Native Trichoderma Strains Biocontrol Potential against Soil-Borne Pathogens: Strawberry

Abstract

Strawberry production remains important in the world. Soil-borne fungal pathogens (such as Macrophomina phaseolina, Rhizoctonia spp., Fusarium oxysporum, Phytophthora spp., and Pythium spp.) are causing serious problems for strawberry farmers. Distinct treatments, such as fumigation, resilient varieties, solarization, rotating crops, synthetic fungicides, and cultural practices are used to combat infections of soil-borne in strawberries. Since strawberry fruits are consumed immediately, fungicide treatments raise a number of problems, including pesticide residue on the fruits which gives harmful effects on consumers. Solarized soils are often effective against certain soil-borne pathogens. New studies have focused on eco-friendly biological control agents (BCAs) that can be used as effective substitutes for fungicides. Trichoderma strains are efficient BCAs that have different mechanisms against soil-borne diseases in strawberries. Despite the success of commercial Trichoderma-based products, their low efficacy or ineffectiveness against targeted pathogens are major limitations under field conditions. Native Trichoderma strains that can be used to control this disease are ideal antagonists. This section discusses the potential of native Trichoderma strains to combat soil-borne pathogens in strawberry fields.

1. Introduction

Strawberry (Fragaria × ananassa Duchesne ex Rozier) have been around since ancient and is a member of Rosaceae family [1]. China is one of the top manufacturers of strawberries, in addition to the US, Türkiye, Mexico, Egypt, and Spain are significant producers. In 2023, there were 7.9 billion people on the planet, and by 2050, it’s predicted that there would be about ten billion [2]. The need for more readily accessible food supplies is driven by the increase in population intensity. Abiotic factors can significantly harm agricultural crop systems. For example, worldwide warming and climate change are significant factors in these factors [3]. Fungi, bacteria, viruses, and other parasites are caused an important infection in crop production [4]. Although soil-borne plant diseases are extensively dispersed, only a few species exhibit a pattern of limited distribution. At the same time, crops may be at risk if pests, which serve as vectors for spreading plant infections, change their distribution patterns [5]. The prevalent strawberry pathogens enclosing Macrophomina phaseolina, Rhizoctonia solani, Fusarium spp., Phytophthora fragariae, P. cactorum, Pythium spp., Verticillium dahliae, Botrytis cinerea, Colletotrichum acutatum, Colletotrichum gloeosporioides, Sphaerotheca macularis, Phomopsis obscurans, Gnomonia comari, and Xanthomonas fragariae [6, 7, 8, 9, 10, 11]. These pathogens are frequently difficult to control. They are free-living organisms with a diverse variety of hosts and the ability to thrive for extended periods on soil organic materials and plant detritus. However, these pathogens of fungi have resistant structures that can be produced even in the absence of plants, such as sclerotia, microsclerotia, oospores, or chlamydospores. Additionally, owing to the likeness of symptoms, diagnosis is challenging and time-consuming [12]. Strawberry growers use synthetic fumigants and chemical fungicides in an orderly round the production season to reduce soil-borne diseases. The extensive use of fumigants and fungicides has a negative impact on soil and warm-blooded [13]. Cultural precautions, such as crop rotation, bio-fumigation, anaerobic soil disinfestation, and soil solarization, are embraced by farmers; however, these methods have inconsistent results and are ineffective in soil-borne disease management. In addition, the increase in crop diversity in agriculture has necessitated the creation of new research strategies [14]. Biological control can be an alternative for the management of plant diseases. The Trichoderma genus (Hypocreales, Ascomycota) is extensively used to control soil-borne diseases and to promote growth in different plants [10, 15, 16]. They have several antagonistic tools such as mycoparasitism [17], antibiosis [18], production of cell wall-degrading enzymes [19], rhizosphere and root colonization [20], and nutrient competition [17]. Trichoderma is widely used in bio-remediation in pollutants of soils and waters [17], as regional and systemic resistance-inducing in plants [21]. Trichoderma species or isolates can show different levels of effectiveness in different geographic locations, diverse crops, or cultivar functions [22, 23, 24]. Therefore, it is important to use native Trichoderma isolates for protection from soil-borne diseases in the field. This review informs the use of native Trichoderma, with some perspectives on the biocontrol potential of strawberry production.

2. Strawberry production and soil-borne diseases

2.1 Cultural practices of strawberry production

Strawberries are cultivated commercially in a variety of settings, including open fields, polytunnels, and glasshouses [25]. High tunnel production is employed to extend the strawberry growing season and yield earlier than open-field production. Greenhouses have been enabled for a year in strawberry production [26]. The interval on strawberry plants is usually 30 cm by 30 cm and 1.5 m between each bed in the field [27]. Many different factors are considered when selecting a variety of strawberries. These include locations, production methods, and customer choices. Strawberry plants can be divided into three primary groupings based on their flowering behaviors. Plants of long-day begin flowering under long-day conditions and generate twice harvests each season. June-bearing strawberries, commonly referred to as short-day strawberries, give a start of flowering under short-day conditions. These plants are provided only one harvest per season. Day-neutral cultivars depend on temperature differences for flower commence and day-long is not important. Strawberry production in the field is preferred of day-neutral cultivars [28]. According to the growth stage, strawberry plants require between −0.016 and 0.032 L of water per week [29]. When growing strawberries, it is crucial to know when and how much irrigation is used so that the fruit receives the necessary moisture while preserving labor and water resources [30, 31, 32].

2.2 Soil-borne diseases in strawberry

Serious soil-borne diseases influencing strawberry production are Phytophthora root rot (Phytophthora spp.), black root rot (Pythium spp., Rhizoctonia solani), Fusarium wilt (Fusarium oxysporum), charcoal rot (Macrophomina phaseolina), and Verticillium wilt (Verticillium dahliae). These pathogens have spread all over the world [7, 33, 34, 35]. Without disease management, these soil-borne diseases led to 20–30% output reductions in strawberry yield [36, 37]. The use of an overhead irrigation method causes early-season outbreaks of Oomycete-induced diseases in annual strawberry production [38, 39]. Different species of Phytophthora (Stramenopila, Peronosporaceae) cause crown rot in strawberries. These species as P. cactorum, P. fragariaefolia, P. citricola, P. nicotianae, and P. citrophthora [40, 41, 42]. In the studies carried out, Phytophthora was initially determined only from soil or crown could. But as a result of the studies carried out in subsequent processes, it was determined that isolates obtained from other host plants and strawberry fruit also caused leather rot [43, 44]. Phytophthora cactorum was first recorded as ground leather rot on fruits and crown rot in strawberries [44]. Owing to the continual presence of strawberry plants in the cultivation of perennials and plantations, the source of inoculum might include oospores [45]. The first symptoms appear at the onset of bluish-green color on new leaves, after which the plant begins to wilt. Plants wilt and die within days due to disease progression and crown rot [46]. Phytophthora fragariae causes red core, which can be leading to plant death in strawberry-cultivated regions [47]. The definition of the disease indicates dark reddish-brown staining of crowns that begins at the upper or lower and the breakdown of vascular texture. Since secondary infections show rare throughout the one crop cycle, the disease develops in a monocyclic pattern. The parent inoculum source was an infected plantation. Additionally, soil fumigation prior to planting is sometimes unsuccessful in eradicating this disease in fruit-producing areas [39, 48]. Most strawberry varieties are not tolerant to Phytophthora. Black root rot is a common disease that causes the death of feeder roots and degrades the structural roots in strawberries. It limits productivity and affects strawberry production worldwide [49, 50]. The genera Rhizoctonia and Pythium largely cause the black root rot complexes [51, 52]. Rhizoctonia spp. are associated with the black root rot complex and fall into an imperfect Basidiomycete fungus [53]. Rhizoctonia isolates are classified as multinucleate or mononucleate [54]. R. solani is the high virulent than R. fragariae in strawberry plants [55, 56]. Soil fumigation is still the only effective treatment for root rot by Rhizoctonia in strawberry [57]. The early symptoms exhibit only a few plants, which are mostly found in poorly drained and compacted soil. Plants that have been affected lack feeder roots, and many of the bigger roots have broken off at rotten locations where the cortical tissue has collapsed. Because of root rot, some plants lose their lives throughout the growing season, whereas those that survive will be stunted and will yield fewer strawberries [58]. The genus Pythium (Pythiaceae, Oomycota) has 327 described species [59]. Some species were only recently identified from Phytopythium in strawberries [38, 60]. Fusarium wilt is an important disease of strawberries worldwide. This disease was reported Fusarium oxysporum f. sp. fragariae in several countries [34, 61, 62, 63]. The first symptom of Fusarium is common to flower or fruit set in well-grown of strawberries. Here, the oldest leaves starting wilt, become gray-green, and then dry out [64]. Macrophomina phaseolina (Botryosphaeriaceae), a soil-borne phyopathogen fungus, is found worldwide and affects over 500 plant species in 100 families. Diseases including charcoal rot, rot in the stem as well as root, and seedling blight are brought on by this pathogen in strawberry [65]. The main infectious source of M. phaseolina is microsclerotia. This resistant construction can last in the soil for 15 years [66]. The intensity of disease increases when temperatures of aerial and soil reach 30–35°C and lowly 60% of soil humidity [67]. The germinating hyphae of M. phaseolina are able to infect roots during the seedling phase. Afterward, the fungus influences the vascular system and distorts the transfer of water and nutrition in the plant. Yield loss is related amount of inoculum in the soil at the same time intensity with the severity of the disease [67]. Verticillium genus in the phylum Ascomycota accounts for the vascular wilt of many plants. The species V. dahliae and V. albo-atrum cause serious economic losses worldwide [68]. Verticillium dahliae is common in strawberry-growing areas, and it can be particularly severe when springtime temperature fluctuations might stress the plants [69]. The conidia, or microsclerotia, of the pathogen, germinate in the being of root secretions; upon this, the germ tubes penetrate the plant roots. The pathogen can survive for more than ten years in the soil or as microsclerotia (ms) on tissues of dead plants [70, 71, 72]. Microsclerotia concentration is 2 ms/g soil that can rise 100% wilt in strawberries [73]. Therefore, this pathogen is rough to struggle with present management strategies. Some fungicides are utilized based on the targeted pathogens, including azoxystrobin, carbendazim, prochloraz, metalaxyl, mancozeb, difenoconazole, pyraclostrobine, dimethomorph, chlorothalonil, tebuconazole, and fludioxonil [74]. Azoxystrobin, metalaxyl, and difenoconazole due to the often use of fungicides, these pathogens have developed resistance to these fungicides. As a result, chemical combat is unsuccessful in offering enough control for the disease [75, 76]. There is no one-size-matches-all-solution to disease control in soil-based strawberry growing, and a combination of strategies can be useful. The soil fumigant Methyl Bromide (MB) controls a broad wide of pathogens, pests, and weeds, so farmers have preferred it often. MB was phased out in 2005 below the Montreal Protocol because of its impacts as the chief ozone stratum thinner, notwithstanding its effectiveness [77]. Holmes et al. [78]. summarized MB options with the inclusion of recent fungicides, stubborn varieties, solarization, anaerobic soil disinfection, plastic films, and cover crops. Soil fumigants used to substitute MB comprise 1–3-dichloropropene (1,3-D), Chloropicrin (Pic), Dazomet (DZ), and Metam Sodium (MS), Metam Potassium (MP) [26]. Solarization is used as an alternative treatment for pathogens in tropical regions. Solarization involves wetting the soil and then covering it with a transparent film to raise the soil temperature during the summer. The transparent film remains closed for 4–6 weeks. Yet solarization is not practicable in loud-altitude regions where strawberry production occurs [79].

3. Biocontrol mechanisms of Trichoderma

Trichoderma species have different mechanisms, which are briefly explained as follows. The mycoparasitism mechanism of Trichoderma takes place with many sequential actions: (i) positive chemotrophic growth toward the host, (ii) direct contact with the phytopathogenic fungus, and (iii) coiling around the host hyphae. Trichoderma also undergoes morphological changes in hyphae, which enables it to penetrate the host hyphae and death its biomass. These changes include the formation of appressorium-like penetration structures and the production of cell walls that degrade hydrolytic enzymes (CWDEs) [19]. CWDEs include chitinase, glucanase, N-acetylglucosaminidase, and protease [80]. The second biocontrol mechanism of Trichoderma is antibiosis. Trichoderma species generate a wide range of small-molecule compounds as secondary metabolites (SMs), including pyrones, terpenoids, steroids, and polyketides. Additionally, Trichoderma produces siderophores and a significant amount of peptaibiotics known as peptaiboles, which frequently include non-standard amino acids [18]. The 6-pentyl-alpha-pyrone (6-PP) is one of the most studied in Pyrones group. This compound has been associated with yellow pigmentation and a coconut aroma for production in some strains of Trichoderma. Moreover, this compound exhibited antimicrobial activity. Polyketides (PKs) have antimicrobial activity. The role of PKs has to simplify competition for nutrients, reduce the ability of pathogens, and set chemical communication with organisms [81]. Another biocontrol mechanism is competition. Trichoderma species’ ability to displace other fungal species in the rhizosphere is that they are excellent contestants for ground and nutrients. Trichoderma strains that efficiently absorb nutrients and develop more quickly than their rivals will have a clear advantage in their ability to colonize and thrive in various habitats [82]. Another mechanism involves an increase in plant growth. Trichoderma species realize root colonization, plant nutrition, and growth, as well as enhance plant resistance to abiotic stresses [83]. Trichoderma has been observed to induce systemic resistance for both monocots and dicots plants. This reaction includes plant recognition of the fungus through systemic induced resistance (ISR), which is mediated by the phytohormones ethylene (ET) and jasmonic acid (JA) [17]. Trichoderma also stimulates the expression of genes related to pathogenesis (PR), which is mediated by salicylic acid (SA). This reaction, also brought on by biotrophic and hemibiotrophic infections, is referred to as systemic acquired resistance (SAR) [84]. The pollution of water and soil is occurring taking by extreme pesticides and synthetic fertilizer utilization in plant production fields. Chemical substances can be removed using either methods of biological or chemical [85]. In recent research, Trichoderma species have executed their skills to remediation on different fungicides, insecticides, and herbicides [86, 87]. This biological control agent successfully detoxifies into sulfonylurea (herbicide) [86], dichlorvos (insecticide) [88], carbendazim [89], and penthiopyrad [90].

4. The use of the antagonistic properties of native Trichoderma species against soil-borne pathogens in strawberry

In Giza, Egypt, a study using four distinct Trichoderma species to treat strawberry black root rot was carried out. The pathogen isolates F. solani, R. solani, and Pythium sp. employed in the investigation was isolated from strawberry growing areas. Black root rot was assessed in vitro and in field settings using native T. harzianum, T. viride, T. virinis, and T. koningii isolates. The in vitro investigation revealed that the pathogen isolates had their mycelial development inhibited by T. harzianum 92.1, 91.7, 93.4%, T. viride 91.7, 92.9, 90.3%, T. virinis 87.4, 86.6, 84.3%, T. koningii 92.1, 93.4, 90.6%, respectively. A variety of Festival strawberries was evaluated for plant growth, yield, and disease severity in field conditions. The combination of all Trichoderma isolates produced the greatest rise in the fresh and dry weight by 83.3 and 176.9%, respectively. Moreover, the mix of Trichoderma species showed the highest increase in yield (117.1%). Single-proceedings of T. harzianum, T. viride, and T. koningii raised the fresh weight of plants by 105 to 68%, and these isolates showed increasing yield by 71.1, 57.1, and 64.3% respectively. T. virinis was less efficient in fresh-dry weight and yield. The Trichoderma mix treatment enhanced the peroxidase and chitinase activity in strawberry leaves by 150 and 160.9%, respectively [91]. Rhizoctonia solani, Fusarium solani, F. oxysporum, and Macrophomina phaseolina of diseased strawberry plants were collected from Qalyubia Governorate, Egypt. Trichoderma album, T. harzianum, T. viride, and T. hamatum were isolated from rhizospheric soils in the roots of healthy strawberry plants. In vitro test results, all pathogens were reduced growth by T. harzianum 83.43, 78.53, 67.10, 69.50%, T. album (77.53, 72.67, 66.53, 68.43%), T. hamatum (55.70, 63.27, 56.53, 53.33%), T. viride (74.57, 70.03, 65.47, 61.23, 67.83%), respectively. Field treatment results of disease incidence (7-weeks post transplanting), T. harzianum showed the highest impact (77.0, 67.2%) follow up by T. album (72.0, 63.4%), T. hamatum (27.0, 29.9%) in the 2015/16 and 2016/17 seasons, respectively. T. harzianum was the most successful treatment in terms of chlorophyll, protein, total nitrogen, total phenols, and total sugars. Moreover, this treatment greatest increased in yield (36.84% and 25.22%) when compared to the control treatment over the two consecutive growing seasons [92]. Trichoderma harzianum strain T-H4 inhibited mycelial growth on Rhizoctonia sp. 70.22 ± 5.46, and Fusarium sp. 63.65 ± 1.50 in dual culture test [93]. Mirmajlessi et al. [94] isolated V. dahliae (29 isolates) from strawberry-growing areas in Estonia. V. dahliae isolate SV-19 had high virulence (79.51%). Volatile metabolites of T. harzianum isolates showed different inhibitory values on V. dahliae, from 15.8% to 88.3%, while TU79 determined the maximum effect on the pathogens. This isolate had significant mycelial inhibition in dual culture (92.1%) and non-volatile metabolites. The results of in vitro studies chosen seven isolates (TU63, TU68, TU72, TU74, TU75, TU79, and TU80) (mycelial inhibition rate > 50%) for the greenhouse treatment. In greenhouse studies, the antagonist isolates were observed with different rates of disease severity from 14.2% to 75.6%. The isolate of TU79 represented only the highest reduced disease severity (≈27%) that was applied to the soil or root [94]. The efficiency of four T. harzianum was analyzed against F. oxysporum f. sp. fragariae using a dual culture approach. Solely one strain of T. harzianum observed to inhibit pathogen growth. This isolate treatment protected strawberry plants (80.0%) in the greenhouse after 42 days [95]. The present study identified harzianic acid produced by T. harzianum M10, and hydrophobin produced by T. longibrachiatum MK1 effect on strawberry plant (cv. Sabrina) growth in Naples, Italy. The plant-growing season started in October 2016 and ended in June 2017, and the fruits were harvested once each week from April to June 2017. The harzianic acid increased by 24% in total fruit yield (g plant⁻¹) and it had the maximum number of fruits for each plant (14%). Also, this treatment showed the highest increase in the total soluble solids content (8%). The hydrophobin had effectiveness on the ascorbic acid content (9%), and it showed an increment in root length (15%), root fresh weight (15%), and dry weight (19%). The maximum content of cya 3-O-glc and pel 3-O-rut was provided by hydrophobin as 63%, 11%, respectively [96]. Native T. citrinoviride determined the ability to biocontrol of R. solani (isolated from strawberry root) in dual culture and pot trial by Sekmen Cetinel et al. [97]. The result of the dual culture test, T. citrinoviride showed a high inhibition of 79% against R. solani. T. atroviride + R. solani using determined disease incidence from 33% to 41%, and Trichoderma pre-treatment increased the dry weight of strawberry plant (cv. Rubigen) in pot trial. Moreover, this treatment indicated a higher plane of PSII. Trichoderma isolates, R. fragariae,and R. solani were isolated from different strawberry fields regions in Menoufia, Egypt. T. harzianum and T. hamatum in vitro test showed different inhibition values on R. fragaria by 83.3%, 72.2%, respectively. This biocontrol agent effect in field trials determined on disease severity of R. fragaria of strawberry plants (cv. Sana) by 9.6%, 6.8%, respectively. The group control had a disease severity of 86.4%. T. harzianum and T. hamatum increased yield (g/plant) by 50.4%, 33.2%, respectively [98]. R. solani and native Trichoderma isolates isolated from strawberry roots and soils in Qingdao, China. These Trichoderma isolates are namely T. atroviride T1, T. harzianum T2, T. atroviride T3, T. harzianum T4, T. harzianum T5, respectively. In the dual, non-VOC, and VOC assays, T1 and T3 had maximum inhibition rates of 60.4–100–75.3%, 60.9–100–69.8%, respectively. All native Trichoderma isolates showed well-enzymatic activities of protease, cellulose, chitinase, and glucanase. Another result obtained from this study is that the antagonistic effect of the five Trichoderma isolates against R. solani in the petioles of strawberries was ordered as follows: T2 (34.8%) > T4 (−16.7%) > T3 (−46%) > T5 (−171.5%) > T1 (−172%) [99]. Native T. viride isolates were collected from the rhizosphere of sound strawberries. The pathogen isolate was R. fragariae which was isolated in the northwest of Egypt in Ismailia district. The antagonist inhibited the mycelial growth of Rhizoctonia by 69.5%. The ethylene synthesis increased when the assessment 2–7 days after the process in plant assays of R. fragariae + T. viride treatment. The maximum SOD activity was considered at day 6 (T3, T4, and T5), increased at day 7, and stayed high at day 8 on the treatment of T3, T4, and T5 in field and greenhouse studies. The T3 treatment showed superlative CAT activity on day 4, while T4 and T5 remained stable until the end of the field and greenhouse trials. The Trichoderma treatments of plant fruit numbers showed a difference: T3, T4, and T5 had maximum fruit but T2 had minimum fruit in the greenhouse and field. In strawberry plants treated with Trichoderma, there was a lower disease incidence and a bulkier root than in the other plants [100]. Different isolates of T. viride, T. viride, T. hamatum, T. koningii, and T. harzianum species were obtained from soil samples taken from strawberry production areas in Buhayre province in Egypt. These isolates were evaluated against M. phaseolina (M1 and M3 isolates) isolated from strawberries showing symptoms of charcoal rot disease from the same region under in vitro and greenhouse conditions. As a result of the dual culture test, T. viride isolates had the highest inhibition rate against M. phaseolina isolates. As a result of the study conducted under greenhouse conditions, it was reported that T. hamatum (1, 2) application had the best effect on the survival rate of pathogen-infected plants [101]. Korkom and Yildiz [102] investigated ten Trichoderma isolates isolated from the soil of strawberry production areas in Aydin province, Türkiye, and their obtained effects on M. phaseolina under in vitro and in vivo conditions. Within the scope of antagonistic studies carried out in vitro, it was determined that Trichoderma isolates limited the mycelial growth of M. phaseolina by 25.9–59.1% in dual culture and VOCs formed by Trichoderma isolates by 13.3–30.0%. In addition, it was determined that Trichoderma isolates reduced microsclerot formation in the dual culture assay by 11.7–63.1% and the effect of volatile compounds by 9.7–77.3%. In vivo, the study was carried out by simultaneous application of antagonists and pathogen to strawberry plants (cv. Rubygem) (Tr + Mp) and pathogen inoculation 15 days after antagonists application (Tr + Mp15). Tr28 showed the highest weight rate (36.47%) and no plant death was observed in Tr + Mp. In Tr + Mp(15), Tr25 was observed the highest wet weight rate (47.37%) and plant death did not occur in Tr26, Tr24, Tr21, Tr28. T. harzianum (sixteen isolates), T. virens (three isolates) were obtained from the soil in strawberry production areas of Aydin province, Türkiye. The effects of these isolates on M. phaseolina and plant growth in strawberries (cv. Festival) under in vitro and in vivo conditions. Tvr4 (T. virens) inhibited the highest rate (66.4%) of mycelial growth of the pathogen in the dual culture test. The VOCs produced by Tvr2 limited the mycelial growth of the pathogen (33.3%). Thr15 (T. harzianum) and Tvr4 reduced the highest rate of microsclerot formation by 80.5%, 73%, respectively. Thr15 provided the highest plant wet weight rate (281.95%) when the antagonists and pathogen were applied to the soil at the same time in vivo assay. Furthermore, no mortality occurred in plants treated with Thr13 and Thr14 isolates. Thr20 was determined to be the isolate with the highest plant wet weight rate (411.47%) in the pathogen when it was applied to the soil 15 days after the antagonist’s application. No mortality occurred in the plants applied at Thr13 and Thr14. Thr22 and Thr6 provided high wet weight rates of 344.93%, 331.15%, respectively, in the plant growth assay [103]. The isolation and identification of Trichoderma spp. from different agricultural areas of Aydin province, Türkiye. Eighty-eight Tichoderma isolates were obtained from 165 soil samples in Aydin province. T. afroharzianum, T. guizhouense, and T. harzianum by morphological and molecular identification in this study of Trichoderma isolates. The T. guizhouense isolates obtained in this study are the first records for Türkiye. These antagonistic isolates were carried out to determine their biological control potential against charcoal rot disease and plant growth in strawberries in vitro, in vivo, and in field conditions. In vivo and field studies were carried out on the Fortuna strawberry variety, and the trials were repeated for two years. As a result of the study conducted under greenhouse and field conditions, the TrMix application had the best effect on plant mortality (mean 14.1%) and yield (mean 29.7%). In field studies, native T. afroharzianum isolates were applied five times during strawberry production per season and were successfully colonized in the soil. Moreover, all Trichoderma isolates showed the highest enzymatic activities, including chitinase, sellulase, and sidephore [35].

5. Conclusions

From the perspective of agriculture, the main issues surrounding soil and environmental health include an increase in pesticide residue in soil and water, a decrease in soil-beneficial microorganisms, changes to the physical and chemical makeup of the soil, and pesticide resistance of the pathogen. This chapter of the book compiled how novel Trichoderma species control soil-borne diseases in strawberries. Many studies have indicated that Trichoderma species have multiple beneficial effects on strawberries, that not only include disease control, but also the stimulation of plant growth, increased yield, uptake of nutrients, and healing of crop quality. Therefore, the interactions that take place between soil-borne pathogens, micro- or macroorganisms, and even the physicochemical environmental conditions, it is crucial to thoroughly comprehend these interactions as possible for disease management measures to apply them as effectively in strawberry production. Additionally, further research is needed to develop models for different systems to assess the application of native Trichoderma isolates in strawberries.