Trichoderma Strains Research Articles

Exploring Trichoderma Species in Industrial Wastewater: Morphological and Molecular Insights from Isolates.

The genus Trichoderma holds economic significance due to its widespread distribution and diverse applications, including biological control, enzyme production, and various biotechnological uses. The accurate identification of Trichoderma species is crucial given their close association with human activities. Despite previous efforts in classification, a comprehensive analysis combining morphological and molecular approaches is necessary. This study focuses on the isolation of four Trichoderma species from industrial wastewater in Pakistan, expanding on the known diversity in the region; isolation involved collecting samples from industrial wastewater effluents at specific sites in Punjab, Pakistan. Trichoderma strains were cultured and purified on solid media, with subsequent biomass production for bisorptional activity. Morphological characterization included colony features and microscopic examinations. DNA extraction, polymerase chain reaction (PCR), and sequencing of the internal transcribed spacer (ITS) region were conducted for molecular analysis. Phylogenetic analysis was performed using the Maximum Likelihood Algorithm. The study identified three Trichoderma species, viz. T. citrinoviride, T. erinaceum, and T. longibrachiatum. Each species was characterized morphologically and supported by molecular-phylogenetic analysis. Illustrations of microscopic features and a phylogenetic tree based on the ITS-nrDNA region were recorded. T. citrinoviride and T. longibrachiatum, isolated from steel mill and tanneries wastewater, respectively, were differentiated based on morphological characteristics such as phialides and conidia. The combination of morphological and molecular techniques enhances the accuracy of species identification. The study highlights the significance of Trichoderma in industrial wastewater environments and underscores the need for continued research in this area. Future research should focus on exploring the ecological roles and potential applications of the newly identified Trichoderma species. Additionally, further investigations into the biotechnological potential of these species, including enzyme production and bioremediation capabilities, would contribute to their practical applications.

Degradation ability of Trichoderma spp. in the presence of poly(butylene adipate-co-terephthalate) microparticles

Investigating the effects of microplastics remains a pertinent issue given the extensive biodiversity of exposed organisms, variations in the mechanisms of action among individual polymers, and their reliance on environmental conditions. Therefore, the objective of the study was to investigate some interactions of the popular biodegradable plastic poly(butylene adipate-co-terephthalate) (PBAT) on some aspects of the physiology of filamentous fungi Trichoderma spp., integral components of the soil microbiome known for promoting plant growth and aiding in pollution remediation. In the two Trichoderma strains examined, a positive influence on fungal growth was observed in the presence of microplastics (MPs). The capability to degrade MPs with the involvement of cytochrome P450 monooxygenases was confirmed through the detection of terephthalic acid (TPA) in postculture extractions. Additionally, inhibition of degradative activity in the presence of MPs was observed for metolachlor (MET) and 2,4-dichlorophenoxyacetic acid (2,4-D). Moreover, biodegradation pathways with the involvement several dechlorinated or hydroxylated metabolites were proposed for examined compunds. Concentration-dependent shifts in oxidative stress enzymes activity and slight modifications in phospholipid profiles were noted for the tested PBAT concentrations. In summary, this study enhances our understanding of PBAT's impact on the physiology of filamentous fungal and their degradative capacities important for mitigating environmental pollution by xenobiotics and plastics.

Plant Growth Promotion and Biological Control against Rhizoctonia solani in Thai Local Rice Variety "Chor Khing" Using Trichoderma breve Z2-03.

Several strains of Trichoderma are applied in the field to control plant diseases due to their capacity to suppress fungal pathogens and control plant diseases. Some Trichoderma strains also are able to promote plant growth through the production of indole-3-acetic acid (IAA). In southern Thailand, the local rice variety "Chor Khing" is mainly cultivated in the Songkhla province; it is characterized by slow growth and is susceptible to sheath blight caused by Rhizoctonia solani. Therefore, this research aimed to screen Trichoderma species with the ability to promote plant growth in this rice variety and enact biological control against R. solani. A total of 21 Trichoderma isolates were screened for indole compound production using the Salkowski reagent. The Z2-03 isolate reacted positively to the Salkowski reagent, indicating the production of the indole compound. High-performance liquid chromatography (HPCL) confirmed that Z2-03 produced IAA at 35.58 ± 7.60 μg/mL. The cell-free culture filtrate of the potato dextrose broth (CF) of Z2-03 induced rice germination in rice seeds, yielding root and shoot lengths in cell-free CF-treated rice that were significantly higher than those of the control (distilled water and culture broth alone). Furthermore, inoculation with Trichoderma conidia promoted rice growth and induced a defense response against R. solani during the seedling stage. Trichoderma Z2-03 displayed an antifungal capacity against R. solani, achieving 74.17% inhibition (as measured through dual culture assay) and the production of siderophores on the CAS medium. The pot experiment revealed that inoculation with the Trichoderma sp. Z2-03 conidial suspension increased the number of tillers and the plant height in the "Chor Khing" rice variety, and suppressed the percentage of disease incidence (PDI). The Trichoderma isolate Z2-03 was identified, based on the morphology and molecular properties of ITS, translation elongation factor 1-alpha (tef1-α), and RNA polymerase 2 (rpb2), as Trichoderma breve Z2-03. Our results reveal the ability of T. breve Z2-03 to act as a plant growth promoter, enhancing growth and development in the "Chor Khing" rice variety, as well as a biological control agent through its competition and defense induction mechanism in this rice variety.

Antagonistic potential of Trichoderma strains isolated from Musa paradisiaca cv. Malnad Rasbale grown farmyards against Foc race 4 pathogen

Foc race 4 is a causative pathogen for Panama wilt disease of Musa Paradisiaca cv. Malnad Rasbale. The cost-effective measure to control rather than the usage of agrochemicals is still not available for this cultivar. Trichoderma strains act as an antagonistic agent against different phytopathogenic fungi including many pathogenic races of Panama wilt-causing pathogens. An attempt has been made to recognize the mode of action of this antagonistic agent in in vitro conditions and interaction between six Trichoderma strains. Foc race 4 was first investigated by dual plate culture method on PDA medium. This study revealed the potential of native strain KUVKU-TH02 for the biological control of Foc race 4 pathogen affecting Malnad Rasbale cultivar in in vivo conditions rather than native isolates KUVKU-TH01, KUVKU-TV01 and KUVKU-TV02. Observations revealed the lysis of hyphal ending in inhibited colonies of the fungal pathogen. Pure culture of isolated fungal strains incubated on potato dextrose broth made a path to isolate DNA for identification and molecular characterization studies. Upon DNA sequencing, native isolates sequences were deposited to NCBI genebank to gain accession IDs. The phylogenetic tree built showed the evolutionary relationship between the isolates and also the potency of native biocontrol isolates against procured isolates.

Trichoderma carraovejensis: a new species from vineyard ecosystem with biocontrol abilities against grapevine trunk disease pathogens and ecological adaptation.

Trichoderma strains used in vineyards for the control of grapevine trunk diseases (GTDs) present a promising alternative to chemical products. Therefore, the isolation and characterization of new indigenous Trichoderma strains for these purposes is a valuable strategy to favor the adaptation of these strains to the environment, thus improving their efficacy in the field. In this research, a new Trichoderma species, Trichoderma carraovejensis, isolated from vineyards in Ribera de Duero (Spain) area, has been identified and phylogenetically analyzed using 20 housekeeping genes isolated from the genome of 24 Trichoderma species. A morphological description and comparison of the new species has also been carried out. In order to corroborate the potential of T. carraovejensis as a biological control agent (BCA), confrontation tests against pathogenic fungi, causing various GTDs, have been performed in the laboratory. The compatibility of T. carraovejensis with different pesticides and biostimulants has also been assessed. This new Trichoderma species demonstrates the ability to control pathogens such as Diplodia seriata, as well as high compatibility with powdered sulfur-based pesticides. In conclusion, the autochthonous species T. carraovejensis can be an effective alternative to complement the currently used strategies for the control of wood diseases in its region of origin.

The Effect of Combined Application of Biocontrol Microorganisms and Arbuscular Mycorrhizal Fungi on Plant Growth and Yield of Tomato (Solanum lycopersicum L.)

Sustainable plant production requires less use of synthetic chemicals in plant nutrition and protection. Microbial products are among the most promising substitutes for chemicals. With the increasing popularity and availability of such products, it has become obligatory to use different microbes together. The effect of this has been tested in several studies, but their results have sometimes been contradictory depending on the microbial strains tested and the mode of application. We tested the effect of two commercially available antagonists and Funneliformis mosseae alone and in combination on tomato. Mycorrhizal treatment increased plant growth and yield, both alone and combined with the antagonists; however, mycorrhizal root colonization was not influenced by the antagonist. This treatment also led to a slight decrease in the occurrence of Trichoderma spp. on tomato roots but did not impede the colonization of roots by the applied Trichoderma strain. Our result confirmed that Trichoderma asperellum (T34) and Streptomyces griseoviridis (K61) can be safely combined with arbuscular mycorrhizal fungi (AMF), namely with F. mosseae.

Allochthonous Trichoderma Isolates Boost Atractylodes lancea Herb Quality at the Cost of Rhizome Growth.

Atractylodes lancea is a perennial herb whose rhizome (AR) is a valuable traditional Chinese medicine with immense market demand. The cultivation of Atractylodes lancea faces outbreaks of root rot and deterioration in herb quality due to complex causes. Here, we investigated the effects of Trichoderma spp., well-known biocontrol agents and plant-growth-promoters, on ARs. We isolated Trichoderma strains from healthy ARs collected in different habitats and selected three T. harzianum strains (Th2, Th3 and Th4) with the strongest antagonizing effects on root rot pathogens (Fusarium spp.). We inoculated geo-authentic A. lancea plantlets with Th2, Th3 and Th4 and measured the biomass and quality of 70-day-old ARs. Th2 and Th3 promoted root rot resistance of A. lancea. Th2, Th3 and Th4 all boosted AR quality: the concentration of the four major medicinal compounds in ARs (atractylon, atractylodin, hinesol and β-eudesmol) each increased 1.6- to 18.2-fold. Meanwhile, however, the yield of ARs decreased by 0.58- to 0.27-fold. Overall, Th3 dramatically increased the quality of ARs at a relatively low cost, namely lower yield, showing great potential for practical application. Our results showed selectivity between A. lancea and allochthonous Trichoderma isolates, indicating the importance of selecting specific microbial patches for herb cultivation.

Trichoderma harzianum enhances root biomass production and promotes lateral root growth of soybean and common bean under drought stress

AbstractDrought stress (DS) is one of the main environmental stresses that determines crop productivity. It has been estimated that DS depresses over 40%–60% of soybean (Glycine max (L.) Merr.) and common bean (Phaseolus vulgaris L.) production worldwide, respectively. Although different agronomic strategies are sometimes implemented, the current goal in sustainable agriculture could involve the inoculation with native microorganisms to mitigate DS effects. A potential fungal candidate is Trichoderma, which is recognized as a ubiquitous soil inhabitant with growth‐promoting and biocontrol potentiality. However, its potential for mitigating the stress for water deficit is less well‐documented. Our objective was to evaluate the effect of inoculation with native Trichoderma harzianum strains on soybean and common bean growth under contrasting conditions of water availability. Seeds were independently inoculated (or not) with IB‐J15 and IB‐363 strains, and plants were submitted to DS or were kept under optimal irrigation (well‐watered, WW). In both legumes, the most evident effect after being inoculated was the modification of plant root architecture, the increase in root area and the development of lateral roots in plants under WW and DS conditions. In soybean, both Trichoderma strains had a positive inoculation response, both fresh and dry root biomass increased under WW, and remarkably under DS conditions. The main effect was an increase of about 110% in root dry weight under WW and, about 330% in DS in plants inoculated with IB‐J15 strain, meanwhile, plants inoculated with IB‐363 increased root dry weight 60% in WW and 177% in DS conditions. Notably in soybean, the inoculation with both Trichoderma strains increased the root area more than 70% in both WW and DS conditions. Common beans inoculated with IB‐363 under WW conditions, reached a positive inoculation responsiveness of around 247% in shoot dry weight biomass, and under WW both strains increased the root area more than 50%. Further, IB‐363 increased leaf area by 25% in WW and 72% in DS. Additionally, the in vitro co‐culture between both Trichoderma strains and nodulating Rhizobium etli and Bradyrhizobium japonicum E109 showed compatibility between microorganisms, since no inhibition of their growth was observed. We emphasize that plants inoculated with Trichoderma showed better resistance to water deficit, as seen by redistribution of photosynthates, prioritizing mainly, the development of the root system. © 2024 Association of Applied Biologists.

Genetic diversity and antagonistic properties of Trichoderma strains from the crop rhizospheres in southern Rajasthan, India

There are fewer studies on Trichoderma diversity in agricultural fields. The rhizosphere of 16 crops was analyzed for Trichoderma species in 7 districts of Rajasthan state of India. Based on DNA sequence of translation elongation factor 1α (tef-1α), and morphological characteristics, 60 isolates were identified as 11 species: Trichoderma brevicompactum, species in Harzianum clade identified as T. afroharzianum, T. inhamatum, T. lentiforme, T. camerunense, T. asperellum, T. asperelloides, T. erinaceum, T. atroviride, T. ghanense, and T. longibrachiatum. T. brevicompactum is the most commonly occurring strain followed by T. afroharzianum. No new species were described in this study. T. lentiforme, showed its first occurrence outside the South American continent. The morphological and cultural characteristics of the major species were observed, described, and illustrated in detail. The isolates were tested for their antagonistic effect against three soilborne plant pathogens fungi: Sclerotium rolfsii, Rhizoctonia solani, and Fusarium verticillioides in plate culture assays. One of the most potent strains was T. afroharzianum BThr29 having a maximum in vitro inhibition of S. rolfsii (76.6%), R. solani (84.8%), and F. verticillioides (85.7%). The potential strain T. afroharzianum BThr29 was also found to be efficient antagonists against soil borne pathogens in in vivo experiment. Such information on crop selectivity, antagonistic properties, and geographic distribution of Trichoderma species will be beneficial for developing efficient Trichoderma-based biocontrol agents.

Biotechnological tools for genetic improvement of Trichoderma

Trichoderma is a cosmopolitan fungus widely distributed around the world. The different uses of this beneficial fungus are varied in several industries, like agriculture, textile, and paper, including the pharmaceutical industry. The genus Trichoderma has other mechanisms of action, including the production of different enzymes and secreted secondary metabolites used in various industries. The genomes of different Trichoderma species have been sequenced to identify the mechanisms for producing several compounds. The advancement of multiple technologies has allowed the development of transformation tools for the genetic improvement of Trichoderma, thus increasing biomass, primary and secondary metabolites, and enzymes. Therefore, genetic modification aims to increase compound production in several Trichoderma strains. Characterization of Trichoderma through gene expression analysis is essential for biotechnology applications. It helps counteract one of the most challenging problems for agriculture today, including climate change and the appearance of pathogens that attack crops with high commercial and food demand. In conclusion, this review analyzes various strategies to improve Trichoderma strains genetically and their multiple applications in the agricultural, textile, paper, and pharmaceutical industries. As a recommendation for future studies with potential impact, the optimization of specific genetic modifications in Trichoderma strains is recommended to improve their adaptability and effectiveness in combating emerging challenges in agriculture, especially those linked to climate change. Investigating possible synergies between genetically modified Trichoderma strains and environmentally sustainable agricultural practices could contribute to developing solutions for crop protection and yield improvement.

Cultivating a greener future: Exploiting trichoderma derived secondary metabolites for fusarium wilt management in peas

This study aimed to identify efficient Trichoderma isolate(s) for the management of Fusarium wilt in peas. Four different pea germplasms (Sarsabz, Pea-09, Meteor and Supreme) were evaluated for resistance against Fusarium oxysporum in pot assay. Resistant germplasm exhibits a varying range of disease severity (23%) and percent disease index (21%), whereas susceptible and highly susceptible germplasm exhibit maximum disease severity (44–79%) and percent disease index (47–82%). The susceptible germplasm Meteor was selected for in vivo experiment. Five different Trichoderma spp. (Trichoderma koningii, T. hamatum, T. longibrachiatum, T. viride, and T. harzianum) were screened for the production of hydrolytic extracellular enzymes under in vitro. In-vitro biocontrol potential of Trichoderma spp. was assayed by percentage inhibition of dry mass of Fusarium oxysporum pisi (FOP) with Trichoderma spp. metabolite filtrate concentrations. Maximum growth inhibition was observed by T. harzianum (50–89%). T. harzianum metabolites in filtrate conc. (40%, 50%, and 60%) exhibited maximum reduction in biomass and were thus used for in vivo management of the disease. The pot experiment for in-vivo management also confirmed the maximum inhibition of FOP by T. harzianum metabolites filtrate at 60% by reducing disease parameters and enhancing growth, yield, and physiochemical and stress markers. Trichoderma strains led to an increase in chlorophyll and carotenoids (34-26%), Total phenolic 55%, Total protein content 60%, Total Flavonoid content 36%, and the increasing order of enzyme activities were as follows: CAT > POX > PPO > PAL in all treatments. These strains demonstrate excellent bio-control of Fusarium wilt in pea via induction of defense-related enzymes. The present work will help use Trichoderma species in disease management programme as an effective biocontrol agent against plant pathogens.

Decrypting biocontrol functions and application modes by genomes data of three Trichoderma Strains/Species

Trichoderma is an excellent biocontrol agent, but most Trichoderma genomes remained at the scaffold level, which greatly limits the research of biocontrol mechanism. Here, we reported the chromosome-level genome of Trichoderma harzianum CGMCC20739 (Tha739), T. asperellum CGMCC11653 (Tas653) and T. atroviride CGMCC40488 (Tat488), they were assembled into 7 chromosomes, genome size were 40 Mb (10,611 genes), 37.3 Mb (10,102 genes) and 36.3 Mb (9,896 genes), respectively. The positive selected genes of three strains were associated to response to stimulus, signaling transduction, immune system and localization. Furthermore, the number of transcription factors in Tha739, Tas653 and Tat488 strains had significant difference, which may contribute to the differential biocontrol function and stress tolerance. The genes related to signal transduction and gene clusters related to antimicrobial compounds in Tha739 were more than those in Tas653 and Tat488, which showed Tha739 may keenly sense other fungi and quickly secret antimicrobial compounds to inhibit other fungi. Tha739 also contained more genes associated to detoxification, antioxidant and nutrition utilization, indicating it had higher stress-tolerance to hostile environments. And the substrate for synthesizing IAA in Tha739 was mainly 3-indole acetonitrile and indole acetaldehyde, but in Tat488, it was indole-3-acetamide, moreover, Tha739 secreted more phosphatase and phytase and was more related to soil phosphorus metabolism, Tat488 secreted more urease and was more related to soil nitrogen metabolism. These candidate genes related to biocontrol function and stress-tolerance laid foundations for construction of functional strains. All above proved the difference in biocontrol function of Tha739, Tas653 and Tat488 strains, however, the defects in individual strains could be compensated for through Trichoderma-biome during the commercial application process of biocontrol Trichoderma strains.

Trichoderma fungi for the protection of greenhouse crops against oomycete Pythium sp.

Goal. To identify a highly virulent fungus Trichoderma Pers. ex Fr. to protect greenhouse crops from the pathogen Pythium sp.
 Methods. The objects of research were strains/isolates of Trichoderma sp. from the working collection of the laboratory. The pathogen Pythium sp. was isolated from mineral wool used in a hydroponic greenhouse. The pathogenicity of Pythium sp. was determined by infecting cucumber seedlings in a humid chamber at 24°C. To select active strains of Trichoderma against Pythium sp., their antagonistic activity was studied by the method of double cultures. On day 10, the inhibition rate of fungi by each other (%) was determined.
 Results. When determining the pathogenicity of the isolate Pythium sp. against cucumber seedlings on day 4, 100% death of all sprouts occurred. When studying the antagonism of Trichoderma and Pythium sp. fungi, a high growth rate of oomycete was observed in the control. In 50 h after sowing, the pathogen colonized the entire agar plate. However, in double cultures, Trichoderma fungi inhibited the growth of oomycete. On day 10, 4 strains: T. lignorum (syn. T. viride) CNMN-FD-14, T. asperellum, T. koningii and Trichoderma sp. 1K colonized the pathogen with an inhibition rate of 100%. Other Trichoderma fungi inhibited the pathogen by 83.5—94.1%.
 Conclusions. Trichoderma strains with high inhibitory activity can be used as a producer of a biological product for the protection of greenhouse crops from Pythium sp. oomycete.

Antagonistic properties against Fusarium sporotrichioides and glycosylation of HT-2 and T-2 toxins by selected Trichoderma strains

The present study assessed the ability of Trichoderma to combat F. sporotrichioides, focusing on their antagonistic properties. Tests showed that Trichoderma effectively inhibited F. sporotrichioides mycelial growth, particularly with T. atroviride strains. In co-cultures on rice grains, Trichoderma almost completely reduced the biosynthesis of T-2 and HT-2 toxins by Fusarium. T-2 toxin-α-glucoside (T-2-3α-G), HT-2 toxin-α-glucoside (HT-2-3α-G), and HT-2 toxin-β-glucoside (HT-2-3β-G) were observed in the common culture medium, while these substances were not present in the control medium. The study also revealed unique metabolites and varying metabolomic profiles in joint cultures of Trichoderma and Fusarium, suggesting complex interactions. This research offers insights into the processes of biocontrol by Trichoderma, highlighting its potential as a sustainable solution for managing cereal plant pathogens and ensuring food safety.

Trunk Injection Delivery of Biocontrol Strains of Trichoderma spp. Effectively Suppresses Nut Rot by Gnomoniopsis castaneae in Chestnut (Castanea sativa Mill.).

Gnomoniopsis castaneae is responsible for brown or chalky nut rot in sweet chestnut (Castanea sativa), causing heavy reductions in nut production. Controlling it is challenging, due to its inconspicuous infections, erratic colonization of host tissues and endophytic lifestyle. Fungicides are not applicable because they are prohibited in chestnut forests and strongly discouraged in fruit chestnut groves. Trichoderma species are safe and wide-spectrum biocontrol agents (BCAs), with a variety of beneficial effects in plant protection. This study tested selected strains of T. viride, T. harzianum and T. atroviride for their ability to suppress G. castaneae. Field experiments were conducted in four chestnut groves (two test plots plus two controls) at two sites with a different microclimate. As the size of the trees were a major drawback for uniform and effective treatments, the Trichoderma strains were delivered directly by trunk injection, using the BITE® (Blade for Infusion in TrEes) endotherapic tool. The BCA application, repeated twice in two subsequent years, significantly reduced nut rot incidence, with a more marked, presumably cumulative, effect in the second year. Our data showed the tested Trichoderma strains retain great potential for the biological control of G. castaneae in chestnut groves. The exploitation of Trichoderma spp. as biopesticides is a novelty in the forestry sector and proves the benefits of these microbes in plant disease protection.

Trichoderma spp. promotes ginseng biomass by influencing the soil microbial community.

Ginseng (Panax ginseng C.A. Meyer) has multiple effects on human health; however, soil degradation seriously affects its yield. Trichoderma spp. play an important role in improving plant biomass by influencing the soil environment. Therefore, it is necessary to screen efficient Trichoderma strains that can increase ginseng biomass and determine their mechanisms. Herein, we selected six Trichoderma species (T. brevicompactum, T. velutinum, T. viridescens, T. atroviride, T. koningiopsis, and T. saturnisporum) isolated from ginseng rhizosphere soil, and evaluated their growth promoting effects on ginseng and their influence on the microbiome and chemical attributes of the ginseng rhizosphere soil. Except for T. saturnisporum (F), compared with the control, the other five species increased ginseng biomass. In terms of chemical properties, the pH value, available potassium content, and available phosphorus content in the ginseng rhizosphere soil increased by 1.16-5.85%, 0.16-14.03%, and 3.92-38.64%, respectively, after root irrigation with spores of Trichoderma species. For the soil microbiome, fungal Chao1 and Ace richness indices decreased. Application of Trichoderma enhanced the relative level of Proteobacteria, but reduced the relative level of Ascomycota. At the genus level, application of Trichoderma enhanced the relative levels of Sphingomonas, Blastomonas, and Trichoderma, but reduced the relative level of Fusarium. Available K and available P were the most important elements that affected the structure of the bacterial community, while total K was the most influential element for the structure of the fungal community structure. The results indicated that the application of Trichoderma spp. could increase soil nutrients and regulate the structure and composition of the soil microbial community, thereby enhancing the biomass of ginseng. The results will provide guidance for soil improvement in ginseng cultivation.

Enhancing Stability and Efficacy of Trichoderma Bio‐Control Agents Through Layer‐by‐Layer Encapsulation for Sustainable Plant Protection

AbstractAgricultural fungicide pollution poses a significant environmental challenge and causes adverse effects on human health. Therefore, strategies to limit fungicide usage are of paramount importance. Trichoderma fungi, due to their antagonistic activity against various pathogenic fungi, have shown potential as a sustainable alternative to chemical fungicides. However, bio‐control agents like Trichoderma are vulnerable to physical stimuli and show diminished efficacy during prolonged storage. To address these challenges, a mild and scalable encapsulation method for Trichoderma spores is introduced, employing a layer‐by‐layer (LbL) approach using biobased lignin derivatives. It is demonstrated that the LbL encapsulation technique significantly improved spore stability relative to naked spores, even under adverse conditions including extreme temperatures and prolonged exposure to Ultraviolet (UV) irradiation. Notably, encapsulated Trichoderma spores showed enhanced efficacy in cultivating tomato plants compared to naked spores. Additionally, the findings revealed that the in planta efficacy of encapsulated spores is dependent on the specific Trichoderma strain used. This study suggests that Trichoderma spores encapsulated with lignin through the LbL approach, are a promising and sustainable alternative to chemical fungicides with potential for commercialization.

Biological control of root-knot nematodes in common beans using putative nematocidal species of Trichoderma indigenous to Pakistan

ABSTRACT The putative nematocidal strains of Trichoderma for controlling root-knot nematodes were isolated from different agricultural fields in Pakistan. The Trichoderma isolates were confirmed using morphological and molecular characterisation. The root-knot nematodes were isolated from infected common bean plants Phaseolus vulgaris and identified as Meloidogyne incognita through phenotypic characteristics. Both in vitro and in vivo assays were performed. The nematocidal activity of the selected Trichoderma spp. was assessed using culture filtrate and spore suspension assays. Parameters including J2 mortality, egg hatching inhibition, root gall index, and egg mass index were calculated. The culture filtrates of T. bevicrassum strain ISO-03 caused significantly higher J2 mortality (71%) and inhibited egg hatching (68%) as compared to the activities of culture filtrates of the other two strains used in this study. The least control activity was observed in case of the culture filtrates of T. viride strain ISO-05 with 21% J2 mortality and 19% egg hatching inhibition. Similarly, the spore suspensions of T. brevicrassum ISO-03 showed the highest mortality of M. incognita juveniles (64% with respect to control) as well as the egg-hatching inhibition rates of 59%. In the in vivo study, the same strain T. bevicrassum ISO-03 significantly reduced the root galling index and egg mass indices as compared to the control. Furthermore, T. bevicrassum ISO-03 significantly promoted plant growth compared to the control. Overall, T. bevicrassum ISO-03 was identified as a potent biocontrol strain against root-knot nematodes in addition to its plant growth-promoting characteristics.

Screening and evaluation of the biocontrol efficacy of a Trichoderma brevicompactum strain and its metabolite trichodermin against banana Fusarium wilt

The banana Fusarium wilt (BFW) caused by Fusarium oxysporum f. sp. cubense tropical race4 (FocTR4) is difficult to control worldwide, which causes a huge economic losse to banana industry. The purpose of this study was to screen Trichoderma strains with antagonistic activity against FocTR4, to isolate and purify the active compound from the fermentation broth, so as to provide important biocontrol strains and active compound resources. In this work, Trichoderma strains were isolated and screened from the rhizosphere soil of crops, and the strains capable of efficiently inhibiting FocTR4 were screened by plate confrontation, and further confirmed by testing inhibition for the conidial germination and mycelial growth of FocTR4. The phylogenetic tree clarified the taxonomic status of the biocontrol strains. Moreover, the active components in the fermentation broth of the strains were separated and purified by column chromatography, the structure of the most active component was analyzed by nuclear magnetic resonance spectroscopy (NMR), the BFW control effect was tested by pot experiments. We obtained a strain JSHA-CD-1003 with antagonistic activity against FocTR4, and the inhibition rate from plate confrontation was 60.6%. The fermentation broth of JSHA-CD-1003 completely inhibited the germination of FocTR4 conidia within 24 hours. The inhibition rate of FocTR4 hyphae growth was 52.6% within 7 d. A phylogenetic tree was constructed based on the ITS and tef1-α gene tandem sequences, and JSHA-CD-1003 was identified as Trichoderma brevicompactum. Purification and NMR identification showed that the single active compound was trichodermin, and the minimum inhibitory concentration (MIC) was 25 μg/mL. Pot experiments showed that the fermentation broth of strain JSHA-CD-1003 was effective against BFW. The control rate of leaf yellowing was 47.4%, and the rate of bulb browning was 52.0%. Therefore, JSHA-CD-1003 effectively inhibited FocTR4 conidial germination and mycelium growth through producing trichodermin, and showed biocontrol effect on banana wilt caused by FocTR4, thus is a potential biocontrol strain.

Newly Isolated Trichoderma spp. Show Multifaceted Biocontrol Strategies to Inhibit Potato Late Blight Causal Agent Phytophthora infestans both In Vitro and In Planta

Potato growers worldwide have been at war for more than 150 years with an enemy whose lifecycle, genome size and architecture, infection rate, and economic impacts are the epitome of a plant pathogen. Phytophthora infestans is an oomycete that causes the notorious late blight infection in potato and tomato fields. This study explored the benefits of the multitalented plant symbiotic fungi Trichoderma spp. and their metabolites as potential biopesticides against P. infestans. Eleven strains of Trichoderma spp. were obtained from soil and tree barks and were identified using DNA sequence analysis of three molecular markers. The antagonistic potential of the strains against P. infestans was first evaluated in vitro. In dual-culture assays, P. infestans growth was significantly inhibited (53 to 95%) by different Trichoderma spp. through direct mycoparasitism, competition for space and nutrients, or antibiosis. The cell-free filtrates (CFFs) of different Trichoderma strains were obtained and characterized for anti- Phytophthora activities as well as biochemical stability. The obtained results indicated that Trichoderma CFFs were chemically stable and strongly decreased P. infestans’ mycelial growth and zoospore motility and viability. Similarly, in leaf-disk assays, Trichoderma CFFs showed significant protection against P. infestans infection. Ultraperformance liquid chromatography analysis revealed the presence of harzianic acid, iso-harzianic acid, and 6-pentyl-2H-pyran-2-one as major compounds in different Trichoderma CFFs. Furthermore, selected Trichoderma strains significantly protected potato plants against soil-mediated late blight infection. Finally, Trichoderma spp. showed high compatibility with a copper-based fungicide, especially at lower concentrations, suggesting that both protective agents could be combined in integrated pest management programs. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .