trichoderma

In this research, the potential of Trichoderma species in biocontrol of root-knot nematode was investigated through the changes of the biochemical compounds involved in induced defense in pistachio seedlings. Trichoderma compounds, including spore suspension and crude extract, were used by soil application and foliar spraying. The results of biochemical tests revealed that the used stimulants caused the accumulation of peroxidase (POX), polyphenol oxidase (PPO), phenylalanine ammonialyase (PAL) and phenolic compounds of the seedlings and as a result increased their resistance against the pathogens. Biological compounds as well as Trichoderma isolates showed better performance than chemical compounds in terms of increasing the enzyme level and its durability. To measure the activity of enzymes and total phenol content, sampling was done on day 1, 4, 8, and 12 post inoculation of the nematode (dpi). The highest increase in POX was observed on the fourth and eighth dpi in the foliar and soil application methods, respectively. The amount of PPO in soil application with spore suspension and the crude extract had a greater increase on the eighth and twelfth dpi. The highest amount of PAL enzyme was observed on the fourth and eighth dpi using crude extract and spore suspension of the mixed strains with micronutrient. In treatment of biological compounds, the total phenolic content increased rapidly on the eighth and twelfth dpi.

In this study, the effect of two fungal species and also a strigolacton phytohormone was evaluated on inducing resistance in two tomato cultivars infected with fusarium wilt disease. In this greenhouse experiment, two cultivars of tomato namely, Captain and 4129 and Trichoderma reesei, Rhizophagus irregularis and GR24 phytohormone (106µM) were used. For this purpose, a factorial experiment was used in a completely randomized design with three replications in different time periods after inoculation of the pathogen (0, 7, 15, 35 days). The effect of biocontrol treatments on changes of some antioxidant enzymes, phenol, total protein and disease severity was assayed. Data analysis showed that the highest activity of all three enzymes with different values for both cultivars occurred during 35 days after inoculation. Among combined and single treatments, application of a combination of three biocontrol factors (T. reesei, R. irregularis and GR24 phytohormone), respectively showed significant effect on increase of measured parameters compared with other treatments. Based on the results of this study it is suggested that application of all three agents in liquid form can be considered as a limiting factor for the growth of the pathogen on the seed surface besides inducing resistance against disease.

In this research, the compatibility of Trichoderma species along with Nanocide and fungicide for the integrated management of this pathogenic fungi Sclerotinia sclerotiorum, has been studied. For this purpose, the effect of three isolates of Trichoderma harzianum, one isolate of T. virens, one isolate of T. atroviride and one isolate of T. koningii on the three isolates of pathogenic agent (SS1, SS2, SS3) in PDA medium containing 5 levels of Nanocide (0,30,60,100,130) by dual culture technique in the laboratory condition were studied. Then the effects of T. harzianum (1211), T koningii (iso2) and T. virens (6011) with two levels of Noniocid (10 & 30 ppm) and Iprodione+carbendazim fungicide (2 & 5 ppm) on one isolate of pathogenic agent in greenhouse condition, were evaluated. The lowest inhibition of mycelia growth of S. sclerotiorum in PDA medium with Nanocide, was 6%, that indicated for treatment S. sclerotiorum (SS2) × T. virens (6011) at level 10 ppm. In greenhouse condition, Trichoderma spp were tested in two stages, seed coated with Trichoderma conidia cell suspension and use Trichoderma mixed with soil. The evaluated parameters were height and wet and dry weight of the plant. The first experiment, was seed coated with Trichoderma conidia cell suspension, the most fresh weight was for T. harzianum (1211) as control and the most height was for T. koningii (iso2) alone. The second experiment, was for Trichoderma mixed with soil showed a significant increase in the most fresh and dry weight were for T. harzianum (1211) + 30 ppm Nanocide treatment and the most height of seedlings was also for T. harzianum (1211) + 2 ppm Iprodione–carbendazim (P≤0.01(. the statistical grouping showed that the treatments in which Trichoderma species were used alone showed no significant difference with treatments with Nanocid and fungicide in the wet and dry weight and height plant. Beside, using Trichoderma alone rather than the combination of Nanocid and fungicide, showed the better effect on growth parameters of the infected canola.

The predator mite, Amblyseius swirskii Athias and Henrioti, is one of the effective and polyphagous biological control agents that feed on different pest species such as thrips, whiteflies, and two spotted spider mites. Currently, it is used to control western flower thrips (WFT), Frankliniella occidentalis (Pergande), and some other insect pests but in times of outbreak and high density of the pest population, its efficiency is reduced and it is necessary to use complementary methods to control the pest damage. In this study, the effect of treated bell peppers (Lorca variety) with Jasmonic acid (0.5 mm), Trichoderma harzianum Rifai T22 (10 ml per plant from 107 spore/ml suspension), and the combination of Jasmonic acid with T. harzianum (JA + Th) was investigated on the biological characteristics and life table parameters of A. swirskii reared on WFT the. The experiment was carried out with 80 replications for each treatment in constant environmental conditions (25 ± 1°C, 65 ± 5% RH, and 16:8 h light: dark). Based on the results, the longest (9.41 days) and shortest (7.94 days) developmental time of immature stages were obtained in JA + Th treatment and control, respectively. The shortest female adult longevity (24.92 days) were also observed in JA + Th treatment. All the life table parameters showed a significant difference. The highest and lowest values of the intrinsic rate of increase (r), net reproductive rate (R0) and, finite rate of increase (λ) were estimated as 0.1688 and 0.1300 day–1, 24.49 and 11.71 (eggs/individual), and 1.184 and 1.139 day–1 for control and JA + Th treatment, respectively. The results of this study could be used in the application of A. swirskii with JA + Th treatment in integrated management programs of WFT..

Sugarcane is an important commercial product for sugar production in the world. A perennial plant from the cereal family, which is susceptible to various pests and diseases due to the long cultivation period, which affects its production. Pokkah boeng disease caused by Fusarium species is one of the important and developing diseases of sugarcane worldwide. In this research, the pathogenicity of Fusarium species related to this disease, F. verticillioides, F. proliferatum, F. sacchari, F. andiyazi, F. acutatum in sugarcane, with two methods of pathogenicity test of cut stems under laboratory conditions and pathogenicity test in Greenhouse conditions were carried out. To calculate the severity of the disease in different species, the length of the wound area on the canes was measured. The results showed that the intensity of pathogenicity in three species F. verticillioides, F. proliferatum and F. sacchari was higher than other species. In another part, the antagonistic property of the endophytic fungus Trichoderma afroharzianum isolated from healthy sugarcane plants was used for biological control of this disease in greenhouse conditions. The effectiveness of the biocontrol agent was determined by measuring the fusarium index, the length of the wound area and plant growth factors, which indirectly contribute to the reduction of disease damage. The results showed that all the treatments applied with endophytic fungi were successful in reducing the disease and increasing the growth factors of the treated plant compared to the control.

The world's population is growing rapidly. To feed this large population, more crops must be produced. The broad use of fertilizers, pesticides and other inputs increases the productivity of existing agricultural lands and the amount of food production, but this increase in yield causes damage to the environment, soil degradation and the destruction of its natural microbial population. To prevent these harmful effects of the chemicals, an eco-friendly approach is needed to ensure human health and the environment. In the innovative view of agricultural production, there is a growing demand for the use of biofertilizers instead of agrochemicals. The use of beneficial microorganisms can be a new strategy to improve plant health and productivity. Natural microbial populations play an important role in the solubilizing and mineralizing of soil nutrients, which is very important for plant growth and development. Among the various microbial populations, fungi known as plants growth promoting fungi (PGPF) have recently received increasing attention. For decades, plant growth promoting fungi such as Trichoderma, Penicillium, Phoma, Aspergillus and Fusarium have been studied. Studies have shown that these fungi, regulate plant growth without environmental pollution and increase plant tolerance to plant pathogens. In this review a brief description of plant growth promoting fungi is given first. In the following, the nature and composition of these fungi as well as the mode of actions, formulation and related challenges will be concidered.

Trichoderma species are the main causes of decomposition and decay of agricultural residues and are considered for the control of plant pathogens, especially fungi and nematodes in the world. Trichoderma species have the ability to produce microbial enzymes such as xylanases, which are used in the paper and food processing industries. These enzymes improve the digestibility of nutrients in certain diets in ruminants and poultry, where there is no digestive enzyme that can digest the complex carbohydrates in the cell wall. These enzymes have the power to digest and hydrolyze these substances. South khorasan province due to hot and dry climate, water shortage and successive droughts, saline water in agriculture, pests and diseases, soil with low fertility for planting irrigated wheat needs cultivars resistant to these stresses. Narin cultivar is the latest cultivar introduced for this province. The characteristic of this cultivar are more compatibility with salinity stress areas and relative maturity with other wheat cultivars.
In order to investigate the effect of simultaneous use of Trichoderma harzianum and plant mulch on yield and physiological characteristics of wheat of Narin cultivar and its effect on the interaction of this cultivar with Alternaria alternata in 2019-2020 in Birjand Faculty of Agriculture Research Farm an experiment asComplete randomization block design was performed with four replications. Treatments included control (without application of Trichoderma), Trichoderma as soil application, Trichoderma as leaf application in granulation stage, Trichoderma application as soil and leaf application in granulation stage. In the granulation stage, each experimental unit was divided into two parts and Alternaria leaf spot pathogen treatment at two levels (inoculation in the granulation stage and without inoculation) was considered as a sub-factor in the experiment. The purpose of using the pathogen treatment was to evaluate the effect of Trichoderma in the presence of the pathogen. This fungus was prepared from the archives of the Plant Pathology Laboratory of Birjand University of Agriculture, which had previously been isolated from the wheat of this province. To inoculate this pathogen, a suspension with a concentration of 106 spores per ml of A. alternata was used from a 7-day fungus colony on PDA medium and its effect on physiological traits (including total phenol, chlorophyll a, chlorophyll b, carotenoids, total chlorophyll) were investigated. To investigate the effect of different applications of Trichoderma on Narin cultivar from another part of the plot without pathogen treatment was analysis of growth traits, yield and yield components including chlorophyll index, including green and dry stem height, spike length, weight, grain yield, biological yield, number and weight of grains per spike, spikes number and weight per unit area were measured.
The aim of using pathogen treatment was to evaluate the biological control of Alternaria wheat leaf spot agent by T. harzianum in different methods by using Trichoderma in the presence of Alternaria in comparison with the absence of Alternaria and its effect on physiological traits (including total phenol, chlorophyll a, Chlorophyll b, carotenoids, total chlorophyll) were evaluated. No symptoms of necrosis or leaf chlorosis were observed after pathogen inoculation. Analysis of physiological traits (total phenol, chlorophyll a, chlorophyll b, carotenoids, total chlorophyll) showed that only the simple effect of inoculation or non-inoculation of Alternaria with Trichoderma significantly different (P <0.05) in terms of total phenol content. Due to the presence of Alternaria as a pathogen, it may lead to a reaction of the plant's defense system, and Trichoderma can also increase phenolic compounds to counteract the pathogen. Analysis of growth traits, yield and yield components showed that Trichoderma treatment had no significant effect on any of them.
This study, for the first time showed that A. alternata can cause disease on wheat Narin cultivar. Also, this research studied the effect of T. harzianum on physiological and functional characteristics of wheat Narin cultivar and results demonstrated that T. harzianum can have little effect on these characteristics of Narin cultivar. Concomitant use of Trichoderma in soil and leaves had a greater effect than separate application in roots or leaves. Also, according to other research, the effect of trichoderma varies depending on the environmental conditions including temperature and humidity, soil texture and structure and the type of wheat cultivar.

The greenhouse whiteflies, Trialeurodes vaporariorum (Westwood), are one of the major pests of vegetable and ornamental crops in greenhouses in the world. They damage crops through direct feeding, inserting their stylet into leaf veins, and extracting nourishment from the phloem sap. As a by-product of feeding, honeydew is excreted, which is an indirect but yet another substantial source of damage. The third most harmful characteristic is the ability of adults to transmit various plant viruses. Induced resistance is a non-chemical control method that has no negative impact on the environment and human health and can be a desirable approach in plant protection and pest control. Trichoderma spp. has spread in many ecosystems and its various species such as Trichoderma harzianum Rifai have been successful as non-pathogenic symbionts in controlling plant pathogens via different mechanisms. Some of these mechanisms include enzymatic degradation, secretion of antibiotics, and increasing root absorption capacity. Recent findings suggest that T. harzianum is also a potent inducer of Induced Systemic Resistance (ISR) and can stimulate the immune system in plants against plant diseases and pests. In this study, the efficacy of T. harzianum Tr6 was investigated on host preference and egg production of T. vaporariorum.

To evaluate the effect of T. harzianum Tr6, four tests were carried out: 1) Total phenol assay using Folin–Ciocalteu reagent, 2) The effect of time on induced resistance, 3) Free choice, and 4) Non choice. These tests were conducted on tomato plants (Falat cultivar) at 25±2°C, relative humidity of 60-70%, and a photoperiod of 8 h/16 h (day/night). Also, these experiments were performed on one-day-old adults in plots with four or six leaves in shelves equipped with organza mesh.

According to the phenol assay, the highest amount of total plant phenol was observed three and four days after inoculation by Tr6 strain respectively 0.3503±0.001 and 0.3323±0.001mg/g. Therefore, for the next three tests, plants that were inoculated after three days were used as treated samples, and plants watered with distilled water were used as control ones. In these experiments, the lowest number of adults on the back of the leaves after 24 hours was observed two and four days upon inoculation respectively 2.2±  0.86 and 2.0±  0.63. On the other hand, plants inoculated by Tr6 displayed a significant decrease in adults on the back of the leaves (3.4± 0.66), egg-laying (7.4± 1.51), and honeydew droplets (1± 0.28) compared to control plants.

The most important factor in controlling the whitefly population is reducing the reproduction rate. Induced resistance can repel insects from plants and limit their nutrition, and thus, reduce their reproduction. This study implied that the inoculation of tomato by T. harzianum Tr6 strain could induce resistance to whitefly and reduce host preference and egg production, as well as honeydew secretion. Therefore, this strain can be a promising option in preventing the outbreak of this multi-generational pest.

Take-all disease of wheat caused by Gaeumannomyces graminis var. tritici is one of the important diseases of wheat worldwide. In this study, application of two Trichoderma species on the control of this disease was evaluated under laboratory and greenhouse conditions. The causal agent of disease was isolated from suspected diseased plants in wheat fields of Khorrramabad district, identified according to scientific mycological literatures and its pathogenicity was proven in greenhouse. The mycelial inhibition potential of Trichoderma harzianum and T.viride in dual culture and volatile metabolite effects against the pathogen were tested in vitro. Then, single and combined greenhouse application of the two Trichoderma isolates and triadimenole fungicide for control of take-all disease were investigated using a completely randomized design with 16 treatments and four replications and disease severity and growth indices were recorded and analyzed statistically. In vitro experiments showed that both of the Trichoderma species disintegrated the hypha and inhibited the mycelia growth of G. graminis. Combined application of triadimenole fungicide with the two antagonists, triadimenole, and single application of T. harzianum and T. viride reduced take-all severity by 70.6, 58, 47.06 and 47.06 percent, respectively in greenhouse after 30 days of sowing. Trichoderma biocontrol agent and integration of chemical compounds with antagonists would provide promising strategy for management of wheat talke-all disease.

Pistachio is one of the most important export products of the country and root knot nematode is one of the threatening factors in its production. The most prevalent species in pistachio orchards are those of Meloidogyne javanica and M. incognita. Plants have a wide range of defense mechanisms effective against the invasion of various pathogens and pests. These mechanisms include pre-existing physical barriers, chemical barriers, and induced defense responses. Beneficial soil microorganisms such as Trichoderma spp. and arbuscular mycorrhizal fungi (AMF) can protect plants from infection by direct mechanisms such as production of toxins, enzymes, and other metabolites or by inducing systemic resistance. Induce resistance to the root knot nematode occurs following an increased accumulation of different antagonistic compounds such as peroxidase and polyphenol oxidase. Increased levels of these enzymes has been observed in different plants that are responsible for the induced protection against Meloidogyne.

In this study potential of antagonistic fungi, vesicular-arbuscular mycorrhiza (Funneliformis mosseae, Rhizophagus intraradices, Funneliformis caledonius) and Trichoderma (Tricoderma aureoviride,Tricoderma harzianum) and mixed of both fungi against Meloidogyne javanica under greenhouse conditions was investigated. In order to investigate the effect of antagonistic fungi on the induction of defense enzymes in pistachio seedlings of Badami Riz Zarand cultivar, the study was performed as a factorial experiment based on completely randomized design with twelve treatments in three replications in the greenhouse. Pistachio seedlings were inoculated at the stage of 8-10 leaf with 60 g of mycorrhizal mixture and three months later, these plants were sampled for examination. In order to ensure the purity of the fungi and the colonization of the roots, staining of the plant roots was performed and microscopic examination was performed to observe different organs of the fungus. After confirming the mycorrhiza treatment, Trichoderma treatment was applied. For Trichoderma treatment, 10 g of mixture of isolates T1, T2, T3, T4 and T5 per kg of soil was used. Pure nematode populations were prepared from a single egg mass on Early Urbana tomatoes. Pistachioseedlings were inoculated with 5000 second-stage juveniles of nematode 21 days after Trichoderma treatment.Nematode indices including the number of galls, egg masses and second juveniles per gram of root, the number of eggs in each egg mass and reproductive factor after 75 days for each treatment were measured.The second experiment was performed to investigate the effect of biological treatments on nematode indices in a completely randomized design with six treatments and three replications. Defense enzymes level of Peroxidase (POX), Polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) determined at four times of one and a half, three, five and a half and twelve days after nematode inoculation.

Disease indices showed a significant decrease in fungi treatments compared to the nematode control. Trichoderma treatment showed a significant difference in all indicators compared to the other treatments. Reproductive index in Trichoderma treatment and its combination with mycorrhizal treatment decreased by 72 and 33.3 and nematode population decreased by 73.4% and 36.2% compared to the control, respectively. Extracellular hydrolytic enzymes play important role in the infection process of Tichoderma species against plant-parasitic nematodes. In mycorrhiza treatment, although there was no significant difference in gall index and egg mass with the control, but the number of second juveniles and nematode reproductive factor showed a significant decrease compared to the control. This may be due to the small size of the egg mass and the effect on the number of eggs. Previous results on mycorrhizal species of Rizophagus irregularis in tomato plant showed that egg masses and number of eggs in treated roots have a significant reduction. The maximum enzymatic activity for POX, and PPO was obtained in different treatments on the twelfth day. The maximum amount for PAL activity in seedlings treated with mycorrhizal and Tricoderma fungi was observed after five and a half days. The level of different enzymes increases after treatment with mycorrhiza and Trichoderma in plants, each of which plays a role in limiting the development of nematodes.

Due to the high proliferation of nematodes in pistachio orchards and due to the environmental hazards of nematicides, the use of biocontrol agents is recommended. The studied fungal strains in the present study could be used as components in an integrated approach to manage M. incognita on pistachio plants. The use of plant growth promoting fungi such as mycorrhiza and Trichoderma while improving plant growth, can reduce the use of fertilizers and chemical pesticides and are effective for better plant growth and development and disease control. However, further studies on the use of combinations of these fungi with other bacterial antagonists and even animal manures as well as garden studies are necessary.

Blast is one of the most important and destructive rice diseases in the world. Nanoparticles are antimicrobial agents used as biological and non–biological stimulants and can induce resistance in plant against pathogens. Effects of different biological and non–biological nanoparticles on inhibition of various plant fungal pathogens has been proved. However, no study has been done about the effect of biological nanoparticles on control of this disease through induction of resistance and expression of defense genes. In this study, in addition to direct effect of biological silver nanoparticles synthesized using Trichoderma harzianum fungus in vitro, its indirect effect was investigated by inducing systemic resistance in susceptible local Tarom cultivar on pathogenic fungus Magnaporthe oryzae under greenhouse conditions. For this purpose, expression of several important defense genes investigated in biological silver nanoparticle–treated plants in comparison with control plant (without biological silver nanoparticle) using real–time qPCR technique at different times after pathogen inoculation. The results showed a positive effect of different concentrations of biological nanoparticles in reduction of pathogen growth in comparison with the control treatment so that the amount of inhibition of pathogen growth in different concentrations (36, 27, 18, 9, 4.5 ppm) was 92, 81, 56, 28 and 7 percent compared to the control treatment, respectively. Phenotypic study of rice plant interaction with the fungus causing blast disease in presence of biological nanoparticle showed that there was no significant difference between the disease severities in biological nanoparticle–treated plants compared to control plants. Also, accumulation of transcripts of NPR1, PR2, PR3 and LOX genes between two mentioned treatments did not show significant increase. Therefore, indirect effect of biological silver nanoparticle on pathogenic fungus by induced resistance and increasing the rice plant defense genes is not considerable.