is a standardised baby leaf vegetable that is suitable for processing in the fresh-cut industry and for storing for more than 10 days. Unclear results were obtained for Bacillus subtilis in the postharvest period due to the inconsistent responses of the different analysed parameters. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

23 pages, 1155 KiB

Open AccessArticle

Induction of Catharanthus roseus Secondary Metabolites When Calotropis procera Was Used as Bio-Stimulant

by Amany H. A. Abeed, Mohammed Ali, Esmat F. Ali, Ali Majrashi and Mamdouh A. Eissa

Plants 2021, 10(8), 1623; https://doi.org/10.3390/plants10081623 - 06 Aug 2021

Cited by 15 | Viewed by 3423

Abstract

Available information associated with Calotropis procera posted its phytotoxic effect as bio-herbicide scarce works studied its stimulatory/nutritive effect. A pot experiment was performed to assess the validity of using Calotropis procera (C. procera) leaves extract as a bio-stimulant for the growth [...] Read more.

Available information associated with Calotropis procera posted its phytotoxic effect as bio-herbicide scarce works studied its stimulatory/nutritive effect. A pot experiment was performed to assess the validity of using Calotropis procera (C. procera) leaves extract as a bio-stimulant for the growth and quality of a medicinal plant Catharanthus roseus (C. roseus) evaluated by some physio-biochemical indices. Different types of C. procera leaves extracts (CLEs) (methanolic, cold water and autoclaved water extracts) were delivered by two different modes of application. The results revealed that application of CLEs as irrigation or foliar spraying caused a stimulation effect on C. roseus plant. Root and shoot length, dry and fresh weight were significantly improved due to CLEs applications. C. roseus bioactive molecules such as anthocyanins, phenolics, flavonoids, alkaloids, ascorbic acid, reduced glutathione and

α

-tocopherol were abundance increased significantly with CLEs applications. Reactive oxygen species (ROS) decreased explaining the involvement of CLEs in induction of antioxidant enzymes catalase, ascorbate peroxidase, polyphenol oxidase, guaiacol peroxidase and glutathione-S-transferase for modifying cell oxidative status witnessed by lower lipid peroxidation that kept below the untreated plants’ baseline reflected the improvement of growth and quality rather than phytotoxic effect. The promotion of wholesome-promoting secondary metabolites by CLEs was closely correlated to elevated phenylalanineammonialyase activity. The comparable efficient effect induced by all treatments might be judged by the relation between C. procera phytochemicals and C. roseus metabolism (donor-receiver relation). It is concluded that application of CLEs can be a promising approach for improving the yield and quality of plants despite using polluting fertilizers. The current investigation may provide a matrix for coming studies to seek illustration of numerous plants’ response to C. procera extracts. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

13 pages, 1166 KiB

Open AccessArticle

Integration of Ultrasound into the Development of Plant-Based Protein Hydrolysate and Its Bio-Stimulatory Effect for Growth of Wheat Grain Seedlings In Vivo

by Karolina Trakselyte-Rupsiene, Grazina Juodeikiene, Darius Cernauskas, Elena Bartkiene, Dovile Klupsaite, Daiva Zadeike, Joana Bendoraitiene, Jonas Damasius, Jonas Ignatavicius and Sidona Sikorskaite-Gudziuniene

Plants 2021, 10(7), 1319; https://doi.org/10.3390/plants10071319 - 28 Jun 2021

Cited by 8 | Viewed by 2442

Abstract

This study was dedicated to increasing the efficiency of producing plant-based protein hydrolysate using traditional and non-traditional treatments. Low- and high frequency ultrasound (US) at different intensities were applied to corn steep liquor (CSL) at 50 °C for 30 min, and enzymatic hydrolysis [...] Read more.

This study was dedicated to increasing the efficiency of producing plant-based protein hydrolysate using traditional and non-traditional treatments. Low- and high frequency ultrasound (US) at different intensities were applied to corn steep liquor (CSL) at 50 °C for 30 min, and enzymatic hydrolysis was performed using industrially produced alkaline protease. The efficiency of US and enzymatic treatments was characterized by protein solubility (soluble protein (SP) content, hydrolyzed protein (HP) concentration, and free amino acid (FAA) profile) and kinetic parameters: Michaelis–Menten constant (KM) and apparent breakdown rate constant (kA). A significant effect of 37 kHz US pre-treatment for CSL enzymatic hydrolysis was found and resulted in the highest HP concentration (17.5 g/L) using the lowest enzyme concentration (2.1 g/L) and the shortest hydrolysis time (60 min). By using US pre-treatment, on average, a 2.2 times higher FAA content could be achieved compared to traditional hydrolysis. Additionally, results for the kinetic parameters k_M and k_A confirmed the potential of applying US treatment before hydrolysis. The effect of CSL protein hydrolysate on plant growth was tested in vivo on wheat grain seed germination and resulted in the significant increase in germination parameters compared to the control treatment. These findings indicate that by-products of starch industry could be a promising source for the production of low-cost sustainable biostimulants. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Graphical abstract

17 pages, 6342 KiB

Open AccessArticle

Effects of Several Preharvest Canopy Applications on Yield and Quality of Table Grapes (Vitis vinifera L.) Cv. Crimson Seedless

by Despoina G. Petoumenou and Vasileios-Emmanouil Patris

Plants 2021, 10(5), 906; https://doi.org/10.3390/plants10050906 - 30 Apr 2021

Cited by 3 | Viewed by 3115

Abstract

Modern viticultural areas are being confronted with the negative impacts of global warming on yield and fruit composition, with especially adverse effects on anthocyanin synthesis. Novel and sustainable tools, such as biostimulants, may represent a viable alternative to traditional cultural practices, thus promoting [...] Read more.

Modern viticultural areas are being confronted with the negative impacts of global warming on yield and fruit composition, with especially adverse effects on anthocyanin synthesis. Novel and sustainable tools, such as biostimulants, may represent a viable alternative to traditional cultural practices, thus promoting eco-friendly strategies to enhance the yield, fruit quality and abiotic stress tolerance of grapevines. ‘Crimson Seedless’ is a late-season red table grape variety, and due to climatic warming, its berries are frequently failing to acquire the commercially acceptable red color. Canopy applications of different biostimulants, namely, Kelpak^®, Sunred^®, Cytolan^®, LalVigne™ Mature as well as Ethrel^® Top, were tested on grapevine cv. Crimson Seedless grown under semi-arid Mediterranean conditions in order to evaluate their effects on yield and fruit quality. Some of the products were sprayed in canopies at labeled doses, and some were applied at doses reported in other studies. For the control treatment, canopies were sprayed with water. Sampling started at veraison and was repeated at 10-day intervals to measure the evolution of berry weight, length and diameter, as well as the total soluble solids and titratable acidity of the juice. The grapes were harvested when the berries of one of the treatments attained the commercially acceptable color. The greatest improvements in the red berry color were achieved with Sunred^® (at a dose of 4 L ha⁻¹) and Ethrel^® Top (250 ppm plus glycerol at 1%), each applied at veraison and 10 days later. The different applications had varying effects on productivity and qualitative parameters. Only Sunred^® improved the accumulation of anthocyanin and the overall acceptability of table grapes by consumers. The obtained results clearly demonstrate that applying Sunred^® can improve the yield and qualitative parameters of the red table grape variety ‘Crimson Seedless’, indicating that this biostimulant could be a viable alternative to the most widely used plant growth regulator, ethephon. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

15 pages, 2696 KiB

Open AccessArticle

Seed Priming with Sorghum Water Extract Improves the Performance of Camelina (Camelina sativa (L.) Crantz.) under Salt Stress

by Ping Huang, Lili He, Adeel Abbas, Sadam Hussain, Saddam Hussain, Daolin Du, Muhammad Bilal Hafeez, Sidra Balooch, Noreen Zahra, Xiaolong Ren, Muhammad Rafiq and Muhammad Saqib

Plants 2021, 10(4), 749; https://doi.org/10.3390/plants10040749 - 12 Apr 2021

Cited by 40 | Viewed by 3786

Abstract

Seed priming with sorghum water extract (SWE) enhances crop tolerance to salinity stress; however, the application of SWE under salinity for camelina crop has not been documented so far. This study evaluated the potential role of seed priming with SWE in improving salt [...] Read more.

Seed priming with sorghum water extract (SWE) enhances crop tolerance to salinity stress; however, the application of SWE under salinity for camelina crop has not been documented so far. This study evaluated the potential role of seed priming with SWE in improving salt stress tolerance in camelina. Primed (with 5% SWE and distilled water-hydropriming) and nonprimed seeds were sown under control (no salt) and salt stress (10 dS m⁻¹) conditions. Salinity reduced camelina’s emergence and growth, while seed priming with SWE improved growth under control and stress conditions. Under salt stress, seed priming with SWE enhanced emergence percentage (96.98%), increased root length (82%), shoot length (32%), root dry weight (75%), shoot dry weight (33%), α-amylase activity (66.43%), chlorophyll content (60–92%), antioxidant enzymes activity (38–171%) and shoot K⁺ ion (60%) compared with nontreated plants. Similarly, under stress conditions, hydrogen peroxide, malondialdehyde (MDA) content, and shoot Na⁺ ion were reduced by 60, 31, and 40% by seed priming with SWE, respectively, over the nonprimed seeds. Therefore, seed priming with SWE may be used to enhance the tolerance against salt stress in camelina. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

17 pages, 2485 KiB

Open AccessArticle

Seedling Responses to Organically-Derived Plant Growth Promoters: An Effects-Based Approach

by Simon Hodge, Charles N. Merfield, Wendy Y. Y. Liu and Heng W. Tan

Plants 2021, 10(4), 660; https://doi.org/10.3390/plants10040660 - 30 Mar 2021

Cited by 4 | Viewed by 2493

Abstract

Organically-derived biofertilizers and biostimulants, developed from harvested materials such as seaweed and waste from animal and fish processing, are currently the subject of much fundamental and applied research. These products have significant potential in reducing synthetic fertilizer inputs to horticultural, arable, and pasture-based [...] Read more.

Organically-derived biofertilizers and biostimulants, developed from harvested materials such as seaweed and waste from animal and fish processing, are currently the subject of much fundamental and applied research. These products have significant potential in reducing synthetic fertilizer inputs to horticultural, arable, and pasture-based agricultural systems, although there is frequently some ambiguity over the magnitude and consistency of any positive effects these products may have on plant performance. This study examined the effects of organically-derived plant growth promoters (PGPs) available in New Zealand on the early vegetative growth of 16 plant species maintained under glasshouse conditions. When applied as a root drench to low nutrient potting mix, the effects of the PGPs on seedling shoot growth were strongly related to the NPK contents of the applied solutions. Any positive effects on shoot growth were, on average, reduced when the seedlings were maintained in higher nutrient growing media. Applying the PGPs at concentrations twice, and four times, the recommended concentration, only caused further growth responses when the PGPs contained high levels of nutrients. Applying the PGPs as a foliar spray had negligible effects on shoot growth. Overall, the results of these trials suggest that the positive effects of applying some organically-derived PGPs on seedling growth are a function of the PGP nutrient content, and not due to any indirect effects related to phytohormone pathways or modification of rhizosphere microorganisms. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

21 pages, 2241 KiB

Open AccessArticle

Glutacetine^® Biostimulant Applied on Wheat under Contrasting Field Conditions Improves Grain Number Leading to Better Yield, Upgrades N-Related Traits and Changes Grain Ionome

by Victor Maignan, Patrick Géliot and Jean-Christophe Avice

Plants 2021, 10(3), 456; https://doi.org/10.3390/plants10030456 - 28 Feb 2021

Cited by 7 | Viewed by 3845

Abstract

Wheat is one of the most important cereals for human nutrition, but nitrogen (N) losses during its cultivation cause economic problems and environmental risks. In order to improve N use efficiency (NUE), biostimulants are increasingly used. The present study aimed to evaluate the [...] Read more.

Wheat is one of the most important cereals for human nutrition, but nitrogen (N) losses during its cultivation cause economic problems and environmental risks. In order to improve N use efficiency (NUE), biostimulants are increasingly used. The present study aimed to evaluate the effects of Glutacetine^®, a biostimulant sprayed at 5 L ha⁻¹ in combination with fertilizers (urea or urea ammonium nitrate (UAN)), on N-related traits, grain yield components, and the grain quality of winter bread wheat grown at three field sites in Normandy (France). Glutacetine^® improved grain yield via a significant increase in the grain number per spike and per m², which also enhanced the thousand grain weight, especially with urea. The total N in grains and the NUE tended to increase in response to Glutacetine^®, irrespective of the site or the form of N fertilizer. Depending on the site, spraying Glutacetine^® can also induce changes in the grain ionome (analyzed by X-ray fluorescence), with a reduction in P content observed (site 2 under urea nutrition) or an increase in Mn content (site 3 under UAN nutrition). These results provide a roadmap for utilizing Glutacetine^® biostimulant to enhance wheat production and flour quality in a temperate climate. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

13 pages, 941 KiB

Open AccessArticle

Effects of Arthrospira platensis Extract on Physiology and Berry Traits in Vitis vinifera

by Linda Salvi, Alberto Niccolai, Eleonora Cataldo, Sofia Sbraci, Francesca Paoli, Paolo Storchi, Liliana Rodolfi, Mario R. Tredici and Giovan Battista Mattii

Plants 2020, 9(12), 1805; https://doi.org/10.3390/plants9121805 - 19 Dec 2020

Cited by 7 | Viewed by 2280

Abstract

Several advantages on physiology, productivity, and grape quality have been reported for grapevine treated with seaweed extracts, but little is known about the importance of cyanobacterial-based biostimulants in viticulture. The purpose of this pioneering work was to analyze the broad-spectrum effects of the [...] Read more.

Several advantages on physiology, productivity, and grape quality have been reported for grapevine treated with seaweed extracts, but little is known about the importance of cyanobacterial-based biostimulants in viticulture. The purpose of this pioneering work was to analyze the broad-spectrum effects of the Arthrospiraplatensis F&M-C256 extract on Vitis vinifera L. cv. Pinot Nero grown in pots in optimal conditions and under water stress. To evaluate the effects, major physiological parameters of the plants and the quali-quantitative parameters of grape were analyzed. According to the results obtained in this study, ameliorating effects in leaf gas exchanges induced by A. platensis F&M-C256 treatments were detected in both irrigation regimes. Above all, A. platensis F&M-C256 allowed keeping stomata open without negative consequences in water potential in treated vines under water-stress conditions. In terms of berry traits, A. platensis F&M-C256-treated vines presented higher berry weight in comparison with untreated vines in both water regimes and improved berry composition in treated vines subjected to drought. The results of the present study demonstrated an A. platensis-dependent physiological response in case of abiotic stress, which prominently affects grape traits at harvest. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

13 pages, 1280 KiB

Open AccessArticle

Impact of Seed Dressing and Soil Application of Potassium Humate on Cotton Plants Productivity and Fiber Quality

by Asmat Ullah, Muqarrab Ali, Khurram Shahzad, Fiaz Ahmad, Shahid Iqbal, Muhammad Habib Ur Rahman, Shakeel Ahmad, Muhammad Mazhar Iqbal, Subhan Danish, Shah Fahad, Jawaher Alkahtani, Mohamed Soliman Elshikh and Rahul Datta

Plants 2020, 9(11), 1444; https://doi.org/10.3390/plants9111444 - 26 Oct 2020

Cited by 34 | Viewed by 4882

Abstract

Humus is the stable form of added crop and animal residues. The organic matter after a long-term decomposition process converts into humic substances. The naturally occurring humus is present in less amount in soils of the arid and semi-arid regions. The addition of [...] Read more.

Humus is the stable form of added crop and animal residues. The organic matter after a long-term decomposition process converts into humic substances. The naturally occurring humus is present in less amount in soils of the arid and semi-arid regions. The addition of commercially available humic acid can, therefore, contribute to improving soil health and crop yields. The present study was conducted to evaluate the effect of potassium humate, applied through soil seed dressing, on cotton productivity and fiber quality attributes. Seed dressing with potassium humate was done at the rate of 0, 100, 150 and 200 mL kg⁻¹ seed while in soil potassium humate was applied at the rate of 0, 10, 20 and 30 L ha⁻¹. Results showed that the combined application of potassium humate by seed dressing and through soil application improved the soil properties, productivity and fiber quality traits of cotton. All levels of soil applied potassium humate (10, 20 and 30 L ha⁻¹) performed better over seed dressing in terms of cotton productivity and fiber quality attributes. Among the soil application rates, 20 L ha⁻¹ potassium humate proved better as compared to other rates (0, 10 and 30 L ha⁻¹). Higher soil application of potassium humate (30 L ha⁻¹) showed depressing effects on all the traits studied like the reduction of 12.4% and 6.6% in Ginning out turn and fiber length, respectively, at a seeding dressing of 200 mL kg⁻¹. In conclusion, potassium humate seed dressing and soil application at the rate of 200 mL kg⁻¹ and 20 L ha⁻¹, respectively, is a better approach to improve cotton productivity. Soil potassium humate should not exceed a rate of 20 L ha⁻¹ when the seed dressing of potassium is also practiced. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Graphical abstract

19 pages, 1174 KiB

Open AccessEditor’s ChoiceArticle

Transcriptome Analyses and Antioxidant Activity Profiling Reveal the Role of a Lignin-Derived Biostimulant Seed Treatment in Enhancing Heat Stress Tolerance in Soybean

by Cristina Campobenedetto, Giuseppe Mannino, Chiara Agliassa, Alberto Acquadro, Valeria Contartese, Christian Garabello and Cinzia Margherita Bertea

Plants 2020, 9(10), 1308; https://doi.org/10.3390/plants9101308 - 02 Oct 2020

Cited by 40 | Viewed by 5154

Abstract

Soybean (Glycine max Merr.) is a worldwide important legume crop, whose growth and yield are negatively affected by heat stress at germination time. Here, we tested the role of a biostimulant based on lignin derivatives, plant-derived amino acids, and molybdenum in enhancing [...] Read more.

Soybean (Glycine max Merr.) is a worldwide important legume crop, whose growth and yield are negatively affected by heat stress at germination time. Here, we tested the role of a biostimulant based on lignin derivatives, plant-derived amino acids, and molybdenum in enhancing soybean heat stress tolerance when applied on seeds. After treatment with the biostimulant at 35 °C, the seed biometric parameters were positively influenced after 24 h, meanwhile, germination percentage was increased after 72 h (+10%). RNA-Seq analyses revealed a modulation of 879 genes (51 upregulated and 828 downregulated) in biostimulant-treated seeds as compared with the control, at 24 h after incubation at 35 °C. Surprisingly, more than 33% of upregulated genes encoded for ribosomal RNA (rRNA) methyltransferases and proteins involved in the ribosome assembly, acting in a specific protein network. Conversely, the downregulated genes were involved in stress response, hormone signaling, and primary metabolism. Finally, from a biochemical point of view, the dramatic H₂O₂ reduction 40%) correlated to a strong increase in non-protein thiols (+150%), suggested a lower oxidative stress level in biostimulant-treated seeds, at 24 h after incubation at 35 °C. Our results provide insights on the biostimulant mechanism of action and on its application for seed treatments to improve heat stress tolerance during germination. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

14 pages, 7483 KiB

Open AccessArticle

Substrate and Plant Genotype Strongly Influence the Growth and Gene Expression Response to Trichoderma afroharzianum T22 in Sugar Beet

by John Schmidt, Bradley R. Dotson, Ludwig Schmiderer, Adriaan van Tour, Banushree Kumar, Salla Marttila, Kenneth M. Fredlund, Susanne Widell and Allan G. Rasmusson

Plants 2020, 9(8), 1005; https://doi.org/10.3390/plants9081005 - 07 Aug 2020

Cited by 10 | Viewed by 3820

Abstract

Many strains of Trichoderma fungi have beneficial effects on plant growth and pathogen control, but little is known about the importance of plant genotype, nor the underlying mechanisms. We aimed to determine the effect of sugar beet genotypic variation on Trichoderma biostimulation. The [...] Read more.

Many strains of Trichoderma fungi have beneficial effects on plant growth and pathogen control, but little is known about the importance of plant genotype, nor the underlying mechanisms. We aimed to determine the effect of sugar beet genotypic variation on Trichoderma biostimulation. The effect of Trichoderma afroharzianum T22 on sugar beet inbred genotypes were investigated in soil and on sterile agar medium regarding plant growth, and by quantitative reverse transcriptase-linked polymerase chain reaction (qRT-PCR) analysis for gene expression. In soil, T22 application induced up to 30% increase or decrease in biomass, depending on plant genotype. In contrast, T22 treatment of sterile-grown seedlings resulted in a general decrease in fresh weight and root length across all sugar beet genotypes. Root colonization of T22 did not vary between the sugar beet genotypes. Sand- and sterile-grown roots were investigated by qRT-PCR for expression of marker genes for pathogen response pathways. Genotype-dependent effects of T22 on, especially, the jasmonic acid/ethylene expression marker PR3 were observed, and the effects were further dependent on the growth system used. Thus, both growth substrate and sugar beet genotype strongly affect the outcome of inoculation with T. afroharzianum T22. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Graphical abstract

16 pages, 2745 KiB

Open AccessArticle

Comparison of Biostimulant Treatments in Acmella oleracea Cultivation for Alkylamides Production

by Stefania Sut, Irene Ferrarese, Shyam Sharan Shrestha, Gourav Kumar, Antonio Slaviero, Simone Sello, Adriano Altissimo, Luca Pagni, Francesco Gattesco and Stefano Dall’Acqua

Plants 2020, 9(7), 818; https://doi.org/10.3390/plants9070818 - 29 Jun 2020

Cited by 11 | Viewed by 3573

Abstract

Acmella oleracea is a promising cosmetic, nutraceutical, and pharmaceutical ingredient, and plants with high levels of active compounds are needed in the market. Cultivation can be valuable if sufficient levels of alkylamides are present in plant material. In this regard the application of [...] Read more.

Acmella oleracea is a promising cosmetic, nutraceutical, and pharmaceutical ingredient, and plants with high levels of active compounds are needed in the market. Cultivation can be valuable if sufficient levels of alkylamides are present in plant material. In this regard the application of biostimulants can be an innovative approach to increase yield of cultivation or bioactive compound levels. A. oleracea plants were cultivated in Northern Italy in an experimental site using three different types of biostimulants, triacontanol-based mixture (Tria), an extract from plant tissues (LL017), and seaweed extract (Swe). Plants were grown in the field in two different growing seasons (2018 and 2019). After treatments inflorescences were harvested and the quali-quantitative analysis of alkylamides and polyphenols was performed. Treated and control plants were compared for yields, morphometric measurements, quali-quantitative composition in secondary metabolites. Overall results show that both triacontanol-based mixture and the LL017 positively influenced plant growth (Tria >+ 22%; LL017 >+ 25%) and flower production (Tria >+ 34%; LL017 >+ 56%). The amount of alkylamides and polyphenols in flowers were between 2.0–5.2% and 0.03–0.50%, respectively. Biostimulant treatments ensure higher cultivation yields and allow maintenance of the alkylamide and polyphenol levels based on % (w/w), thus offering an advantage in the final quantity of extractable chemicals. Furthermore, data revealed that samples harvested in late season show a decrease of polyphenols. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Graphical abstract

12 pages, 1543 KiB

Open AccessArticle

Foliar Application of an Amino Acid-Enriched Urea Fertilizer on ‘Greco’ Grapevines at Full Veraison Increases Berry Yeast-Assimilable Nitrogen Content

by Alessandro Mataffo, Pasquale Scognamiglio, Antonio Dente, Daniela Strollo, Giuseppe Colla, Youssef Rouphael and Boris Basile

Plants 2020, 9(5), 619; https://doi.org/10.3390/plants9050619 - 13 May 2020

Cited by 13 | Viewed by 3286

Abstract

Reaching a sufficient yeast assimilable nitrogen (YAN) content in berries at harvest is considered a main viticultural goal for wine-making, because low YANs can slow down must fermentation and have negative effects on wine sensory attributes. For this reason, many attempts have been [...] Read more.

Reaching a sufficient yeast assimilable nitrogen (YAN) content in berries at harvest is considered a main viticultural goal for wine-making, because low YANs can slow down must fermentation and have negative effects on wine sensory attributes. For this reason, many attempts have been made to define correct fertilization strategies to stimulate YAN accumulation in the berries. Foliar application of amino acid-enriched urea fertilizer is considered a promising environmentally friendly strategy for improving the yield and nutrient efficiency of plants. The aim of this two-year research was to study the effects of two fertilizers based on urea enriched with amino acids applied at low doses in diverse phenological stages on berry YAN concentration in ‘Greco’ grapevines. The results of this study indicate that amino acid-enriched urea fertilizers induced an increase in YANs in the ‘Greco’ berries at harvest, but only when the application was undertaken at full veraison. Foliar applications applied at veraison onset or post-veraison appeared to be ineffective. In addition, the fertilizers enhanced YAN accumulation in the berry without modifying the other composition parameters measured in this study (total soluble solids, titratable acidity, pH and malic acid). Therefore, the results of our study suggest that foliar application of urea fertilizers enriched with amino acids is an effective strategy to increase yeast-assimilable nitrogen concentration in grapevine berries at harvest. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

11 pages, 1009 KiB

Open AccessArticle

Activation of Early Defense Signals in Seedlings of Nicotiana benthamiana Treated with Chitin Nanoparticles

by Miguel López, Elisa Miranda, Cecilia Ramos, Héctor García and Andrónico Neira-Carrillo

Plants 2020, 9(5), 607; https://doi.org/10.3390/plants9050607 - 10 May 2020

Cited by 6 | Viewed by 2713

Abstract

Chitin is an excellent material for the synthesis of nanoparticles because it is an elicitor and can form nanostructured materials. The application of chitin nanoparticles (CNPs) in plants can activate early defense responses associated with chitin. In this study, CNPs were synthesized by [...] Read more.

Chitin is an excellent material for the synthesis of nanoparticles because it is an elicitor and can form nanostructured materials. The application of chitin nanoparticles (CNPs) in plants can activate early defense responses associated with chitin. In this study, CNPs were synthesized by water in oil (W/O) emulsion using an aqueous chitin solution. The CNPs were characterized and used to evaluate the activation of genes related to early responses to chitin and the production of reactive oxygen species (ROS) on seedlings of Nicotiana benthamiana. The CNPs had an average size of 280 nm in diameter, a polydispersity of 0.299, a surface charge of 26.9 mV, and their chemical composition was corroborated by the disappearance of microaggregated CNPs treated with chitinases observed under a microscope. Seedlings treated with CNPs for one hour revealed increments in the expression of genes STZ, ATL2, and MAPK3, in contrast when they were treated with chitin oligomers, and no changes in gene CERK1 was detected in both conditions. Finally, the synthesis of ROS mediated by CNPs was detected in seedlings, which was higher than those generated by the treatment of chitin oligomers. These results demonstrated the capability to generate CNPs by emulsion, which are capable of triggering responses related to early defense in N. benthamiana more efficiently than chitin oligomers. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

19 pages, 2169 KiB

Open AccessEditor’s ChoiceArticle

Phenylalanine and Tyrosine as Exogenous Precursors of Wheat (Triticum aestivum L.) Secondary Metabolism through PAL-Associated Pathways

by Pavel Feduraev, Liubov Skrypnik, Anastasiia Riabova, Artem Pungin, Elina Tokupova, Pavel Maslennikov and Galina Chupakhina

Plants 2020, 9(4), 476; https://doi.org/10.3390/plants9040476 - 09 Apr 2020

Cited by 75 | Viewed by 8758

Abstract

Reacting to environmental exposure, most higher plants activate secondary metabolic pathways, such as the metabolism of phenylpropanoids. This pathway results in the formation of lignin, one of the most important polymers of the plant cell, as well as a wide range of phenolic [...] Read more.

Reacting to environmental exposure, most higher plants activate secondary metabolic pathways, such as the metabolism of phenylpropanoids. This pathway results in the formation of lignin, one of the most important polymers of the plant cell, as well as a wide range of phenolic secondary metabolites. Aromatic amino acids, such as phenylalanine and tyrosine, largely stimulate this process, determining two ways of lignification in plant tissues, varying in their efficiency. The current study analyzed the effect of phenylalanine and tyrosine, involved in plant metabolism through the phenylalanine ammonia-lyase (PAL) pathway, on the synthesis and accumulation of phenolic compounds, as well as lignin by means of the expression of a number of genes responsible for its biosynthesis, based on the example of common wheat (Triticum aestivum L.). Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Graphical abstract

Review

Jump to: Research

25 pages, 1404 KiB

Open AccessEditor’s ChoiceReview

Microbial Biostimulants as Response to Modern Agriculture Needs: Composition, Role and Application of These Innovative Products

by Adele M. Castiglione, Giuseppe Mannino, Valeria Contartese, Cinzia M. Bertea and Andrea Ertani

Plants 2021, 10(8), 1533; https://doi.org/10.3390/plants10081533 - 27 Jul 2021

Cited by 61 | Viewed by 9134

Abstract

An increasing need for a more sustainable agriculturally-productive system is required in order to preserve soil fertility and reduce soil biodiversity loss. Microbial biostimulants are innovative technologies able to ensure agricultural yield with high nutritional values, overcoming the negative effects derived from environmental [...] Read more.

An increasing need for a more sustainable agriculturally-productive system is required in order to preserve soil fertility and reduce soil biodiversity loss. Microbial biostimulants are innovative technologies able to ensure agricultural yield with high nutritional values, overcoming the negative effects derived from environmental changes. The aim of this review was to provide an overview on the research related to plant growth promoting microorganisms (PGPMs) used alone, in consortium, or in combination with organic matrices such as plant biostimulants (PBs). Moreover, the effectiveness and the role of microbial biostimulants as a biological tool to improve fruit quality and limit soil degradation is discussed. Finally, the increased use of these products requires the achievement of an accurate selection of beneficial microorganisms and consortia, and the ability to prepare for future agriculture challenges. Hence, the implementation of the microorganism positive list provided by EU (2019/1009), is desirable. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

17 pages, 337 KiB

Open AccessEditor’s ChoiceReview

The Role of Microbial Inoculants on Plant Protection, Growth Stimulation, and Crop Productivity of the Olive Tree (Olea europea L.)

by Georgios Bizos, Efimia M. Papatheodorou, Theocharis Chatzistathis, Nikoletta Ntalli, Vassilis G. Aschonitis and Nikolaos Monokrousos

Plants 2020, 9(6), 743; https://doi.org/10.3390/plants9060743 - 12 Jun 2020

Cited by 44 | Viewed by 6380

Abstract

The olive tree (Olea europaea L.) is an emblematic, long-living fruit tree species of profound economic and environmental importance. This study is a literature review of articles published during the last 10 years about the role of beneficial microbes [Arbuscular Mycorrhizal Fungi [...] Read more.

The olive tree (Olea europaea L.) is an emblematic, long-living fruit tree species of profound economic and environmental importance. This study is a literature review of articles published during the last 10 years about the role of beneficial microbes [Arbuscular Mycorrhizal Fungi (AMF), Plant Growth Promoting Rhizobacteria (PGPR), Plant Growth Promoting Fungi (PGPF), and Endophytes] on olive tree plant growth and productivity, pathogen control, and alleviation from abiotic stress. The majority of the studies examined the AMF effect using mostly Rhizophagus irregularis and Glomus mosseae species. These AMF species stimulate the root growth improving the resistance of olive plants to environmental and transplantation stresses. Among the PGPR, the nitrogen-fixing bacteria Azospirillum sp. and potassium- and phosphorous-solubilizing Bacillus sp. species were studied extensively. These PGPR species were combined with proper cultural practices and improved considerably olive plant’s growth. The endophytic bacterial species Pseudomonas fluorescens and Bacillus sp., as well as the fungal species Trichoderma sp. were identified as the most effective biocontrol agents against olive tree diseases (e.g., Verticillium wilt, root rot, and anthracnose). Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Graphical abstract

13 pages, 770 KiB

Open AccessReview

Potential of Karrikins as Novel Plant Growth Regulators in Agriculture

by Michal Antala, Oksana Sytar, Anshu Rastogi and Marian Brestic

Plants 2020, 9(1), 43; https://doi.org/10.3390/plants9010043 - 26 Dec 2019

Cited by 24 | Viewed by 8365

Abstract

Karrikins (KARs) have been identified as molecules derived from plant material smoke, which have the capacity to enhance seed germination for a wide range of plant species. However, KARs were observed to not only impact seed germination but also observed to influence several [...] Read more.

Karrikins (KARs) have been identified as molecules derived from plant material smoke, which have the capacity to enhance seed germination for a wide range of plant species. However, KARs were observed to not only impact seed germination but also observed to influence several biological processes. The plants defected in the KARs signaling pathway were observed to grow differently with several morphological changes. The observation of KARs as a growth regulator in plants leads to the search for an endogenous KAR-like molecule. Due to its simple genomic structure, Arabidopsis (Arabidopsis thaliana L.) helps to understand the signaling mechanism of KARs and phenotypic responses caused by them. However, different species have a different phenotypic response to KARs treatment. Therefore, in the current work, updated information about the KARs effect is presented. Results of research on agricultural and horticultural crops are summarized and compared with the findings of Arabidopsis studies. In this article, we suggested that KARs may be more important in coping with modern problems than one could imagine. Full article

(This article belongs to the Special Issue Biostimulants in Plants Science)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Biostimulants in Plants Science

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Published Papers (18 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI