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Article

Effects of Seed Priming with Talaromyces ruber Extracts on Tomato (Solanum lycopersicum) Growth

by
Álvaro Iglesias-Ganado
1,2,
Jorge Poveda
1,2,
Oscar Santamaría
1,2,
Sara Rodrigo
3,
María I. Pozo
1,4 and
Jorge Martín-García
1,2,*
1
Recognized Research Group Agrobiotech, UIC-370 (JCyL), Higher Technical School of Agricultural Engineering of Palencia, University of Valladolid, 34004 Palencia, Spain
2
Department of Plant Production and Forest Resources, University Institute for Research in Sustainable Forest Management (iuFOR), University of Valladolid, Avda. Madrid 57, 34004 Palencia, Spain
3
Dehesa Research Institute (INDEHESA), University of Extremadura, Badajoz, Avda. Elvas s/n, 06006 Badajoz, Spain
4
Department of Agroforestal Sciences, University of Valladolid, Avda. Madrid 57, 34004 Palencia, Spain
*
Author to whom correspondence should be addressed.
Agriculture 2025, 15(17), 1868; https://doi.org/10.3390/agriculture15171868
Submission received: 4 July 2025 / Revised: 22 August 2025 / Accepted: 28 August 2025 / Published: 31 August 2025
(This article belongs to the Special Issue Advanced Cultivation Technologies for Horticultural Crops Production)
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Abstract

Modern agriculture requires effective and sustainable tools to enhance crop performance while minimizing the environmental impact. In this context, the application of fungal-derived bioactive compounds directly onto seeds represents a promising alternative. In this study, tomato seeds (Solanum lycopersicum) were subjected to mycopriming treatment using two fungal extracts obtained from the mycelium and culture filtrate of Talaromyces ruber. Two independent greenhouse trials were conducted to assess germination dynamics, morphometric traits, and physiological parameters (chlorophyll content, flavonol index, and anthocyanin index). Although germination rates were not significantly affected, root development was consistently enhanced by the treatments compared with the control group in both experiments. In contrast, no clear improvement was observed in shoot growth or leaf physiological parameters. Overall, the application of T. ruber extracts via seed priming proved to be a feasible strategy to stimulate early-stage root development in tomatoes, potentially contributing to improved seedling vigor and agronomic performance. These findings support the potential use of fungal extracts as practical tools for improving seedling quality in commercial nursery production.

1. Introduction

Modern agriculture faces the complex challenge of, on the one hand, maintaining the levels of quality required by the market yet responding to the rapidly growing global food demand [1]. On the other hand, the environment poses additional pressures [2] and threats that are magnified by ongoing climatic change [3]. Given these challenges, the scientific community and the agri-food sector are seeking innovative strategies that can maintain or improve crop productivity without compromising environmental sustainability [4].
One of the most valuable crops affected by these constraints is the tomato, the world’s most widely cultivated vegetable, with 5.4 million hectares of cultivated area and a global production of 192 million tons [5]. This crop faces global agricultural challenges, along with specific threats such as the proliferation of diseases caused by fungi, bacteria, nematodes, and viruses [6], possibly driven by the intensification of agricultural systems [7]. These biotic stresses are further aggravated by abiotic factors, including extreme summer temperatures that negatively affect tomato growth and fruit quality [8]. Moreover, soil salinity, caused by irrigation with saline water, reduces the plant’s ability to absorb water and nutrients, ultimately leading to reduced plant growth and yield [9]. Altogether, these conditions may compromise the sustainability of tomato cultivation in traditional production areas, potentially leading to significant economic losses [10].
In this worrisome scenario, improving plant fitness during the early stages of development, particularly while seedlings are still in the horticultural nursery, might relieve most of the current production threats listed above. The rationale behind this improvement is that more vigorous plants may exhibit greater tolerance to the previously described biotic and abiotic stresses once they leave the protection of the nursery to be transplanted in the field [11]. There are, however, several biotechnological strategies that might be applied to plant reproductive material to improve plant development in the early stages. Among these strategies, seed priming stands out in terms of novelty. It consists of a pre-sowing treatment in which seeds are partially hydrated to activate metabolic processes prior to germination, with the primary goal of enhancing germination performance and seedling establishment, ultimately contributing to improved crop productivity [12].
Seed priming can be amended by using plant growth-promoting microorganisms (PGPMs) [13]. When fungi are used, the technique is referred to as mycopriming [14]. However, the application of PGPMs in agriculture remains challenging under realistic field conditions. Inconclusive field trials occur sometimes due to the difficulty to control external variables that affect the establishment of microorganisms in the soil or in the plant, and, therefore, the expected benefits are not consistently observed [15]. Another issue associated with the direct inoculation of living microorganisms is their interaction with the pre-existing microbiome in the environment. In certain cases, introduced microorganisms alter the structure and composition of soil or rhizosphere microbial communities, displacing beneficial species or disrupting key ecological functions [16,17]. Additionally, some endophytic fungi may express pathogenicity in crops [18], and their capacity to cause infections in humans has also been documented [19]. All these issues have led regulators, such as those in the European Union, to impose strict controls on the use of microorganisms in agriculture [20,21,22].
It has been demonstrated that the beneficial effects of PGPMs are often attributed to the production of a series of secondary metabolites [23]. Secondary metabolites (SMs) are bioactive organic compounds not directly involved in the microorganism’s primary metabolism but that play crucial roles in the interaction of the plant subject with its environment, e.g., by affecting plant–microbe interactions, enhancing stress tolerance, or providing protection against pathogens [24]. These compounds can be produced under laboratory conditions by extracting them from a fungal culture grown in a nutrient medium. Consequently, an alternative approach to mycopriming could involve the in vitro production of these bioactive compounds and their direct application to seeds [25].
The application of fungal extracts and, in particular, SMs, from endophytic fungi has been mainly explored via foliar spraying [26], but the main practical and economical limitation of this method is the large quantity of extract that is required [25]. In contrast, their application as a seed treatment has not been extensively investigated, but it represents a promising approach. This is particularly relevant in crops like the tomato, where the small size of the seeds allows a large number of them to be treated with a minimal amount of bioactive compounds, making this technique both economically and technically feasible [27].
The mycopriming technique using SMs extracted from endophytic fungi has been tested successfully as a plant growth promoter. This technique involves soaking seeds in a solution containing SMs produced by fungi. Through this process, the seeds absorb these compounds, which can produce beneficial effects on germination and early development [28]. Extracts from endophytic fungi have been shown to improve germination rates in various species [29,30] and have also been successful in enhancing early growth in several crops [31,32]. There is, however, wide variation in the production of bioactive compounds among fungal taxa. The genus Talaromyces stands out as a producer of bioactive compounds with potential interest in agriculture, including indole-3-acetic acid (IAA), phosphate-solubilizing metabolites, siderophores, and lytic enzymes, such as chitinases and β-glucanases, which contribute to plant growth promotion and biocontrol activity [33,34,35]. Within the genus, Talaromyces ruber—a species previously classified as Penicillium rubrum [36]—is a proven source of agriculturally relevant bioactive metabolites such as Rubratoxin B [37].
The aim of this study was to evaluate the PGP effect of seed treatments using extracts obtained from the endophytic fungus T. ruber on tomato seedlings during their early developmental stages. The hypothesis is that enhancing seedling fitness during these stages may increase their tolerance to various biotic and abiotic stresses encountered throughout the crop cycle which should be confirmed in future trials. This approach could provide a sustainable, fully organic solution for seed producers and nurseries to increase the value of their products, aligning with current agricultural policies that promote the use of environmentally friendly inputs.

2. Materials and Methods

2.1. Fungal and Plant Material

The endophyte T. ruber strain EN3 belongs to the microbial collection of the GIR AGROBIOTECH (Palencia, Spain). The taxonomic identity of the fungal isolate T. ruber EN3 was identified by sequencing the EF1α and ITS regions. The isolate was routinely cultured onto potato dextrose agar plates (PDA, Scharlab, Spain) and incubated in dark conditions at 25 °C for 7 days. For long-term preservation, cultures were stored at 4 °C and periodically subcultured to maintain viability.
Commercial seeds of tomatoes (S. lycopersicum), cultivar Optima F1, were supplied by Seminis (Oxnard, CA, USA). The seeds were kept in heat-sealed multilayer aluminum foil pouches designed to safeguard the viability of the seeds during storage, protecting them against moisture, light, and oxygen. Seeds were stored at 4 °C until use. All experimental procedures were performed in 2025.

2.2. Obtaining Fungal Extracts from T. ruber

Four 5 mm mycelial disks were excised from an actively growing colony of T. ruber on potato dextrose agar (PDA, Scharlab) and used to inoculate 400 mL of potato dextrose broth (PDB, Scharlab) in 500 mL Erlenmeyer flasks. The flasks were kept at room temperature (20–25 °C), in darkness, and shaken at 140 rpm using an orbital shaker (Edmund Bühler KS-15, Bodelshausen, Germany). During incubation, glucose concentration in each flask was measured daily using semi-quantitative rapid test strips with a detection range of 50–2000 mg·L−1 (Quantofix®, Macherey-Nagel, Düren, Germany). When glucose was nearly depleted (<100 mg·L−1), the extraction of SMs was carried out.
Two different sources were used for the extraction: the liquid filtrate and the mycelium, in order to recover a wider range of metabolites. For the extraction, the method described by García-LaTorre [28] was followed. The fungal culture was gravity-filtered using a qualitative filter, pore size 10–12 µm (Prat Dumas), to separate the mycelium from the liquid filtrate. The filtered solution was mixed with an equal volume of ethyl acetate 99.8% GLR (ETAC-POP-5K0, Labkem, Barcelona, Spain) in a separation funnel and shaken for 2 min. Once phase separation was complete, the aqueous phase was discarded. To remove residual water, sodium sulfate anhydrous EPR Reag. (SOSU-00T-1K0, Labkem, Barcelona, Spain) was added to the ethyl acetate phase, and the same filters used previously were employed to remove sodium sulfate residues. The organic solvent phase was then evaporated using a rotary evaporator (BUCHI R-80, Flawil, Switzerland). The resulting crude extract was resuspended in methanol 99.8% GLR (MTOL-POP-1K0, Labkem, Barcelona, Spain) and concentrated using a vial evaporator (DNA 120 Speed Vac, Eppendorf, Hamburg, Germany). Finally, to quantify the amount of fungal extract obtained, the empty vials were first weighed and subsequently reweighed after the evaporation process in the SpeedVac using a four-decimal precision analytical balance. The final volume was then adjusted with sterile water to obtain a concentration of 1 mg/L.
The mycelial part was mixed with acetone 99.6% GLR (ACET-POP-1K0, Labkem, Barcelona, Spain) and submerged in an ultrasonic bath at 40 °C and 35 kHz for 10 min to separate the metabolites from the mycelium. The content was subsequently filtered again using qualitative filters with a pore size of 10–12 µm, and the acetone was evaporated with a rotary evaporator. The resulting solid was resuspended in 50 mL of distilled water and mixed with an equal volume of ethyl acetate. From this point, the same extraction steps described above for the filtrate were followed, including the aqueous phase removal, drying with sodium sulfate, filtration, ethyl acetate evaporation, and methanol resuspension (Figure 1).

2.3. Seed Treatment

Seeds were surface sterilized by immersion in 70% ethanol for 1 min, followed by immersion in 2% sodium hypochlorite for 1 min. They were then rinsed three times with sterile distilled water.
SMs were resuspended in a 2.5% (v/v) dimethyl sulfoxide (DMSO; Thermo Fisher Scientific, Waltham, MA, USA) solution prepared with sterile distilled water, due to the high compatibility of DMSO with plant tissues [38]. The fungal extract suspensions were adjusted to a final concentration of 1 mg mL−1. The same protocol was applied to both the culture filtrate and the mycelium extracts.
A 2.5% DMSO solution (without SMs) was used as the control to account for any effects of the solvent itself. Tomato seeds were soaked in the treatment solutions for 12 h at room temperature under continuous shaking using an orbital shaker to ensure the uniform uptake of metabolites by the seed tissues. After soaking, the seeds were dried on sterile filter paper for 24 h in a laminar flow hood to maintain sterile conditions (Figure 2).

2.4. In Plant Experiments

The effect of the T. ruber extracts obtained from both the filtrate and the mycelium was evaluated in two independent greenhouse trials conducted twice under the same methodological conditions (greenhouse temperatures ranged between 15 °C and 25 °C). Tomato seeds primed with extracts were sown in pots (44 × 54 × 49 mm) in seed trays and placed in a greenhouse. Twenty-four biological replicates for each treatment were used with a total of three treatments evaluated. The substrate used was Terrahum (Klassman-Deilmann, Geeste, Germany) with an organic matter = 90%, electrical conductivity (EC) = 0.4 dS m−1, and pH = 5.5–6.5. Irrigation was applied weekly to maintain the substrate at field capacity, and no nutrient solution was added during the experiment. The greenhouse was equipped with an automatic temperature control system that maintained conditions with a minimum of 15 °C and a maximum of 25 °C. Additionally, artificial lighting (estimated photosynthetic photon flux density, PPFD, of 200–300 μmol·m−2·s−1) was used and regulated to provide a 16 h photoperiod. The climatic data of humidity, temperature, and radiation recorded in the greenhouse are shown in Table S1.

2.5. Morphometric and Physiological Characteristics Analyzed

Seedling emergence was monitored daily to determine the germination rate and to evaluate whether the treatments had any effect on the timing of emergence. Shoot length was measured at 14, 21, 28, 35, and 42 Days After Sowing (DAS), corresponding to BBCH stages 09, 10, 11, 12, and 13 in the first trial and 09, 10, 11, 13, and 14 in the second trial, according to the BBCH scale for tomatoes [39]. Shoot length was recorded from the substrate surface to the insertion point of the last visible leaf. At 42 DAS, the experiment was concluded, and root length, shoot dry weight, and root dry weight were measured.
Additionally, at 42 DAS, chlorophyll content, flavonol index, and anthocyanin index were measured using a portable multiparameter optical sensor Dualex-4 (Dualex Scientific+™ Polyphenol & Chlorophyll Meter, FORCE-A, Orsay, France). This device is equipped with a leaf clip that enables non-destructive measurements to be taken directly from the plant. To standardize the results, measurements were conducted on the last fully expanded leaf. All measurements were carried out in blocks to minimize potential errors, as the sensor is highly sensitive to environmental conditions, such as solar radiation and humidity, which may vary over time.

2.6. Statistical Analysis

A Kaplan–Meier survival analysis was applied to assess differences in germination dynamics among treatments. Survival curves were generated in R software (version 4.4.0, R Core Team, Vienna, Austria) using the Survfit function from the “Survival” package [40]. Differences among treatments were evaluated using the log-rank test applied to Kaplan–Meier germination curves. A one-way analysis of variance (ANOVA) was performed to evaluate the effects of treatments on plant height, biomass, and physiological parameters. When significant differences were detected, Tukey’s test (HSD) was used for multiple comparisons at a 95% confidence level (p < 0.05). The assumptions of normality and homogeneity of variances were verified using the Shapiro–Wilk and Bartlett tests, respectively. All statistical analyses were performed using R software environment (R Foundation for Statistical Computing, Vienna, Austria).

3. Results

3.1. Effect of the Seed Treatments on Germination Rates

In all treatments, seedling emergence was mostly concentrated between days 5 and 9. The survival curves did not reveal significant differences among treatments neither in the first trial (χ2 = 2.784; p = 0.25) nor in the second (χ2 = 4.753; p = 0.093).

3.2. Effect of the Seed Treatments on the Morphometric and Physiological Characteristics Analyzed

To gain deeper insight into the PGP potential of the treatments, the analysis was extended to shoot and root development parameters during the seedling stage. Weekly measurements of the shoot length were conducted. During the first three assessments, no statistically significant differences were observed among treatments in either trial (Table 1). However, in the first trial, the seeds primed with mycelium extracts showed a significant increase in shoot length during weeks 5 and 6 compared with the control, an effect that could not be replicated in the second trial (Figure 3). Significant differences in the shoot dry weight were also detected among treatments (Table 1), and the use of filtrate extract led to a significant improvement relative to the control (Figure 4). Regarding root traits, both the length and dry weight showed significant variation among treatments in both trials (Table 1). Seedlings derived from seeds treated with both types of extract (the first derived from the filtrate and the second from the mycelium extract) developed longer roots than the control treatment. In terms of root biomass, both treatments produced significant increases in the first trial (Figure 5), while in the second trial, only the mycelium extract remained effective (Figure 6). No significant differences were observed in the chlorophyll content, flavonol index, or anthocyanin index among treatments (Table 1). This indicates that the application of T. ruber extracts did not affect these physiological parameters in the aerial part of the seedlings, at least in the variables measured and within the duration of the experiment (Table S2).

4. Discussion

We evaluated the potential plant growth-promoting effects of extracts derived from the mycelium and liquid filtrate of T. ruber, obtained through organic solvent extraction and rotary evaporation. The extracts were applied to tomato seeds via mycopriming, and the effects were subsequently assessed in seedlings grown under controlled greenhouse conditions.
The Kaplan–Meier survival curves showed no statistically significant differences in germination rates. The use of high-quality certified seeds with a naturally high germination rate may have masked the potential beneficial effects of the treatments. Therefore, we could not confirm the positive influence reported in previous studies for seed priming with fungal extracts [29,30,41]. It is worth noting, however, that no signs of germination inhibition were observed in our trial, in contrast to previous findings that reported negative effects on the germination percentage [42,43].
We were interested in exploring treatment effects that lay beyond germination. Therefore, we analyzed the morphological traits of seedlings. In the first trial, the shoot length at 35 and 42 DAS was significantly increased by the mycelium treatment. This effect was not observed in the second trial, suggesting that the response to this treatment may vary under different conditions. The final measurements revealed the most pronounced outcomes. Focusing on the shoot, the increase in biomass observed in both treatments remained a trend that did not reach statistical significance. The consistency of the numerical increase across replicates may suggest that we should not rule out the possibility of a Type II statistical error. The greater shoot elongation observed in this second trial may have led to biomass dilution, potentially attenuating differences in the dry weight. It should be noted that improvements in root development do not necessarily lead to increases in shoot length or shoot dry weight, as previously reported in tomatoes [44,45]. This lack of correlation arises from the fact that they are generally governed by different physiological mechanisms. While shoot elongation is mainly driven by cell expansion, which is controlled by phytohormones such as auxins and gibberellins [46,47], shoot dry weight reflects the net accumulation of biomass, resulting from the balance between photosynthetic activity and assimilate allocation [48,49]. Consequently, these two parameters may respond differently to treatments. This distinction aligns with the results observed in the present study, where different treatments had varying effects on elongation and biomass accumulation. The results of this experiment are consistent with previous studies reporting improvements in the shoot length and biomass using similar techniques to those employed in this study, such as the application of Aspergillus fumigatus extracts in Glycine max [30], Epicoccum sorghinum extracts in tomatoes [50], or Aspergillus niger extracts in various Vigna species [51].
The most promising results of this trial were observed in the root system, as both the mycelium and filtrate treatments significantly improved the root length and root dry weight compared to the control. These findings are consistent with previous studies that also reported enhanced root development following fungal-based seed treatments, with comparable results in tomatoes using extracts of Alternaria leptinellae [28] or Glutamicibacter halophytocota [28,52], as well as in other crops such as the Vigna species with Aspergillus niger [51] or Pennisetum glaucum [53] with various species of Trichoderma. While the use of SMs extracted from the genus Talaromyces for seed treatment had not been studied so far, the direct inoculation of seeds with Talaromyces spp. has previously been tested, producing positive effects such as increased root length [54], which is consistent with the findings of the present work. It appears that the SMs derived from T. ruber may induce a shift in resource allocation [55], promoting root development without altering shoot phenology, which is regulated by thermal time accumulation [56]. This physiological adjustment may enable the production of seedlings at an optimal phenological stage for transplanting, while also enhancing root system traits that may benefit subsequent crop performance. This improvement could positively influence several key agronomic parameters in tomato cultivation, such as strengthening the physical anchorage of the plant to the soil, thereby reducing the risk of lodging or stem mechanical stress and improving overall plant stability [57]. Moreover, a larger root system increases the efficiency of water and nutrient uptake, potentially contributing to an improved tolerance to drought stress [58].
Regarding the physiological parameters evaluated, no significant differences were detected in chlorophyll, flavonol, or anthocyanin content. Similar results were also obtained by García-La Torre [32], who observed no significant changes in chlorophyll content despite an increase in root length following seed treatment with SMs extracted from Fusarium avenaceum, Sarocladium terricola, and Xylariaceae sp. A comparable pattern was observed in Phaseolus vulgaris [59] by foliar application of the SMs of Alternaria sorghi.
Our results, taken together, suggest that mycopriming with T. ruber extracts can positively influence vegetative development in tomato seedlings during the early stages prior to transplanting, particularly by enhancing root growth, which is associated with several agronomic advantages previously described. The reproducibility of this response was supported by the consistent results obtained in two independent trials. The hypothesis that seedlings with improved early vigor may exhibit a greater tolerance to subsequent biotic and abiotic stresses will be addressed in future research. Among the two formulations tested, the filtered extract appears to be the most viable option for practical implementation, as it involves a simpler extraction process and requires fewer inputs, thereby facilitating scalability and integration into industrial applications. Although it is highly probable that the growth-promoting effects of fungal extracts are due to the presence of secondary metabolites, further studies are needed to identify which specific metabolites are actually responsible for this biostimulant effect. Overall, this approach represents a sustainable strategy, both environmentally and economically, with a strong potential for integration into commercial nursery practices. Its simplicity of application and cost-effectiveness make it a promising tool for seedling producers, contributing to the production of more vigorous transplants aligned with the principles of sustainable agriculture.

5. Conclusions

Our study revealed the potential of the mycopriming technique using fungal extracts from endophytic fungi, specifically from the mycelium and filtrate of T. ruber, as a plant growth-promoting strategy in tomato cultivation. Although no significant improvements in the germination rate were observed, the treatments consistently showed a trend toward greater root system development in both independent trials. The reproducibility of this effect reinforces the robustness of the observed response. In contrast, no clear significant improvements were detected in shoot-related traits, including shoot length, aerial biomass, and leaf physiological parameters such as chlorophyll, flavonol, or anthocyanin content. This suggests the targeted stimulation of root development without substantial effects on the shoot during the early stages. These findings appear to support the hypothesis that seed treatments based on fungal extracts can effectively enhance early plant fitness. The application of these compounds directly to seeds may represent a viable alternative to the use of direct live microorganisms, which often face challenges related to field establishment, environmental variability, and regulatory constraints. This approach could offer a simple, scalable, and economically viable tool for commercial nurseries aiming to produce more vigorous tomato seedlings. Future studies should explore whether the improvements observed at the seedling stage translate into a better crop performance, greater resilience to biotic and abiotic stresses, and yield benefits after transplanting.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/agriculture15171868/s1, Table S1. Effect of seed treatments on the chlorophyll content, flavonol index, and anthocyanins index of tomato seedlings at 42 DAS. Values are means ± standard error. DAS = Days After Sowing. Table S2. Daily mean temperature, humidity, and radiation inside the greenhouse during the experiments. DAS = Days After Sowing.

Author Contributions

Conceptualization, Á.I.-G. and J.M.-G.; methodology, Á.I.-G., S.R. and J.M.-G.; formal analysis, Á.I.-G. and J.M.-G.; investigation, Á.I.-G. and J.M.-G.; writing—original draft preparation, Á.I.-G., J.P. and J.M.-G.; writing—review and editing, Á.I.-G., J.P., O.S., S.R., M.I.P. and J.M.-G.; funding acquisition, J.M.-G. and M.I.P. All authors have read and agreed to the published version of the manuscript.

Funding

This publication is part of the R&D project “PID2022-142403OA-I00 (BIOCROPPING)”, funded by MCIN/AEI/10.13039/501100011033/FEDER, UE and the Proof of Concept “TCUE10 067/2300003 Technical validation for the use of mycopriming as a sustainable strategy for the crop production and protection improvement” funded by the U. of Valladolid Foundation.

Data Availability Statement

The raw data supporting the conclusions of this article will be made available by the authors on request.

Acknowledgments

Thanks to María Felicidad López-Sainz and Evelio Alonso for all their help in the development of the work.

Conflicts of 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.

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Agriculture 15 01868 g001
Figure 1. Schematic workflow of the extraction of SMs from culture filtrate and mycelial biomass of T. ruber.
Figure 1. Schematic workflow of the extraction of SMs from culture filtrate and mycelial biomass of T. ruber.
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Figure 2. Schematic representation of the seed treatment process (mycopriming) using SMs extracts obtained from T. ruber.
Figure 2. Schematic representation of the seed treatment process (mycopriming) using SMs extracts obtained from T. ruber.
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Figure 3. Effect of seed treatments on the development of shoot length of tomato seedlings. Bars depict mean ± standard error. Different letters indicate significant differences according to Tukey’s HSD test (p < 0.05). (a) First trial; (b) second trial. DAS = Days After Sowing.
Figure 3. Effect of seed treatments on the development of shoot length of tomato seedlings. Bars depict mean ± standard error. Different letters indicate significant differences according to Tukey’s HSD test (p < 0.05). (a) First trial; (b) second trial. DAS = Days After Sowing.
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Figure 4. Effect of seed treatments on the shoot dry weight at 42 DAS. Values are means ± standard error. Different letters indicate significant differences according to Tukey’s HSD test (p < 0.05). (a) First trial; (b) second trial.
Figure 4. Effect of seed treatments on the shoot dry weight at 42 DAS. Values are means ± standard error. Different letters indicate significant differences according to Tukey’s HSD test (p < 0.05). (a) First trial; (b) second trial.
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Figure 5. Effect of seed treatments on the root length at 42 DAS. Values are means ± standard error. Different letters indicate significant differences according to Tukey’s HSD test (p < 0.05). (a) First trial; (b) second trial. DAS = Days After Sowing.
Figure 5. Effect of seed treatments on the root length at 42 DAS. Values are means ± standard error. Different letters indicate significant differences according to Tukey’s HSD test (p < 0.05). (a) First trial; (b) second trial. DAS = Days After Sowing.
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Figure 6. Effect of seed treatments on the root dry weight at 42 DAS. Values are means ± standard error. Different letters indicate significant differences according to Tukey’s HSD test (p < 0.05). (a) First trial; (b) second trial. DAS = Days After Sowing.
Figure 6. Effect of seed treatments on the root dry weight at 42 DAS. Values are means ± standard error. Different letters indicate significant differences according to Tukey’s HSD test (p < 0.05). (a) First trial; (b) second trial. DAS = Days After Sowing.
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Table 1. Statistical information from ANOVA tests corresponds to the influence of seed treatments on shoot length (14, 21,28, 35, and 42 DAS), and the root length, shoot dry weight, root dry weight, chlorophyll content, flavonol index, and anthocyanin index of tomato seedlings at 42 days. DAS = Days After Sowing.
Table 1. Statistical information from ANOVA tests corresponds to the influence of seed treatments on shoot length (14, 21,28, 35, and 42 DAS), and the root length, shoot dry weight, root dry weight, chlorophyll content, flavonol index, and anthocyanin index of tomato seedlings at 42 days. DAS = Days After Sowing.
First TrialSecond Trial
Analyzed ParametersDegrees of FreedomF-Valuep-ValueF-Valuep-Value
Shoot length 14 DAS20.780.4665.030.099
Shoot length 21 DAS20.670.5153.080.224
Shoot length 28 DAS21.160.3232.380.21
Shoot length 35 DAS23.790.033.340.165
Shoot length 42 DAS23.640.0341.230.753
Shoot dry weight23.500.041.050.355
Root length 212.73<0.00111.22<0.001
Root dry weight234.78<0.0013.480.037
Chlorophyll content (µg/cm2)20.020.9790.330.722
Flavonol Index20.760.4720.970.386
Anthocyanins Index 20.580.5640.080.923
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MDPI and ACS Style

Iglesias-Ganado, Á.; Poveda, J.; Santamaría, O.; Rodrigo, S.; Pozo, M.I.; Martín-García, J. Effects of Seed Priming with Talaromyces ruber Extracts on Tomato (Solanum lycopersicum) Growth. Agriculture 2025, 15, 1868. https://doi.org/10.3390/agriculture15171868

AMA Style

Iglesias-Ganado Á, Poveda J, Santamaría O, Rodrigo S, Pozo MI, Martín-García J. Effects of Seed Priming with Talaromyces ruber Extracts on Tomato (Solanum lycopersicum) Growth. Agriculture. 2025; 15(17):1868. https://doi.org/10.3390/agriculture15171868

Chicago/Turabian Style

Iglesias-Ganado, Álvaro, Jorge Poveda, Oscar Santamaría, Sara Rodrigo, María I. Pozo, and Jorge Martín-García. 2025. "Effects of Seed Priming with Talaromyces ruber Extracts on Tomato (Solanum lycopersicum) Growth" Agriculture 15, no. 17: 1868. https://doi.org/10.3390/agriculture15171868

APA Style

Iglesias-Ganado, Á., Poveda, J., Santamaría, O., Rodrigo, S., Pozo, M. I., & Martín-García, J. (2025). Effects of Seed Priming with Talaromyces ruber Extracts on Tomato (Solanum lycopersicum) Growth. Agriculture, 15(17), 1868. https://doi.org/10.3390/agriculture15171868

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