Trichoderma Isolates Research Articles

Isolation, screening, and molecular characterization of indigenous Trichoderma isolates from West Java, Indonesia and their plant growth-promoting capability on rice plants (Oryza sativa L.)

Trichoderma species are widely acknowledged as growth-promoting fungi that have been utilized to enhance the growth and yield of numerous crops. This research examined the capacity of 30 Trichoderma strains, isolated from two organic rice fields in West Java, Indonesia, to enhance the germination, growth, and physiological characteristics of rice plants (Oryza sativa L.). In general, Trichoderma strain TM10 demonstrated the greatest ability to increase seed germination (97.25 %), vigor index (3122.83), and germination speed (59.91 seeds/day). This strain also increased seedling root length and seedling height by 101.62 % and 112.20 %, respectively. Plants treated with TM10 exhibited a notable improvement in root length, plant height, fresh weight, and dry weight compared to control plants, demonstrating increases of 188.68 %, 69.90 %, 157.41 %, and 159.38 %, respectively. Furthermore, the total chlorophyll content and stomatal number in TM10-treated plants exhibited increments of 75.23 % and 75.53 %, respectively. Five selected isolates (TM7, TM10, SB2, SB8, and SB14) were evaluated for their potential to produce plant growth-promoting compounds, including phosphatase enzyme (ranging from 0.54 to 11.14 µg pNP g−1h−1), indole-3-acetic acid (IAA) (ranging from 28.96 to 63.91 µg/mL), ammonia (ranging from 1.96 to 5.79 µg/mL), and hydrogen cyanide (HCN) (ranging from 221.76 to 274.82 ppm). The best strain, namely TM10, was then molecularly identified as Trichoderma yunnanense. This investigation demonstrates that Trichoderma spp. isolated from organic rice fields could be used as a bioinoculant in sustainable rice production.

Impact of Trichoderma afroharzianum infection on fresh matter content and grain quality in maize.

Trichoderma afroharzianum, a ubiquitous soil-borne fungus found on plant roots and decaying residues, displays competitive traits and mycoparasitic behavior against diverse microorganisms. Selected strains of this fungus are known in agriculture for their beneficial effects on plant growth and as bio-fungicides. However, recent findings have pinpointed Trichoderma afroharzianum as the causal agent behind maize ear rot disease in Europe since 2018, notably impacting maize cobs in Germany, France, and Italy. This study aims to evaluate the severity of Trichoderma ear rot disease on maize fresh matter content and specific quality parameters under semi-field conditions. Two distinct maize varieties were artificially inoculated with a pathogenic Trichoderma isolate at the flowering stage using needle pin or silk channel methods. Disease severity was assessed visually at the time of harvest based on the percentage of infected kernels according to EPPO Guidelines (PP 1/285). Fresh matter content and quality parameters such as alpha-amylase activity, C/N ratio, water, and sugar content were analyzed. Results showed that needle pin inoculation led to higher disease severity (60%) compared to silk channel inoculation (39%). Cob weight decreased significantly at the highest disease severity level by up to 50% compared to control plants. In both varieties, alpha-amylase activity increased significantly with higher Trichoderma disease severity, resulting in starch degradation and increased glucose release. The germination rate was severely affected by the infection, with only 22% of grains germinating, and the seedlings showed shortened and deformed growth. This is the first report on Trichoderma ear rot infection and its effect on fresh matter content and quality parameters in maize after artificial inoculation under field conditions. The results address an important knowledge gap and provide valuable insights into the infection pathway and impact on maize quality.

Screening of the Biocontrol Efficacy of Potent Trichoderma Strains against Fusarium oxysporum f.sp. ciceri and Scelrotium rolfsii Causing Wilt and Collar Rot in Chickpea.

Chickpeas contribute to half of the pulses produced in India and are an excellent source of protein, fibers, carbohydrates, minerals, and vitamins. However, the combination of the wilt and root rot diseases drastically lowers its yield. The use of antagonist microbes that restrict the growth of other phytopathogens is an ecofriendly approach to combat the serious threats raised by the plant pathogens. Trichoderma spp. are well known as biocontrol agents, especially against soil- and seed-borne phytopathogens. In this study, 21 Trichoderma isolates that were collected from different rhizospheric soils were evaluated against two notorious soil-borne pathogens, such as Fusarium oxysproum f.sp. ciceri and Sclerotium rolfsii. The maximum percentage of inhibition against the tested pathogens was observed in Trichoderma isolate PBT13 (72.97%, 61.1%) followed by PBT3 (72.23%, 59.3%). The mycelial extension rate method, dual culture (antagonism), production of cell-wall degrading enzymes (CWDs), and antifungal metabolites (by GC-MS) were used as selection criteria for potent Trichoderma isolates. Among the 21 isolates, PBT3, PBT4, PBT9, and PBT13 exhibited high antagonistic activity, production of antifungal metabolites, and chitinase and β-1,3-glucanase activity. These four species were subjected to molecular characterization using an internal transcribed spacer (ITS 1 and ITS4). The results of molecular characterization identified the four species as T. virnes, T. asperellum, T. lixii, and T. harzianum. Moreover, significant chitinase and β-1,3-glucanase activities of all Trichoderma isolates were recorded in the growth medium. Trichoderma harzianum (isolate PBT13) was found to exhibit the highest chitinase activity in terms of zone formation (4.40 ± 0.17 cm), whereas Trichoderma virens (isolate PBT3) exhibited the highest β-1,3-glucanase activity1.511 μmole/min. A GC-MS analysis of ethyl extracts from two isolates of Trichoderma (PBT9, PBT13) revealed the presence of 28 VOCs. Overall, this study suggests that these four Trichoderma strains are promising biological control agents (BCAs) and could be developed as bio-pesticides after stringent field trials for the management of soil-borne diseases of chickpeas.

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.

Biocontrol of strawberry Botrytis gray mold and prolong the fruit shelf-life by fumigant Trichoderma spp.

Objectives To screen high active volatile organic compounds (VOCs)-producing Trichoderma isolates against strawberry gray mold caused by Botrytis cinerea, and to explore their antagonistic mode of action against the pathogen. VOCs produced by nine Trichoderma isolates (Trichoderma atroviride T1 and T3; Trichoderma harzianum T2, T4 and T5; T6, T7, T8 and T9 identified as Trichoderma asperellum in this work) significantly inhibited the mycelial growth (13.9-63.0% reduction) and conidial germination (17.6-96.3% reduction) of B. cinerea, the highest inhibition percentage belonged to VOCs of T7; in a closed space, VOCs of T7 shared 76.9% and 100% biocontrol efficacy against gray mold on strawberry fruits and detached leaves, respectively, prolonged the fruit shelf-life by 3 days in presence of B. cinerea, completely protected the leaves from B. cinerea infecting; volatile metabolites of T7 damaged the cell membrane permeability and integrity of B. cinerea, thereby inhibiting the mycelial growth and conidial germination. Gas chromatography-mass spectrometry (GC-MS) analysis revealed the VOCs contain 23 potential compounds, and the majority of these compounds were categorised as alkenes, alcohols, and esters, including PEA and 6PP, which have been reported as substances produced by Trichoderma spp. T. asperellum T7 showed high biofumigant activity against mycelial growth especially conidial germination of B. cinerea and thus protected strawberry fruits and leaves from gray mold, which acted by damaging the pathogen's plasma membrane and resulting in cytoplasm leakage, was a potential biofumigant for controlling pre- and post-harvest strawberry gray mold.

In vitro study of Trichoderma isolates – potential antagonists of Sclerotinia sclerotiorum and other soil pathogens causing root and stem rots on pepper (Capsicum annuum L.)

White mold Sclerotinia sclerotiorum (Lib.) de Bary is a potentially serious disease of pepper (Capsicum annuum L.) grown in unheated greenhouses. Control of Sclerotinia sclerotiorum is difficult due to lack of Capsicum spp. resistance towards this pathogen. Currently, among the registered fungicides there is none that can combat this pepper disease. The isolation and selection of local strains of antagonistic microbes is part of the strategy to combat pathogens by means of alternative methods. In vitro studies have been carried out on soil isolates of Trichoderma spp. regarding their antagonistic activity on the pathogen Sclerotinia sclerotiorum. All isolates were found to have a higher ability to compete with the phytopathogen for the food substrate. The competitive ability coefficient of Trichoderma spp. isolates varies widely – from 1.2 to 11. Among them, an isolate with pronounced antagonistic activity and a competitive ability coefficient of 10.8 stands out. The isolated fungus was identified as Trichoderma viride based on the cultural and morphological characteristics. The isolated strain was found to have high in vitro antagonistic activity not only against Sclerotinia sclerotiorum but also against various pathogens causing root and stem rot of pepper such as Botrytis cinerea, Verticillium dahliae and Rhizoctonia solani. The results of the current study showed that Trichoderma viride (Trv) has the potential to be used for production of biopreparation intended to control Sclerotinia sclerotiorum and other soil-borne pathogens in greenhouses. Keywords: antagonistic fungi, in vitro screening, antifungal activity, biological control, white mold, Capsicum annuum

Trichoderma spp. isolates stimulate rice seedling growth of Sertani 13 variety

Trichoderma has become one of the most studied filamentous fungi to be used as a greener and more sustainable solution for improving the production and growth of numerous crops, due to its capability to form symbiotic associations with plants. This study aimed to evaluate the effect of Trichoderma isolates obtained from the rhizosphere of organic rice fields in Sukabumi, Indonesia, in enhancing rice germination and seedling growth. A laboratory experiment used a completely randomized design consisting of seed treatments of 21 Trichoderma isolates (T1-T21) and a control treatment without Trichoderma (C). The inoculation was employed to elucidate any potential effects of Trichoderma isolates. Results showed that five isolates, i.e., T5, T7, T9, T10, and T14 stimulated the highest seedling vigor index, root and shoot length, and fresh weight and dry weight. These findings exhibited the potential of these five isolates as plant growth-promoting fungi to improve rice seedling growth and contribute to our understanding of the role of symbiotic fungi in sustainable rice crop production. Keywords: plant growth promoting fungi; seed treatment; plant-microbe interactions, symbiotic fungi

Kinetic studies on optimized extracellular laccase from Trichoderma harzianum PP389612 and its capabilities for azo dye removal

BackgroundAzo dyes represent a common textile dye preferred for its high stability on fabrics in various harsh conditions. Although these dyes pose high-risk levels for all biological forms, fungal laccase is known as a green catalyst for its ability to oxidize numerous dyes.MethodsTrichoderma isolates were identified and tested for laccase production. Laccase production was optimized using Plackett–Burman Design. Laccase molecular weight and the kinetic properties of the enzyme, including Km and Vmax, pH, temperature, and ionic strength, were detected. Azo dye removal efficiency by laccase enzyme was detected for Congo red, methylene blue, and methyl orange.ResultsEight out of nine Trichoderma isolates were laccase producers. Laccase production efficiency was optimized by the superior strain T. harzianum PP389612, increasing production from 1.6 to 2.89 U/ml. In SDS-PAGE, purified laccases appear as a single protein band with a molecular weight of 41.00 kDa. Km and Vmax values were 146.12 μmol guaiacol and 3.82 μmol guaiacol/min. Its activity was stable in the pH range of 5–7, with an optimum temperature range of 40 to 50 °C, optimum ionic strength of 50 mM NaCl, and thermostability properties up to 90 °C. The decolorization efficiency of laccase was increased by increasing the time and reached its maximum after 72 h. The highest efficiency was achieved in Congo red decolorization, which reached 99% after 72 h, followed by methylene blue at 72%, while methyl orange decolorization efficiency was 68.5%.ConclusionTrichoderma laccase can be used as an effective natural bio-agent for dye removal because it is stable and removes colors very well.

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.

Biodiversity of Trichoderma species of healthy and Fusarium wilt-infected banana rhizosphere soils in Tenerife (Canary Islands, Spain).

Banana (Musa acuminata) is the most important crop in the Canary Islands (38.9% of the total cultivated area). The main pathogen affecting this crop is the soil fungal Fusarium oxysporum f. sp. cubense subtropical race 4 (Foc-STR4), for which there is no effective control method under field conditions. Therefore, the use of native biological control agents may be an effective and sustainable alternative. This study aims to: (i) investigate the diversity and distribution of Trichoderma species in the rhizosphere of different banana agroecosystems affected by Foc-STR4 in Tenerife (the island with the greatest bioclimatic diversity and cultivated area), (ii) develop and preserve a culture collection of native Trichoderma species, and (iii) evaluate the influence of soil chemical properties on the Trichoderma community. A total of 131 Trichoderma isolates were obtained from 84 soil samples collected from 14 farms located in different agroecosystems on the northern (cooler and wetter) and southern (warmer and drier) slopes of Tenerife. Ten Trichoderma species, including T. afroharzianum, T. asperellum, T. atrobrunneum, T. gamsii, T. guizhouense, T. hamatum, T. harzianum, T. hirsutum, T. longibrachiatum, and T. virens, and two putative novel species, named T. aff. harzianum and T. aff. hortense, were identified based on the tef1-α sequences. Trichoderma virens (35.89% relative abundance) and T. aff. harzianum (27.48%) were the most abundant and dominant species on both slopes, while other species were observed only on one slope (north or south). Biodiversity indices (Margalef, Shannon, Simpson, and Pielou) showed that species diversity and evenness were highest in the healthy soils of the northern slope. The Spearman analysis showed significant correlations between Trichoderma species and soil chemistry parameters (mainly with phosphorus and soil pH). To the best of our knowledge, six species are reported for the first time in the Canary Islands (T. afroharzianum, T. asperellum, T. atrobrunneum, T. guizhouense, T. hamatum, T. hirsutum) and in the rhizosphere of banana soils (T. afroharzianum, T. atrobrunneum, T. gamsii, T. guizhouense, T. hirsutum, T. virens). This study provides essential information on the diversity/distribution of native Trichoderma species for the benefit of future applications in the control of Foc-STR4.

Genetic Improvement of Some Trichoderma Isolates for Second-Generation Biofuel Production from Agricultural Wastes.

Genetic Improvement of Some Trichoderma Isolates for Second-Generation Biofuel Production from Agricultural Wastes.

Biocontrol Potential of Trichoderma Ghanense and Trichoderma Citrinoviride toward Pythium aphanidermatum.

Pythium-induced damping-off of cucumber is a major constraint to cucumber production in different parts of the world. Although chemical fungicides are used for managing this disease, they have many drawbacks to the environment. The ability of the antagonistic fungi isolated from the rhizosphere and endosphere of Dactyloctenium robecchii and Moraea sisyrinchium in the control of soilborne pathogen Pythium aphanidermatum was inspected. Native Trichoderma isolates, Trichoderma ghanense and Trichoderma citrinoviride, were isolated from plant stem and soil samples collected from Al-Seeb, Oman. Using a dual culture technique, the antagonistic activity of the fungal isolates against P. aphanidermatum was examined in vitro. Among Trichoderma isolates, T. ghanense was more efficient in restraining the mycelial growth of P. aphanidermatum, causing an inhibition percentage of 44.6%. Further, T. citrinoviride induced significantly lower cessation of P. aphanidermatum mycelial growth (31.3%). Microscopic and electrolyte leakage inspection of the pathogen mycelia depicted extreme morphological malformations in their mycelium, which can be attributed to the antifungal metabolites of antagonists. Greenhouse studies demonstrated the effectivity of T. ghanense in controlling Pythium damping-off of cucumber plants, where the number of surviving plants was over 90% when the biocontrol agents were used compared to 0 in the control plants. Furthermore, treatment of the plants with the antagonists promoted growth characteristics of plants compared to uninoculated plants. This included improvements in shoot and root lengths, leaf length and width, and dry weight. These findings suggest that T. ghanense and T. citrinoviride can be developed as alternatives to synthetic chemical fungicides to manage soilborne pathogens of cucumber. This research is also the first to clarify the biocontrol ability of T. citrinoviride and T. ghanense against cucumber damping-off caused by P. aphanidermatum.

Internal Transcribed Spacers (ITS) Based Identification of Trichoderma Isolates and Biocontrol Activity against Fusarium oxysporum and Chitinase Activity

Twelve Trichoderma spp. isolated from different locations in Uttar Pradesh, India. Internal transcribed spacer (ITS) amplification and sequencing were used to identify isolates of Trichoderma that showed 99–100% identification with Trichoderma harzianum, Trichoderma asperellum, and Trichoderma longibrachiatum, the three species of Trichoderma. Tests were conducted in Vitro to evaluate the biocontrol potential of Trichoderma isolates against Fusarium species. After seven days of incubation, the isolate TBT6 (T. harzianum) exhibited the greatest antagonism against Fusarium oxysporum, with inhibition rates of 87.1%) by TBT7 (82.2%), and the least amount of inhibition (59.7%) by T. longibrachiatum isolate TBT10. Under field conditions, the antagonistic T. harzianum isolate TBT6 can be employed as a bio-control agent against Fusarium oxysporum. and for the development of formulations based on Trichoderma. Using the dual plate approach, twelve highly antagonistic Trichoderma isolates were selected for chitinolytic activity. Observing the breakdown of chitin substrates, Trichoderma isolates TBT6 was shown to have strong chitinolytic enzyme activity, making it a good candidate for endochitinase gene isolation. Using two particular primers, the genomic DNA of the Trichoderma isolate TBT6 was isolated and amplified.

Trichoderma atrobrunneum: In vitro analysis of exoenzyme activity and antagonistic potential against plant pathogen from agricultural fields in the Patna region, India

Background: Fungi and oomycetes continue to be the primary source of plant diseases, which cause major crop loss factors in agriculture. Trichoderma is a genus of ascomycete fungus that lives in soil and is known for its ecological significance as a bio-fungicide. Aim: The current study aimed to assess and contrast the antagonism and exoenzyme activity of Trichoderma isolates against Pythium sp., which causes damping-off and root rot diseases on tomato plants. Trichoderma spp. was isolated from rhizospheric soil of healthy plants in the agricultural fields of Patna, Bihar district, India. Methodology: The Trichoderma isolates were evaluated for their suitability as antagonists by in vitro dual culture and non-volatile assay. Results: The results showed that the isolated Trichoderma species were effectively reduced the growth of Pythium sp. in the dual culture assay and non-volatile metabolites (12.5%, 25% and 50% v/v concentration) assay. Trichoderma atrobrunneum effectively inhibited the mycelial growth of Pythium sp. both in the dual culture (81.48%) and non-volatile metabolite assay (71.37%). Followed by Trichoderma harzianum (79.01% and 58.82%), and Trichoderma asperellum (65.43% and 50.58%) respectively. Exoenzyme activities of the Trichoderma isolates were also investigated. The antagonistic Trichoderma atrobrunneum exhibited maximum activities of β-1,3-glucanase (41.39 U/ml) and chitinase (33.06 U/ml) in comparison to T. harzianum and T. asperellum. The capacity of antagonism is enhanced by the production of the enzyme. Based on the above results, it can be said that the non-volatile metabolites and the exoenzyme of the antagonist T. species act synergistically in inhibiting Pythium growth. Conclusion: The secretion of enzymes by Trichoderma species shows that they can be used in plant disease control as novel biocontrol agents as well as to produce enzymes in biotechnological processes.

Strain-specific and sensitive monitoring of the biocontrol agent Trichoderma asperellum T34 in growing medium via real-time PCR

ABSTRACT Trichoderma asperellum Samuels, Lieckf. & Nirenberg is one of several Trichoderma species comprising effective biocontrol strains. One of these, Trichoderma asperellum T34, shows activity against soilborne pathogens such as Rhizoctonia, Fusarium, and Pythium. The activity of biocontrol strains such as T34 depends on their establishment in the rhizosphere. Monitoring of the population of T34 and other strains in the rhizosphere and the growing medium is therefore important for evaluating their potential in different crops and different growing systems. Until now, strain-specific monitoring has been very difficult as the main quantification methods, i.e. traditional dilution plating or standard molecular detection methods, are specific only at genus or species level, respectively. Genotyping-by-sequencing was used to identify genomic loci specific to T34. These were used to develop strain-specific Taqman real-time (qPCR) assays. After testing for specificity and sensitivity, two assays were combined in duplex format. The duplicate assay provided an internal control to avoid a false positive signal in case one of the target loci would be present in an as yet unidentified non-target organism. An optional enrichment step in semi-selective medium was included for increased sensitivity in cases of small T34 population size, theoretically allowing detection down to 0.1 spore equivalent per mL growing medium. The techniques were applied to 200 mL samples of growing medium analyzed 0, 19, and 112 days after spiking with different numbers and combinations of spores from target and non-target Trichoderma isolates. This technique shows potential for developing other strain-specific detection assays using an affordable genotyping tool.

Evaluation of Trichoderma spp. as a plant growth promoter and antagonist of major pulse pathogens

Trichoderma spp. is mostly used for the management of soil-borne diseases and some foliage and fruit diseases in a variety of crop plants. It can help the environment by reducing agrochemical pollution, promoting plant growth, and enhancing plant resistance in addition to preventing plant diseases. Trichoderma spp. also functions as a secure, affordable, efficient, and environmentally friendly biocontrol agent for several crop species. In the present study, we obtained different Trichoderma isolates from rhizospheric soil samples of different locations and tested them for their antagonistic activity against major pulse pathogens. Among seven isolates, three isolates, viz., Pipal TH-2, ATH-Kashipur, and Mz/AP-2 were found to be highly effective by inhibiting the growth of Fusarium udum (64.04 to 78.65%), Fusarium ciceris (77.77 to 82.12%), Sclerotium rolfsii (59.09 to 69.30%), Macrophomina phaseolina (52.42 to 62.72%) and Alternaria alternata (80.12 to 83.22%). These isolates were also tested for growth-promoting traits (PGPR) in the present study and isolates having both plant growth-promoting ability and biocontrol potentiality were selected and preserved for further studies. These isolates of Trichoderma spp. would be a crucial partner for achieving the Green Earth goal due to their contribution to the sustainable growth of agriculture.

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.

In vitro evaluation of the inhibitory capacity of three Trichoderma isolates on Ralstonia solanacearum

Bacterial wilt in bananas, caused by Ralstonia solanacearum or Moko, limits crop production and threatens Ecuador. This study evaluated Trichoderma isolates in laboratory conditions as an innovative alternative to ensure sustainability in banana production. The four R. solanacearum. isolates were obtained from banana plants exhibiting disease symptoms and were characterized through morphological and biochemical tests. Four treatments were evaluated: three isolates of fungi from the genus Trichoderma (Trichoderma viride, T. harzianum, T. asperellum) and one consisting of a combination of the three isolates above. The inhibitory capacity of the Trichoderma isolates on R. solanacearum colonies was measured. A completely randomized design with three replicates was used, and general linear and mixed models were employed, with qq-plot graphs for normality and residual plots for variance homogeneity. Furthermore, a Fisher's LSD test was conducted at a significance level of α = 0.05. In the biochemical tests, the bacterial isolates exhibited specific characteristics of R. solanacearum in two bacterial isolates. In the inhibition tests, treatment four and treatment one (consortium of the three Trichoderma isolates and Trichoderma viride) showed the highest inhibitory potential, with 76.07% and 61.19%, respectively. The consortium of Trichoderma isolates demonstrated the highest inhibitory potential against R. solanacearum, with day 10 being the time with the highest percentage of inhibition (72.61%). Keywords: Bacterial wilt, Ralstonia solanacearum, Trichoderma, inhibition

In vitro evaluation of the inhibitory capacity of three Trichoderma isolates on Ralstonia solanacearum

Bacterial wilt in bananas, caused by Ralstonia solanacearum or Moko, limits crop production and threatens Ecuador. This study evaluated Trichoderma isolates in laboratory conditions as an innovative alternative to ensure sustainability in banana production. The four R. solanacearum. isolates were obtained from banana plants exhibiting disease symptoms and were characterized through morphological and biochemical tests. Four treatments were evaluated: three isolates of fungi from the genus Trichoderma (Trichoderma viride, T. harzianum, T. asperellum) and one consisting of a combination of the three isolates above. The inhibitory capacity of the Trichoderma isolates on R. solanacearum colonies was measured. A completely randomized design with three replicates was used, and general linear and mixed models were employed, with qq-plot graphs for normality and residual plots for variance homogeneity. Furthermore, a Fisher's LSD test was conducted at a significance level of α = 0.05. In the biochemical tests, the bacterial isolates exhibited specific characteristics of R. solanacearum in two bacterial isolates. In the inhibition tests, treatment four and treatment one (consortium of the three Trichoderma isolates and Trichoderma viride) showed the highest inhibitory potential, with 76.07% and 61.19%, respectively. The consortium of Trichoderma isolates demonstrated the highest inhibitory potential against R. solanacearum, with day 10 being the time with the highest percentage of inhibition (72.61%). Keywords: Bacterial wilt, Ralstonia solanacearum, Trichoderma, inhibition

In vitro evaluation of the inhibitory capacity of three Trichoderma isolates on Ralstonia solanacearum

Bacterial wilt in bananas, caused by Ralstonia solanacearum or Moko, limits crop production and threatens Ecuador. This study evaluated Trichoderma isolates in laboratory conditions as an innovative alternative to ensure sustainability in banana production. The four R. solanacearum. isolates were obtained from banana plants exhibiting disease symptoms and were characterized through morphological and biochemical tests. Four treatments were evaluated: three isolates of fungi from the genus Trichoderma (Trichoderma viride, T. harzianum, T. asperellum) and one consisting of a combination of the three isolates above. The inhibitory capacity of the Trichoderma isolates on R. solanacearum colonies was measured. A completely randomized design with three replicates was used, and general linear and mixed models were employed, with qq-plot graphs for normality and residual plots for variance homogeneity. Furthermore, a Fisher's LSD test was conducted at a significance level of α = 0.05. In the biochemical tests, the bacterial isolates exhibited specific characteristics of R. solanacearum in two bacterial isolates. In the inhibition tests, treatment four and treatment one (consortium of the three Trichoderma isolates and Trichoderma viride) showed the highest inhibitory potential, with 76.07% and 61.19%, respectively. The consortium of Trichoderma isolates demonstrated the highest inhibitory potential against R. solanacearum, with day 10 being the time with the highest percentage of inhibition (72.61%). Keywords: Bacterial wilt, Ralstonia solanacearum, Trichoderma, inhibition