Revolutionary Role of Trichoderma in Sustainable Plant Health Management: A Review

The use of chemical pesticides in agricultural practices has led to significant concerns related to health and the environment in the last few decades. Consequently, there has been a growing interest in finding alternative approaches for controlling pests and diseases that are effective and environmentally friendly. Among these alternatives, Trichoderma harzianum has gained attention due to its remarkable ability to combat various crop pathogens in sustainable form. Biocontrol agents have gained prominence as eco-friendly substitutes for conventional chemical pesticides in disease management and crop improvement. T. harzianum, a common filamentous fungus, has emerged as a promising biocontrol agent due to its multifaceted strategies for suppressing diseases and promoting crop growth. T. harzianum fosters plant growth by aiding nutrient absorption, improving soil structure, and generating growth-promoting substances like auxins and cytokinins. Field studies have substantiated the efficacy of T. harzianum in managing a wide array of plant diseases caused by fungi, bacteria, and nematodes whether used as a seed treatment, soil application, or foliar spray, T. harzianum establishes a beneficial presence early in the plant's life cycle, providing enduring protection. In conclusion, T. harzianum holds immense potential as a biocontrol agent to sustainably safeguard crops. Trichoderma species play a pivotal role in managing plant diseases due to their versatile mechanisms. As global agriculture seeks alternatives to chemical pesticides, leveraging T. harzianum 's potential offers a valuable avenue toward resilient and environmentally safe crop production.

FOLIAR ENDOPHYTE FUNGI AS CANDIDATE FOR BIOCONTROL AGAINST Moniliophthora spp. OF Theobroma cacao (Malvaceae) IN ECUADOR / Hongos endófitos foliares como candidatos a biocontroladores contra Moniliophthora spp. de Theobroma cacao (Malvaceae) en Ecuador

ABSTRACT The adaptability of endophytic fungi to their hosts, the ecological benefits that it provides and the various antagonistic mechanisms against pests make them an alternative for the biological control of diseases. The potential of 17 strains of foliar endophytic fungi (FEF) obtained from healthy Theobroma cacao tissue as candidates for the biological control of Moniliophthora roreri (MR) and M. perniciosa (MP) was determined. We evaluated: i) mycoparasitism of FEF against colonies of Moniliophthora spp., ii) the effects of crude metabolites of FEF on the pathogens' growth, and iii) the ability to recolonize healthy leaves of the host by leaf assays. Three strains of Lasiodiplodia theobromae were the most promising: Ec098, Ec151 and Ec157. These strains inhibited the growth of MR and MP, both in the confrontation of the colonies and by their metabolites and, additionally, recolonized the host between 80-100 % of the time. Other strains showed outstanding values i n one indicator, and not desirable in others. For example, Ec035 (L. theobromae) showed the highest levels of mycoparasitism against both pathogens in the interaction of the colonies, and the second best for its metabolites, but could not reinfect the host. Strain Ec059 (Xylaria feejeensis) reinfected 100 %, but did not show desirable attributes of antagonism. On the other hand, the metabolites of Ec107 (Colletotrichum gloeosporioides s.l.) inhibited MR by 60 %, but also stimulated the growth of MP. No strain achieved all desirable characteristics for a biological control agent.

RESUMEN La adaptabilidad de los hongos endófitos a sus hospedantes, los beneficios ecológicos que le brinda y los diversos mecanismos antagónicos contra plagas que poseen los convierten en una alternativa para el control biológico de enfermedades. Se determinó el potencial de 17 cepas de hongos endofíticos foliares (FEF) obtenidas de tejido sano de Theobroma cacao como candidatas para el control biológico de Moniliophthora roreri (MR) y M. perniciosa (MP). Se evaluaron: i) el micoparasitismo de los FEF frente a colonias de Moniliophthora spp., ii) la acción de los metabolitos crudos de los FEF en el crecimiento, y iii) la habilidad para recolonizar hojas sanas del hospedante mediante ensayos de hojas sueltas. Tres cepas de Lasiodiplodia theobromae fueron las más promisorias: Ec098, Ec151 and Ec157. Estas cepas inhibieron el crecimiento de MR y MP, tanto en el enfrentamiento de las colonias como mediante sus metabolitos y, adicionalmente, recolonizaron el hospedante entre el 80-100 % de las veces. Otras cepas mostraron valores destacados en un indicador, y no deseables en otros. Por ejemplo, la Ec035 (L. theobromae) mostró los niveles más altos de micoparasitismo contra ambos patógenos en la interacción de las colonias, y el segundo mejor por sus metabolitos, pero no pudo reinfectar el hospedante. La cepa Ec059 (Xylaria feejeensis) reinfectó 100 %, pero no mostró los atributos deseados de antagonismo. Por su parte, los metabolitos de Ec107 (Colletotrichum gloeosporioides s.l.) inhibieron a MR en un 60 %, pero también estimularon el crecimiento de MP. Ninguna cepa logró todas las características deseables para un agente de control biológico.

Scytalidium parasiticum sp. nov., a New Species Parasitizing on Ganoderma boninense Isolated from Oil Palm in Peninsular Malaysia

A mycoparasite, Scytalidium parasiticum sp. nov., isolated from the basidiomata of Ganoderma boninense causing basal stem rot of oil palm in Johor, Malaysia, is described and illustrated. It is distinct from other Scytalidium species in having smaller asci and ascospores (teleomorphic stage), longer arthroconidia (anamorphic stage), hyaline to yellowish chlamydospores, and producing a fluorescent pigment. The phylogenetic position of S. parasiticum was determined by sequence analyses of the internal transcribed spacers and the small-subunit ribosomal RNA gene regions. A key to identify Scytalidium species with teleomorphic stage is provided.

Mycoparasitism of Trichoderma Spp. on Rhizoctonia Bataticola, the Causal Agent of Dry Root Rot of Chickpea.

Mode of parasitism between Trichoderma and Rhizoctonia bataticola was examined under a microscope. Formation of several loops and coiling around the hyphae of pathogen, forming a thick compact rope like structure followed by rupturing, twisting and leakage of hyphal protoplasm, air bubbling inside the cytoplasm, breaking of cytoplasmic continuity, aggregation of cytoplasm within cell leading to severe vacoulation were observed at later phase of interaction.

Caracterización de enzimas hidrolíticas de Aspergillus ficuum producidas en fermentación sólida sobre torta de canola / Characterization of Aspergillus ficuum hydrolytic enzymes produced in solid state fermentation of cold-pressed canola cake

En el presente trabajo, se describe la caracterización respecto al pH y temperatura de extractos semipurificados mediante ultrafiltración escalonada de las enzimas fitasa, celulasa y xilanasa de Aspergillus ficuum cepa DSM 932 producidos en fermentación en estado sólido (en adelante SSF) y usando torta de canola como sustrato. La fitasa presentó un pH y una temperatura óptima de 5.0 y 60ºC respectivamente, en tanto que la celulasa presentó un pH óptimo de 7.0 con una temperatura óptima de 60°C y el extracto de xilanasa un pH óptimo de 5.4 y una temperatura óptima de 45°C.(

This paper, describes the characterization respect to pH and temperature of semi-purified extracts by ultrafiltration step of the enzymes phytase, cellulase and xylanase produced by Aspergillus ficuum DSM 932 strain, in solid state fermentation (SSF) using cold-pressed canola cake as substrate. Phytase showed the optimal pH and temperature 6.0 and 60°C, respectively, while cellulase showed a pH optimal of 7.0 with an optimal temperature of 60°C and xylanase extract an optimal pH of 5.4 and an optimal temperature of 45°C.

Study of the interactions between Penicillium oxalicum Currie & Thom and Alternaria alternata (Fr. ) Keissler

The aim of this research was the analysis of the possible antagonistic effect of Penicillium oxalicum over the pathogen rice fungus A. alternata under different conditions of temperature, water activity and culture media. The macroscopic study of the dual growth revealed that according to the Index of Dominance P. oxalicum was more competitive that A. alternata at 25ºC whereas at 15ºC was this species. Microscopic analysis showed that P. oxalicum was a mycoparasite of A. alternata at all conditions tested. The antagonist penetrated into A. alternata and disintegrated its conidiophores and conidia. The results suggests that P. oxalicum may be a possible biological control agent of the rice pathogens in a future.

Stem Blight Control of Schizonepeta tenuifolia Caused by Phytophthora nicotianae Using Trichoderma spp / 中草药·英文版

Objective To control stem blight disease of Schizonepeta tenuifolia caused by Phytophthora nicotianae.Methods The antagonist effect of 13 Trichoderma strains(including T.viride and T.hamianum)was evaluated upon mycelia growth of P.nicotianae.Trichoderma strains with high antagonistic activities against the pathogen were used to control stem blight of S.tenuifolia in the field.Results Of 13 Trichoderma strains tested,T.viride strain M3 showed maximum mycelia growth inhibition(83.2%)to the pathogen,followed by T.viride strain Tv04-2(78.2%)and then T.harziamum strain ThB(65.0%),in vitro.Fungal cell wall degrading enzymes,protease,and β-1,3-glueanase were analyzed qualitatively and quantitatively in further study.T.viride strains M3,Tv04-2,and T.harzianum strain ThB efficiently against P.nicotianae were used to control stem blight of S.tenuifolia in the field,and T.viride strain M3 showed the best biocontrol potential.Conclusion Trichoderma spp.can be used as alternatives of pesticides to control stem blight,one of the serious soilhome diseases of S.tenuifolia caused by P.nicotianae.However,though T.viride strains Tv04-2 aad T.harzianum strain ThB are also highly against P.nicotianae in vitro,the controlling efficacy of them on stem blight disease is not as excellent as T.viride strains M3 in the field.

Micoparasitismo biotrofico de Fusarium oxysporum sobre Cunnighamella sp / Biotrophic mycoparasitism of Fusarium oxysporum on Cunnighamella sp

Se describe un caso de micoparasitismo biotrófico de ocurrencia natural en el suelo, entre las hifas de una cepa de Fusarium oxysporum complex y Cunninghamella sp. Las hifas de F. oxysporum se desarrollaron sobre las células vivas del hospedador, mostrando 2 tipos de efectos parasíticos: uno de enrollamiento y otro de contacto con penetración de las hifas, sin la aparente eliminación del hospedador. Esta situación poco común en la literatura, demuestra las capacidades adaptativas de esta especie al micoparasitismo en grupos filogenéticamente distantes.

This paper describes a case of mycoparasitism naturally occurring, where Fusarium oxysporum parasitizes hyphae of Cunninghamella sp, to show mycoparasitism between the two fungi. This is a case of biotrophic mycoparasitism by contact. The hyphae of F. oxysporum developed closely along the living cells of the host showing mycoparasitic effect, some for a loop, and other contact with penetration of the hyphae. This situation is rare in the literature, demonstrates the adaptive capacities of this species to mycoparasitism in phylogenetically distant groups.

Efecto antagónico de Trichoderma harzianum sobre algunos hongos patógenos postcosecha de la fresa (Fragaria spp) / Antagonist effect of Trichoderma harzianum over some strawberry (Fragaria spp) post harvesting fungi pathogens

La podredumbre blanda (Rhyzopus stolonifer), la podredumbre negra (Mucor spp., Aspergillus niger y Pythium spp.) son las enfermedades postcosecha más comunes de la fresa (Fragaria spp.) y generan grandes pérdidas de estas. Durante muchos años se han utilizado fungicidas sintéticos para controlar a estos patógenos, pero se ha demostrado que se hacen resistentes a dichos productos, además de representar un riesgo potencial al ambiente y la salud humana. Todo esto ha conllevado a la búsqueda de alternativas naturales como el empleo de extractos vegetales y antagonistas microbianos, siendo Trichoderma harzianum el antagonista mas utilizado como control biológico. El objetivo de este estudio fue determinar el efecto antagónico de T. harzianum sobre algunos hongos patógenos postcosecha en fresa y conocer su mecanismo de acción. Las muestras de fresa fueron transportadas al laboratorio en los mismos empaques de venta, y posteriormente las fresas fueron colocadas en cámaras de germinación controlando la humedad para el desarrollo rápido de hongos presentes en la fruta. Se identificaron los hongos Rhyzopus stolonifer, Mucor spp., Penicillium digitatum, Rhizoctonia solani, Aspergillus niger y Pythium spp., sobre los cuales se realizó la prueba de antagonismo usando al hongo T. harzianum. La velocidad de crecimiento del biocontrolador fue mayor que el crecimiento de los hongos postcosecha (p<0,01) y a las 96 horas de incubación la caja de Petri estaba completamente cubierta y en la zona de encuentro entre éstos se observó que el mecanismo de acción del biocontrolador fue de tipo micoparasítico. T. harzianum resultó ser un excelente controlador in vitro de hongos postcosecha de frutos de fresa.

Soft rotting (Rhyzopus stolonifer) and black rotting (Mucor spp., Aspergillus niger and Pythium spp.) are the most common post harvesting strawberry (Fragaria spp.) diseases, generating great losses. During many years synthetic fungicides have been used to control these pathogens, but their development of resistance to these products has been demonstrated, following to the fact that they represent a potential environmental and human health risk. This has lead to the search of natural alternatives such as the use of vegetal extracts and microbial antagonists, being Trichoderma harzianum the antagonist most widely used as biological control. The purpose of this study was to determine the antagonist effect of T. harzianum over some post strawberry harvesting pathogens and determine their mechanism of action. The strawberry samples were transported to the laboratory in the same packages in which they were sold, and then were placed in germination chambers, controlling humidity to obtain a rapid development of the fungi present in the fruit. We identified the following fungi:  Rhyzopus stolonifer, Mucor spp., Penicillium digitatum, Rhizoctonia solani, Aspergillus niger and Phytium spp., which were tested for antagonism, using the T. harzianum. The growth speed of the biocontroller was greater than that of the post harvest fungi (p<0,01) and at 96 hours of incubation the Petri dish was completely covered, and the encounter area between them showed that the action mechanism of the biocontroller was of the mycoparasitic type. T. harzianum turned out to be an excellent in vitro controller of post strawberry harvest fungi.

Lasiodiplodia theobromae is a Mycoparasite of a Powdery Mildew Pathogen

Powdery mildews on over 40 plants in Bangalore were screened during July-December of 2003~2008. Isolates from mycoparasitised Oidium caesalpiniacearum of Bauhinia purpurea comprised Lasiodiplodia theobromae, in addition to Ampelomyces quisqualis. Koch's postulates were satisfied to establish the mycoparasitism of L. theobromae. This is the first report that L. theobromae acts as a mycoparasite of a powdery mildew.