The Effect of Some Plant Extracts on Pathogenic Fungi Isolated from Greenhouses

Agricultural crops in greenhouses are the most intensive form of agricultural production, where ideal climatic conditions of temperature and humidity are available for plant growth, it is also vulnerable to the development of many fungal diseases that affect it and are transmitted through the leaves, stem and soil [1], as diseases are a major factor in the decline in agricultural yields, which leads to huge economic losses [2]. Since 1940, chemical and industrial fungicides have been used mainly to combat plant pathogens. Recent research has shown that the number of plant-pathogenic fungi is constantly increasing, as this increase leads to losses in agricultural products all over the world In addition to the negative effects caused by industrial pesticides on the environment, humans and animals, in addition to the resistance of fungi to these pesticides, all these reasons prompted scientists and researchers to search for new strategies to combat fungi [3]. The strategy is to implement a method that is safe, applicable and costs effectively to manage field diseases in the future, the use of plant extracts in agriculture is a suitable alternative method in the plant disease control program and they can act as major antifungals without leaving any toxic residues on the agricultural product [4].

Natural plant extracts regulate plant growth and participate in the defensive response, limiting the growth of pathogens. Various experimental conditions have led to the discovery of antifungal activity in aqueous extracts and organic solvents from plants of different origins [5]. Plant extracts are a source of active ingredients such as terpenoids, phenols, alkaloids, flavonoids, soaps, essential oils and others that are low in toxicity to crops, environmentally friendly and effective for fungal growth. According to previous studies, plant extracts have been used against a wide range of plant pathogenic fungi such as Alternaria solani, Aspergillus fumigatus, A. niger, A. flavus, A. fumigatus, Fusarium solani, F. oxysporum, Bipolaris orzyae, Botrytis cinerea, Curvularia lunata and F. verticilliodies [6]. The aim of the current study was to isolate the most important fungi causing disease from plant in some greenhouses in Diyala Governorate and to study the effect of treatment with water extracts of some plants towards these fungi.

Isolation and Diagnosis of Fungi

To identify disease-causing fungi in plants grown in some nurseries in Baqubah, the capital of Diyala Governorate, which included six plants: eggplant, pepper, cucumber, strawberry, chard and spinach, three samples were taken from each plant, bringing the total number of samples to 18. These samples included leaves showing some disease symptoms. The collection process took place during January and February 2025. The samples were placed in plastic bags labeled with all important information, including the plant type, the nature of the symptoms and the time of collection. The bags were then transferred to the Mycology Laboratory in the Department of Life Sciences, College of Education for Pure Sciences, University of Diyala, for fungal diagnosis.

After collecting the samples represented by plant leaves washing them with distilled water, sterilizing them with diluted alcohol and water and drying them on dry paper, the infected leaves were cut to a length of 1 cm under sterile conditions. The pieces of dry leaves were planted on a medium Potato Dextrose Agar medium (PDA), then the dishes were incubated at a temperature 25±2 for 3-7 days or until the fungal growths appear. After the fungal cultures grew, a sample was taken from each fungal culture and examined microscopically to determine the characteristics of the conides and to identify the fungal species.

The percentage of fungal isolates was calculated according to the following equation:

Percentage of appearance = N. of isolates of the genus or species/total N. of isolates × 100

Preparation of Plant Extracts

In order to test the effect of aqueous extract of some plants on fungi isolated from nursery plants, aqueous extracts of ginger, cloves and cinnamon were prepared, which were obtained from herbalists’ shops in the local market of Baquba city. Aqueous plant extracts were prepared by the method described by Ismail [7]. The plant samples were washed with distilled water, then the ginger samples were cut and left to dry for two weeks, while the cinnamon and cloves were washed, sterilized and left to dry. Each sample was then ground separately using a sterile grinder. Then weigh 100 grams of each ground plant material in 100 mL of distilled water (1:1 weight/volume) for 3 minutes and beat with a blender. The resulting extract was filtered using medical gauze in double layers to remove plant material residues. Then filter the extract again using filter paper. Place the centrifugally filtered extract at 4000 rpm for 5 minutes to obtain a homogeneous aqueous solution. The upper liquid of each solution was then filtered through a 0.45 μm diameter membrane filter to avoid any microbial contamination. Then the concentrations 25, 50 mL were prepared and stored in a dark glass container at a temperature of 5°C in the refrigerator until use.

PH Measurement

Weigh (1 g) of plant powder for each of the plants (cloves, ginger, students) and mix each type with (5 mL) of distilled water and leave for (10) minutes, then filter the solution and then measure the pH of the three solutions using a PH meter.

Evaluation of the Effectiveness of Extracts

To evaluate the effectiveness of plant extracts on the fungal isolates included in the study, calculate the percentage of inhibition for each extract and use the method of mixing the extract with the agricultural medium (PDA). The culture medium was prepared by sterilizing it in an Autoclave autoclave and leaving it to cool at 40°C. After that, concentrations of 25 and 50 mL of aqueous extracts were added to the PDA culture medium to obtain the required concentrations. After that, it was poured into plates and moved by hand to mix the extract with the medium and left to cool. The dishes were inoculated with the pathogenic fungi under study from a 7-day-old farm. Three replicates were used for each treatment and dishes were inoculated with the pathogenic fungus only without an extract for comparison. The dishes were incubated at a temperature of 26°C and after 10 days of growth the diameter of the fungal colony was measured for all treatments with the control treatment and the percentage of inhibition was calculated [8], using the following equation:

Inhibition (%) = (C –T) ̸ C×100

where, C is the average diameter of fungal colony in control treatment and T is the average diameter of the fungal colony grown in the extract.

Evaluation of the Effectiveness of Mixing Extracts

To test the mixing of two types of extracts under study on fungal growth, clove extract and cinnamon were mixed together and clove and ginger were mixed together in proportions of 25+25% and 50+50%, respectively, then the extracts were added to the PDA culture medium to obtain concentrations of 25, 50%. The dishes were inoculated with the pathogenic fungi under study from a 7-day-old farm, three replicates were used for each treatment, the dishes were incubated at a temperature of 26 m and after 10 days of growth the diameter of the fungal colony was measured for all treatments.

Statistical Analysis

The results were statistically analyzed using SPSS. The differences between the means were compared using Duncan's multiple range test at a probability level of 0.05 also the percentage increase between treatments compared to the control treatment was calculated.

Isolated Fungi

The results in Table 1 show the isolation of 42 fungal isolates belonging to 5 genera: Rhizopus spp. (5 isolates), Aspergillus spp. (7 isolates), Penicillium spp. (5 isolates), Fusarium spp. (11 isolates) and Alternaria spp. (14 isolates).

Alternaria spp. fungus recorded the highest incidence rate of 33.33%. It is worth noting that not all isolated fungi were pathogenic, with the exception of Fusarium spp. and Alternaria spp., which are both fungi that cause leaf blight. In Iraq, fungi are among the most common causes of rot and wilt diseases in nurseries. These fungi include Fusarium, Pythium, Rhizoctonia, Alternaria and Aspergillus. These fungi can cause significant economic losses in nurseries due to plant damage [9-11].

Table 1: Percentage of Appearance of Fungi Isolated from Plants Grown in Some Nurseries in Baqubah, the Capital of Diyala Governorate, Iraq

Table 2 shows a description of these fungi, as these results agreed with the study of Liu et al. [12] in the fungal specifications for fungal spinning and the conidial composition of the fungi under study.

Table 2: The Microscopic Diagnosis of Fungi Isolated from Plant Samples Grown in Some Nurseries in Baqubah City

pH of Plant Extracts

Table 3 shows the pH of the aqueous extract of ginger, cloves and cinnamon, which is an important indicator of the extract’s content of active compounds. Clove extract was found to be 5.22 more acidic compared to the acidity of cinnamon and ginger, which was 6.10, 6.31, respectively. Their acidity is close to moderate acidity, which is close to 7 and this indicates the presence of compounds of an acidic nature in these plants, such as phenols, terpenoids and volatile oils, which contribute to affecting fungal growth activity.

Table 3: Represents the pH Measurement of Plant Extracts

This is what Chaieb et al. [13] pointed out, where clove cabbage contains the compound Eugenol in high concentrations, which is a phenolic compound. Thompson [14] also pointed out in his study that medium and low pH can significantly affect fungal growth as for the cinnamon plant (cinnamon), it contains Cinnamaldehyde and some organic acids that give a relatively low pH value and have inhibitory activity for the fungi under study Alternaria and Fusarium and this is consistent with what Rao and Gan [15] mentioned. As for the ginger plant, it contains gingerol and shogol compounds, which have antioxidant effects and moderate acidity in aqueous solutions and this is consistent with Ali et al. [16]. Therefore, the different pH values of plant extracts indicate a variation in chemical composition and this variation affects the effectiveness of these extracts as antifungals or in their use as biological agents.

The Effect of Aqueous Plant Extract on Fungal Growth of Alternaria spp.

The results of the plant extracts (cinnamon, ginger and cloves) obtained from their effectiveness on the growth of the fungal colony of Alternaria spp. and in comparison, with the control treatment (control) without an extract are shown in Table 4.

Table 4: The Effect of Aqueous Extracts of Some Plants on Alternaria spp. Fungus Growth

Where fungal growth was affected by clove extract and this is clear on the diameters of the fungal colony in the two concentrations (25, 50%), with a complete effect, as the diameter of the fungal culture reached (0) mm with a 100% inhibition rate for each concentration and this is consistent with the study of Ahmad et al. [17] and with Rana et al. [18]. They mentioned widespread activity of cloves against all fungi and clove extract showed moderate to high antifungal efficiency and activity in control.

While cinnamon and ginger extract showed varying inhibition in the average diameters of fungal cultures for the two concentrations 25, 50%, ginger extract recorded the average diameter of the fungal colony (5.4) mm at a concentration of 25%, followed by cinnamon at the same concentration with an average diameter of the fungal colony (7.2) mm and an inhibition rate (36.47, 15.29%) respectively and this is consistent with the study Mohy et al. [19], While ginger extract at concentration (50) gave the highest inhibition with a diameter rate of the fungal colony (3.2) mm, followed by the researchers with a diameter rate of (5.5) mm with an inhibition rate of (62.35, 35.29%), respectively, where ginger and cinnamon extracts outperformed it in the inhibition rate in varying proportions. Comparing the results of colony treatments for Alternaria fungus treated with extracts with the results of the comparison treatment for a 7-day-old farm without extracts, where the diameter of the fungal colony was (8.5) mm, we find that the plant extracts significantly affected fungal growth and these results explain the effectiveness and inhibitory ability of plant extracts in reducing the spread of fungus and this is clear in Figure 1, as this study agreed with the study of Kisiriko et al. [20] with the study of Hyder et al. [21], they indicated that ginger extract has the ability to combat pests and fungal pathogens. The reason for this is the ability of active substances found in plants, such as phenolic compounds, terpenes and volatile oils, to inhibit because they have antifungal properties. This study is also consistent with Wijeweera et al. [22], who indicated that cinnamon has an inhibitory ability on the growth of a number of pathogenic fungi after being used as an alternative to synthetic fungicides because it contains essential oils such as Cinnamomum zeylanicum in the bark, which are concentrated, hydrophobic liquids as they contain volatile chemical compounds from plants and that these essential oils extracted from cinnamon have inhibitory effects on a large number of fungi, as agreed with the study Tabassum and Vidyas [23].

Figure 1 also shows the effect of the aqueous extract of the three plants on the diameter growth of Alternaria spp. fungus.

Figure 1: Effect of Plant Extract on Diameters of Colonies of Alternaria spp. Fungus

The Effect of Aqueous Plant Extract on Fungal Growth of Fusarium spp.

As for the results of Table 5, all extracts showed activity against Fusarium fungus, which led to a noticeable decrease in the growth of fungal colonies on Potato Dextrose Agar medium (PDA), where clove extract recorded the highest inhibition superiority, followed by cinnamon extract and then ginger extract in the two concentrations 25, 50% compared to the control treatment (control). Where clove extract gave inhibition at a colony diameter rate of 2.2 mm at a concentration of 25% and 1.0 mm at a concentration of 50% compared to the witness treatment where the colony diameter rate was 9.0 mm and the inhibition rate at the two concentrations was 75.55, 88.88%, respectively, while cinnamon and ginger extract at a concentration of 25%, the colony diameter rate reached (5.0, 8.5) mm and with an inhibition rate of (44.44, 5.55%), respectively. At a concentration of (50)%, cinnamon and ginger recorded a colony diameter rate of (2.3, 6.3) mm with a inhibition rate of (74.44, 30.00%), respectively, compared to the witness treatment The study proved the ability of these extracts to inhibit fungal growth to varying degrees, as this result was consistent with the results of the study of Jeewon et al. [24], where he stated in his study that clove extract exerts the greatest anti-fungal growth effectiveness by 100% At all concentrations, the reason is due to the presence of active substances such as glucuronides, glycosides and acidic compounds such as chlorogenic acid dissolved in the aqueous extract, unlike some studies that focused on essential oils extracted with organic solvents, when they considered that the inhibitory activity is due to the presence of the compound flavonoids and phenols [25,26].

Table 5: The Effect of Aqueous Extracts of some Plants on Fusarium spp. Fungus Growth

While the aqueous extract has proven its inhibition efficiency due to the presence of other compounds that dissolve in water, this was confirmed by the study of Hassan et al. [27], when they mentioned among the other existing compounds myricetin, quercetin, kaempferol and ellagic acid, which have an effect on fungal growth The study also showed the effects of the researchers as an antifungal due to the similarity of its chemical compounds to clove compounds, but at a lower level of inhibition. The difference in the structures of the substances responsible for inhibiting fungal growth may be the reason and this was confirmed by Olamilosoye et al. [28], in their study when they indicated that the difference in the proportions of the active substances may be responsible for the decrease in fungal growth activity These results were also consistent with the results of the study of Chrubasik et al. [29], where he confirmed that the aqueous ginger extract contains a chemical composition consisting of active ingredients such as carbohydrates, alkaloids, flavonoids, terpenes and phenols, which are compounds that contain antagonistic activity against pathogenic fungi Also, the study of Grzanna et al. [30], indicated the effectiveness of ginger against pathogenic fungi, as it indicated that ginger contains approximately 400 chemical compounds, including Gingerols, Zingerone, Shogaols and Sesquiterpenoids, in addition to volatile oils. This is consistent with the current study, as it confirms the effectiveness and ability of the extracts to reduce fungal growth, as shown in Figure 2.

Figure 2: Effect of Plant Extract on Diameters of Colonies of Fusarium spp. Fungus

Effect of Interaction between Plant Extracts on Growth of Alternaria and Fusarium Fungi

Table 6 shows the complete effect of mixing plant extracts on inhibiting the growth of the fungi under study when two types of them are mixed in different treatments. Regardless of the type and concentration of plant extracts used, all treatments showed high effectiveness in inhibiting the fungi Alternaria and Fusarium, as the inhibition rate was 100% at concentrations (25, 50) % with a colony diameter of (0.00) mm and for all treatments.

It is clear that mixing clove extract with students' extract and mixing clove extract with ginger extract, led to complete inhibition of the growth of the fungi under study. Also, raising the concentration from 25-50% did not show clear differences in effect, which indicates the effectiveness of the mixtures used even at lower concentrations. These results reflect the presence of a synergistic effect between plant extracts when mixed, which led to enhancing their biological effectiveness compared to using only one extract, as indicated by de Almeida et al. [31]. In previous studies, clove extract was reported to completely inhibit fungal growth even at the lowest concentration. Compared to the witness's treatment, the same researcher noted that the active antifungal components associated with cloves appear to be thermally stable, either by preparation in a water bath or by steam sterilization it is an important factor for its applicability in high temperature conditions. A study by Affonso et al. [32] showed that clove extract contains eugenol, β-caryophyllene and α-humulene, cinnamon extract contains trans-cinnamaldehyde, which is the predominant compound and ginger extract contains Gingerolo Shogsol as active ingredients with fungicidal activity. However, a large number of studies have shown antifungal activity against Alternaria and Fusarium fungi. It can be mainly attributed to the main active substances found in plants [33-35]. Despite the difference in the physiological and structural composition of the two fungi, the plant extracts mixed together showed equal inhibition efficiency, Figure 3, noting that the effectiveness of the low concentration of 25% was equal to the effectiveness of the concentration of 50% This indicates the possibility of using smaller quantities of different plant extracts mixed together, which is economically and environmentally important, as these extracts have a wide spectrum of fungal effects and can be used as safe natural alternatives instead of traditional chemical pesticides that may have harmful effects on health and the environment [6,17,24].

Table 6: Effect of Mixing Plant Extracts together on Fungal Growth of Alternaria and Fusarium

Figure 3: Effect of Mixing Plant Extracts together on Fungal Growth of Alternaria and Fusarium

The results indicate a synergistic effect when mixing two types of plant extracts and for all treatments with 100% inhibition of the growth of the fungi under study. This may not be achieved with the same efficiency when using one type of plant extract. However, the low concentration of 25% under study was sufficient to achieve complete inhibition, which allows the field to use lower concentrations of plant extracts in new studies, thus reducing the cost and negative damage to the environment and health when applied to agriculture. The results also proved that the extracts under study have an effective effect on the fungi under study despite the physiological difference between them, as these plant extracts can be used as alternatives to control fungal diseases in plastic homes and prevent the spread of the disease.

Recommendations

The same mixtures of plant extracts can be used on other types of pathogenic fungi to demonstrate the effectiveness of plant extracts. Study these transactions and apply them in the field to know their results more broadly on the plant. Safe plant extracts can be used instead of chemical pesticides because they are environmentally friendly and have lower costs.

1. Sanoubar, R., and L. Barbanti. “Fungal Diseases on Tomato Plant under Greenhouse Condition.” European Journal of Biological Research, vol. 7, no. 4, 2017, pp. 299–308.
2. Abass, M.H., and N.H. Mohammed. “Morphological, Molecular and Pathological Study on Nigrospora oryzae and Nigrospora sphaerica, the Leaf Spot Fungi of Date Palm.” Basra Journal for Date Palm Researches, vol. 13, nos. 1–2, 2014, pp. 26–38.
3. El-Baky, N.A., and A.A.A.F. Amara. “Recent Approaches towards Control of Fungal Diseases in Plants: An Updated Review.” Journal of Fungi, vol. 7, no. 11, 2021, p. 900.
4. Rahmatzai, N., et al. “In Vitro and In Vivo Antifungal Activity of Botanical Oils against Alternaria solani Causing Early Blight of Tomato.” International Journal of Biosciences, vol. 10, no. 1, 2017, pp. 91–99.
5. Askarne, L., et al. “In Vitro and In Vivo Antifungal Activity of Several Moroccan Plants against Penicillium italicum, the Causal Agent of Citrus Blue Mold.” Crop Protection, vol. 40, 2012, pp. 53–58.
6. Salem, M.Z., et al. “Plants-Derived Bioactives for Biosynthesis of Metallic Nanoparticles.” Microbial Pathogenesis, vol. 158, 2021, p. 105107.
7. Ismaiel, A. “Inhibitory Effect of Garlic Extract on Penicillic Acid Production and Growth of Penicillium hirsutum.” In Vitro Selection of Soybean Callus Resistant to Fusarium oxysporum Metabolites, 2008, p. 237.
8. Masangwa, J.I.G., et al. “Screening of Plant Extracts for Antifungal Activities against Colletotrichum Species of Common Bean (Phaseolus vulgaris L.) and Cowpea (Vigna unguiculata (L.) Walp).” Journal of Agricultural Science, vol. 151, no. 4, 2013, pp. 482–491.
9. Shaker, G.A. “Isolation and Identification of Fungi Infecting Aloe vera Plant.” Bulletin of the Iraq Natural History Museum, vol. 14, no. 1, 2016, pp. 91–97.
10. Tarad, K.W., and H.M. Saleh. “A Survey, Pathogenicity Assay, and Molecular Identification of the Pathogenic Fungi Associated with Pistachio in Anbar Province, Iraq.” Basrah Journal of Agricultural Sciences, vol. 36, no. 2, 2023, pp. 320–333.
11. Toofan, A.J. “Isolation, Purification, and Diagnosis of Fungi Isolated from Agricultural Nursery Soils in Waist Province and Determination of Their Pathogenic Ability.” Dijlah Journal of Agricultural Sciences, vol. 3, no. 3, 2024, pp. 98–105.
12. Liu, Q., et al. “Rhizopus stolonifer and Related Control Strategies in Postharvest Fruit: A Review.” Heliyon, vol. 10, no. 8, 2024.
13. Chaieb, K., et al. “The Chemical Composition and Biological Activity of Clove Essential Oil (Eugenia caryophyllata): A Short Review.” Phytotherapy Research, vol. 21, no. 6, 2007, pp. 501–506.
14. Thompson, D.P. “Influence of pH on the Fungitoxic Activity of Naturally Occurring Compounds.” Journal of Food Protection, vol. 53, no. 5, 1990, pp. 428–429.
15. Rao, P.V., and S.H. Gan. “Cinnamon: A Multifaceted Medicinal Plant.” Evidence-Based Complementary and Alternative Medicine, vol. 2014, 2014, p. 642942.
16. Ali, B.H., et al. “Some Phytochemical, Pharmacological and Toxicological Properties of Ginger (Zingiber officinale Roscoe): A Review of Recent Research.” Food and Chemical Toxicology, vol. 46, no. 2, 2008, pp. 409–420.
17. Ahmad, N., et al. “Antimicrobial Activity of Clove Oil.” Journal of Drug Targeting, vol. 13, no. 10, 2005, pp. 555–561.
18. Rana, I.S., et al. “Evaluation of Antifungal Activity in Essential Oil of Syzygium aromaticum (L.).” Brazilian Journal of Microbiology, vol. 42, 2011, pp. 1269–1277.
19. Mohy, S., et al. “Antifungal Activity of Cinnamon and Mint Extracts against White and Basal Rot of Garlic.” SVU-International Journal of Agricultural Sciences, vol. 4, no. 4, 2022, pp. 136–144.
20. Kisiriko, M., et al. “Phenolics from Medicinal and Aromatic Plants: Characterisation and Potential as Biostimulants and Bioprotectants.” Molecules, vol. 26, no. 21, 2021, p. 6343.
21. Hyder, S., et al. “Use of Botanical Extracts and Bacterial Inoculants for the Suppression of Alternaria solani Causing Early Blight Disease in Tomato.” 2023.
22. Wijeweera, A.A., et al. “Antifungal Activity of True Cinnamon (Cinnamomum zeylanicum) Essential Oil against Postharvest Pathogens.” Proceedings of the Open University Research Sessions, 2021.
23. Tabassum, N., and G.M. Vidyasagar. “Antifungal Investigations on Plant Essential Oils: A Review.” International Journal of Pharmacy and Pharmaceutical Sciences, vol. 5, no. 2, 2013, pp. 19–28.
24. Jeewon, R., et al. “Antioxidant and Antifungal Properties of Cinnamon and Clove Extracts.” Pathogens, vol. 13, no. 6, 2024, p. 436
25. Mostafa, A.A.F., et al. “Phytochemical Analysis, Antiproliferative and Antifungal Activities of Syzygium aromaticum Solvent Extracts.” Journal of King Saud University–Science, vol. 35, no. 1, 2023, p. 102362.
26. Abdul Aziz, A.H., et al. “Unlocking the Full Potential of Clove (Syzygium aromaticum): An Overview.” Processes, vol. 11, no. 8, 2023, p. 2453.
27. Hassan, S.M., et al. “Productivity and Post-Harvest Fungal Resistance of Hot Pepper.” Plants, vol. 10, 2021, p. 662.
28. Olamilosoye, K.P., et al. “The Aqueous Extract of Ocimum gratissimum Leaves Ameliorates Acetic Acid-Induced Colitis.” Egyptian Journal of Basic and Applied Sciences, vol. 5, no. 3, 2018, pp. 220–227.
29. Chrubasik, S., et al. “Zingiberis rhizoma: A Comprehensive Review.” Phytomedicine, vol. 12, no. 9, 2005, pp. 684–701.
30. Grzanna, R., et al. “Ginger—An Herbal Medicinal Product with Broad Anti-Inflammatory Actions.” Journal of Medicinal Food, vol. 8, no. 2, 2005, pp. 125–132.
31. de Almeida, E.N., et al. “Potenciais Alternativas com Extratos Vegetais no Controle da Pinta Preta do Tomateiro.” Revista Verde, vol. 12, no. 4, 2017, pp. 687–694.
32. Affonso, R.S., et al. “Aspectos Químicos e Biológicos do Óleo Essencial de Cravo-da-Índia.” Revista Virtual de Química, vol. 4, no. 2, 2012, pp. 146–161.
33. Jing, C., et al. “Essential Oil of Syringa oblata as a Potential Biocontrol Agent.” Crop Protection, vol. 104, 2018, pp. 41–46.
34. Sharma, A., et al. “Antifungal Activities of Selected Essential Oils.” Journal of Bioscience and Bioengineering, vol. 123, no. 3, 2017, pp. 308–313.
35. Šernaitė, L., et al. “Extracts of Cinnamon and Clove as Potential Biofungicides.” Plants, vol. 9, no. 5, 2020, p. 613.