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Maize is one of the major crops in the world and the most productive member of the Gramineae family. Since cold stress affects the germination, growth, and productivity of corn seeds, the present study aimed to investigate the effect of seed biopriming with Trichoderma harzianum on the tolerance of two genotypes of maize seedlings to cold stress. This study was conducted in triplicates in factorial experiment with a complete randomized block design (CRBD). The study was conducted in the greenhouse and laboratory of the University of Mohaghegh Ardabili, Ardabil, Iran. Experimental factors include two cultivars (AR68 cold-resistant and KSC703 cold-sensitive maize cultivars), four pretreatment levels (control, biopriming with T. harzianum, exogenous T. harzianum, and hydropriming), and two levels of cold stress (control and cold at 5 °C) in a hydroponic culture medium. The present study showed that maize leaves' establishment rate and maximum fluorescence (Fm) are affected by triple effects (C*, P*, S). The highest establishment (99.66%) and Fm (994 units) rates were observed in the KP3 control treatment. Moreover, among the pretreatments, the highest (0.476 days) and the lowest (0.182 days) establishment rates were related to P0 and P3 treatments, respectively. Cultivar A showed higher chlorophyll a and b, carotenoid content, and establishment rate compared to cultivar K in both optimal and cold conditions. The highest root dry weight (11.84 units) was obtained in cultivar A with P3 pretreatment. The pretreatments with T. harzianum increased physiological parameters and seedling emergence of maize under cold and optimal stress conditions. Pretreatment and cultivar improved catalase activity in roots and leaves. Higher leaf and root catalase activity was observed in the roots and leaves of cultivar K compared to cultivar A. The cold treatment significantly differed in peroxidase activity from the control treatment. Cultivar K showed higher catalase activity than cultivar A. The main effects of pretreatment and cold on polyphenol oxidase activity and proline content showed the highest polyphenol oxidase activity and proline content in hydropriming (H) treatment. Cold treatment also showed higher polyphenol oxidase activity and proline content than cold-free conditions. [ABSTRACT FROM AUTHOR]

Adaptations of green technologies to counter abiotic stress, including salinity for crops like wheat by using halotolerant microbes, is a promising approach. The current study investigated 17 salt-affected agroecological zones from the Punjab and Sindh provinces of Pakistan to explore the potential of indigenous microbial flora, with their multiple biochemical characteristics in addition to plant growth promoting (PGP) traits, for enhanced wheat production in saline areas. Initially, 297 isolated pure bacterial colonies were screened for salt tolerance, biochemical, and PGP traits. Three bacterial strains belonging to Pantoea spp. and Erwinia rhaphontici with possession of multiple characteristics were selected for the development of the halotolerant bacterial consortium. Inoculation of two local wheat varieties, Faisalabad 2008 and Galaxy 2013, with the consortium for in vitro seed germination assay and sand microcosm experiments exhibited significant improvement of selected plant growth parameters like germination percentage and root structure. Two previously reported PGP fungal strains of Trichoderma harzianum and T. viridae were also used as fungal consortium separately for pot experiments and field trials. The pot experiments exhibited a positive correlation of consortia with metabolic viz. catalase, peroxidase, and proline and agronomical parameters including shoot length, dry weight, number of spikes, spike length, and 100 grain weight. To evaluate their performance under natural environmental conditions, field trials were conducted at three salt-affected sites. Agronomical attributes including days of flowering and maturity, flag leaf weight, length and width, shoot length, number of spikes, spike length, spike weight, number of seeds spike-1, 1,000 grain weight, and plot yield indicated the efficiency of these microbes to enhance wheat growth. Concisely, the bacterial consortium showed better performance and Faisalabad 2008 was a more resistant variety as compared to Galaxy 2013. Initial promising results indicate that further extensive research on indigenous microbes might lead to the development of Pakistan's first salinespecific biofertilizers and sustainable eco-friendly agriculture practices. [ABSTRACT FROM AUTHOR]

Multiphase fermentations are still poorly understood since much of the available information focused on global rather than local data and the most used parameter to control the dispersion of gas in the stirred tank is the agitation rate. However, the energy dissipated in the stirred tank is influenced by the properties of the broths, such as viscosity. Therefore, the objective of this work was to use a retrofitted power input strategy in order to maintain constant the total power input per unit volume (P g /V), studying the local gas hold-up (φ) and interfacial area (a) values in three regions in a pilot-scale stirred tank at different values of Trichoderma harzianum mycelial biomass concentration, airflow rate and constant P g /V. We found that the constant P g /V regime was an effective strategy that allows to discern the effects of different parameters in the local values of gas hold-up and interfacial area. Under constant retrofitted total gassed power input, the biomass concentration showed no influence on the local values of interfacial area and gas hold-up. Depending on the position of the probe, φ and a varied up to 60.6% and 63.8%, respectively. The highest P g /V and airflow rate conditions determined the highest values in φ and a , but not in the same proportion in the three zones tested. [Display omitted] • Local φ and a were analyzed under a constant P g /V regime with a mycelial broth model. • If P g /V is kept constant, biomass concentration had no effect on gas hold-up (φ). • Depending on the port analyzed, mass transfer area (a) varied up to 63.8%. [ABSTRACT FROM AUTHOR]

Rice blast and BLB diseases caused by Pyricularia oryzae and Xanthomonas oryzae respectively has a significant impact on rice yield and quality worldwide. Biological disease control has been shown to be one of the most effective ways to manage rice diseases. The present study was conducted at Rice Research program, CSI, NARC, Islamabad to evaluate the in vitro and in vivo management of BLB and rice blast diseases by Trichoderma harzianum. T. harzianum inhibits almost 58% mycelial growth of the P. oryzae and 50% colony growth of X. oryzae. Effect of T. harzianum on seed germination was observed on agar media at three different concentrations (106, 108, and 1010). T. harzianum at concentration of 1010 showed enhancement of plant growth; the maximum root length augmented from 38 to 47% and the shoot length was 15 % in KSK-434 and 44% in other three varieties as compared with control. Plant growth were examined under the impact of Volatile Organic compounds of T. harzianum. Root and shoot length were increased 24 to 48% and 15 to 39%, respectively compared with control. In the in vivo management, T. harzianum applied on the rice plants sown in pots. The disease pathogens Xanthomonas oryzae and Pyricularia oryzae were inoculated in rice plants, T. harzianum controlled the diseases at two concentrations i.e., 108 and 1010. The disease was controlled 70 to 77% as compared to control. It was concluded that the characters as plant height, panicle length, number of tillers, and number of grains per panicle and yield of rice also increased with the application of T. harzianum. T. harzianum may serve an efficient biological agent in rice crop to mitigate the diseases stress. [ABSTRACT FROM AUTHOR]

Fungal pathogens cause economically important diseases in tomato. Fungus Curvularia lunata has been reported the cause of tomato leaf blight and fruit rot. The objective of this study was in vitro evaluation of fungicides and biocontrol agents against leaf blight and fruit rot pathogen. For this purpose, surveys of different tomato fields were conducted for the collection of samples from infected tomato fields. For the isolation of C. lunata, potato dextrose agar (PDA) media was used. Pathogen was identified on genus level on the basis of macroscopic and microscopic characteristics. In vitro pathogenicity assays were conducted to check the virulence of isolates. Poison food technique was used for the evaluation of five different fungicides against C. lunata. All fungicides significantly inhibited mycelial growth of C. lunata at 3rd, 5th and 7th day at different concentrations. Nativo showed best results against C. lunata and inhibited mycelial growth to 50.64%, 55.65% and 58.9% followed by Metalaxyl+Mancozeb 37.33%, 43.57% and 45.98% at 3rd, 5th and 7th day, at 50, 100 and 150 ppm concentrations, respectively. Minimum percent inhibition was given by Topsin-M 33.43%, 36.15% and 43.9% at same concentrations. Dual culture technique was used for the evaluation of biocontrol agents (BCAs) against C. lunata. Trichoderma harzianum showed maximum antagonistic potential to suppress the growth of pathogen C. lunata (70.72%). All tested BCAs inhibited the growth of pathogen more than 60% in dual culture assays. The present study revealed that Nativo fungicide and BCA T. harzianum have the potential to control C. lunata. [ABSTRACT FROM AUTHOR]

• Plasmodiophora brassicae Wor., is an obligate biotrophic protest. • P. brassicae infects the roots of cruciferous crops, inducing galls or clubs that lead to wilting, loss of productivity, and ultimately plant death. • The pathogenic effect of clubroot disease is controlled by single and combined exogenous application of melatonin and trichoderma. • The combined inoculation enhanced plant vegetative growth and antioxidant enzyme activities in the infected roots of pak choi plant. Clubroot disease causes significant damage to cruciferous crops worldwide, resulting in severe decrease in plant yield. Plants tolerate biotic stresses through various mechanisms, including pathogen-associated molecular patterns (PAMPs) that activate immunity and plant resistance proteins. However, humans often resort to non-ecofriendly methods such as chemical applications to control biotic stresses. Melatonin (N-acetyl-5-methoxytryptamine) and Trichoderma are environmentally friendly and cost-effective alternative strategies to protect plants from pathogen attacks. Additionally, they have favorable effects on horticultural crop growth, fruit ripening, flowering, and provide stress resistance to abiotic and biotic diseases. In the present study, we aimed to control clubroot disease in Pak choi through single and combined exogenous application of melatonin and Trichoderma. We analyzed their effects on plant biomass, chlorophyll contents and observed alterations in their antioxidant system. Our results demonstrated that the combined application of 50 µM melatonin and 100 g Trichoderma efficiently control clubroot disease up to 74.85% compared to plants only supplemented with Plasmodiophora brassicae , as indicated by the disease index. Furthermore, we observed increased plant growth and antioxidant enzyme activities, including Ascorbic acid peroxidase (APX), superoxide dismutase (SOD); catalase (CAT), glutathione reductase (GR), and peroxidase (POD). Additionally, malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2) levels were reduced. Moreover, increased levels of chlorophyll, carotenoids and plant biomass have been observed in plants co-inoculated with melatonin and Trichoderma application. These findings provide valuable insights that can be utilized to enhance crop stress tolerance in challenging environments and increase plant yield. The use of environmentally friendly and cost-effective alternatives to chemical control can help mitigate the damage caused by clubroot disease to cruciferous crops. [ABSTRACT FROM AUTHOR]

Plant growth promoting fungi (PGPF) were employed in the present study to biocontrol Fusarium wilt disease in pepper plants. Two of the five fungal isolates were chosen based on biochemical characteristics such as their production of hydrocyanic acid, siderophores, and IAA, phosphate solubilization, and in vitro antifungal activities. The most potent fungal isolates were identified as Penicillium expansum (P. expansum) and Trichoderma harzianum (T. harzianum). Using GC-MS, it was found that PGPF extracts contain compounds with antifungal activity, antioxidants, and plant growth stimulators. The combined effect of T. harzianum and P. expansum increased the protection against fusarial wilt by (76.74%), followed by T. harzianum by (50%), then P. expansum by (17.64%). Significant improvement because of using the mixture (T. harzianum and P. expansum) showed an increase in shoot length (59.4%), root length (129%), and number of leaves (52.6%). Chlorophyll A and B levels in infected plants were consistently raised by 28.71% and 67.58%, respectively; as a result of application the mixture (T. harzianum and P. expansum). Also, there was an increase in soluble proteins and carbohydrates in infected plants treated with (T. harzianum) by 25.42% and 31.78% over untreated infected plants, respectively. It could be recommended that the use of targeted PGPF strains, especially a mixture of T. harzianum and P. expansum could be commercially used as therapeutic nutrients against Fusarium wilt of pepper plants. [ABSTRACT FROM AUTHOR]

In this study, we investigated in vitro the potential of Trichoderma harzianum to produce bioactive secondary metabolites that can be used as alternatives to synthetic compounds. The study focused on analyzing two extracts of T. harzianum using ethyl acetate and n-butanol solvents with different polarities. The extracts were examined using phytochemical analysis to determine the content of polyphenols, flavonoids, tannins, and alkaloids. Thin-layer chromatography (TLC) and Gas chromatography-mass spectroscopy (GC-MS) analysis were used to profile volatile organic metabolites (VOCs) present in the extracts. Furthermore, the extracts were tested for their antifungal ability using the poison food technique. For measuring antioxidant activity, the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) test was used. Trichoderma harzianum was shown to have a significantly high content of tannins and alkaloids, with a noticeable difference between the two extracts. GC-MS analysis identified 33 potential compounds with numerous benefits that could be used in agriculture and the medicinal industry. Moreover, strong antifungal activity was identified against Sclerotinia sclerotiorum by 94.44%, Alternaria sp. by 77.04%, and Fusarium solani by 51.48; similarly, the IC50 of antioxidant activity was estimated for ethyl acetate extract by 71.47% and n-butanol extract by 56.01%. This leads to the conclusion that Trichoderma harzianum VOCs play a significant role as an antifungal and antioxidant agent when taking into account the advantageous bioactive chemicals noted in the extracts. However, to our knowledge, this is the first study in Algeria presenting detailed phytochemical analysis and GC-MS profiling of Trichoderma harzianum for two extracts, ethyl acetate and n-butanol. [ABSTRACT FROM AUTHOR]

Priming plants with beneficial microbes can establish rapid and robust resistance against numerous pathogens. Here, compelling evidence is provided that the treatment of rapeseed plants with Trichoderma harzianum OMG16 and Bacillus velezensis FZB42 induces defence activation against Verticillium longisporum infection. The relative expressions of the JA biosynthesis genes LOX2 and OPR3, the ET biosynthesis genes ACS2 and ACO4 and the SA biosynthesis and signalling genes ICS1 and PR1 were analysed separately in leaf, stem and root tissues using qRT-PCR. To successfully colonize rapeseed roots, the V. longisporum strain 43 pathogen suppressed the biosynthesis of JA, ET and SA hormones in non-primed plants. Priming led to fast and strong systemic responses of JA, ET and SA biosynthesis and signalling gene expression in each leaf, stem and root tissue. Moreover, the quantification of plant hormones via UHPLC-MS analysis revealed a 1.7- and 2.6-fold increase in endogenous JA and SA in shoots of primed plants, respectively. In roots, endogenous JA and SA levels increased up to 3.9- and 2.3-fold in Vl43-infected primed plants compared to non-primed plants, respectively. Taken together, these data indicate that microbial priming stimulates rapeseed defence responses against Verticillium infection and presumably transduces defence signals from the root to the upper parts of the plant via phytohormone signalling. [ABSTRACT FROM AUTHOR]

The persistence of beneficial microorganisms in the rhizosphere or surrounding soil following their application is a prerequisite for the effective interaction with the plant or indigenous microbial communities in the respective habitats. The goal of the study was to analyze the establishment and persistence of the applied beneficial Trichoderma harzianum (OMG16) strain in the maize root-associated soil depending on agricultural practice (soil management practice, N-fertilizer intensity) in a field experiment. A rapid identification of the inoculated strain OMG16 is essential for its monitoring. We used a culture-based approach coupled to matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis for the rapid identification of the inoculated Trichoderma strain as part of the beneficial microbe consortium (BMc). We isolated 428 fungal isolates from eight treatments of the field experiment. Forty eight percent of the isolated fungi equivalent to 205 fungal isolates were identified as Trichoderma, of which 87% (=179 isolates) were obtained from the fields inoculated with BMc. Gene sequence analysis showed a high similarity of the MALDI-TOF MS-identified Trichoderma, with that of the inoculated Trichoderma harzianum OMG16 confirming the re-isolation of the added beneficial fungus. This study highlighted the use of MALDI-TOF MS analysis as a quick, cost-effective detection and efficient monitoring tool for microbial-based bioinoculants in the field. [ABSTRACT FROM AUTHOR]

The aim of the present study was to assess the effects of inoculation of Trichoderma harzianum, Eisenia fetida and cow dung on the physicochemical quality of paddy straw composting which was carried out for 90 days. The different treatment groups were Paddy straw (T0), Paddy straw + Cow dung (T1), Paddy straw + Cow dung + Eisenia fetida (T2), Paddy straw + Cow dung + Trichoderma harzianum (T3), Paddy straw + Cow dung + Eisenia fetida + Trichoderma harzianum (T4). The ratio of cow dung and paddy straw was 2:1. Among all treatments, T4 was identified as the best treatment for decomposing the paddy straw as it recovered the nutrients within the recommended levels of a high-quality product. The consortium of Trichoderma harzianum, Eisenia fetida and cow dung lowered the total organic carbon (TOC) and C:N ratio by 28.8% and 33.1%, respectively, at pH 6.5. The increase in N (0.87%), P (0.47%), K (2.66%), Ca (0.033%), Mg (0.056%) and Na (0.42%) was significant in T4 treatment. The micronutrients, namely Cu (47.9 ppm), Fe (1128 ppm) and Zn (500 ppm), also showed a significant increase in this treatment, i.e., T4. Therefore, results suggested that combinatorial composting by Trichoderma harzianum, Eisenia fetida and cow dung is quite promising in the decomposition of paddy straw to obtain quality compost in a short time. Furthermore, this study will help in the sustainable management of paddy straw with concomitant reduction inenvironmental pollution caused by the open burning of paddy straw. [ABSTRACT FROM AUTHOR]

Take-all disease caused by Gaeumannomyces species bring about economic loses in turfgrass cereals. Surveys were conducted in turfgrass areas in Türkiye and isolations were done from the 318 samples which were taken from irregularly shaped chlorotic patches, and the roots of which are close to dark brown or black. As a consequence of the isolations, fourteen Gaeumannomyces spp. were isolated, and then identifications were performed with rDNA sequence analysis using primers ITS1 and ITS4. Comparison of the ITS sequences with the isolates in the GenBank database, and phylogenetic analysis showed that the isolates belonged to Gaeumannomyces graminis var. graminis, Gaeumannomyces californicus and Gaeumannomyces cylindrosporus. As a result of the pathogenicity tests, virulence of G. graminis var. graminis and G. californicus isolates were higher than that of G. cylindrosporus. Disease severity rates caused by the isolates, as a result of in vitro trials were between 11.83-97.61%, and those in in vivo ranged from 3.70-89.64%. As a result of in vivo tests, it was detected that the most virulent isolate was G. graminis var. graminis numbered 732 followed by 966, 1345, 1369, 1385 and G. californicus numbered 1573, 1925. In this study, the effects of Chaetomium globosum, C. bostrychodes, Sordaria fimicola, Clonostachys rosea, Trichoderma harzianum and T. hamatum fungi, which were previously determined as endophyte species in turfgrass areas, against the most virulent species G. graminis var graminis, were also investigated. As a result of biological control studies, efficacy of C. globosum CG07-1, Chaetomium bostrychodes CB07-2, Trichoderma hamatum Tha34-2 and Trichoderma harzianum TH06-5 strains were found as 86.31%, 83.25%, 70.07, and 64.01% respectively. These strains were found promising in the biological control of 'take-all disease' caused by G. graminis var graminis in turfgrass areas. [ABSTRACT FROM AUTHOR]

Background: Faba bean attacked by soil-borne pathogens causing root rot disease. This disease has serious damage to both plant stand and produced yield. The present study aimed to evaluate effectiveness of the bioagents; Trichoderma harzianum and some plant resistance inducers as fungicide alternatives against root rot disease incidence at both pre- and post-emergence growth stages. Results: Under open greenhouse conditions, the incidence of faba bean root rot in pre- and post-emergence growth phases was considerably reduced by using six inorganic salts and five antioxidants individually or combining with each other or with the bio-stimulator T. harzianum that exceeded the used fungicide, Rhizolex-T. Application of enervit agitated the highest significant defensive impact during pre-emergence stage versus root rot incidence (5.0%), followed by calcium sulfate and [cysteine + T. harzianum] (6.7%). At post-emergence stage, majority of the treatments completely suppressed (100.0%) root rot incidence, except vitamax plus and the fungicide (Rizolex-T) which expressed by 91.7 and 18.8%, respectively. Duplicate irrigations of 23 treatments after faba bean dressing improved the synthesis of different protein contents with the 2nd of which enhanced higher protein contents than the 1st one, except [T. harzianum + vitamin E + vitamin C + enervit + selenium + vitamax plus], [T. harzianum + vitamax plus] and cysteine. Disodium phosphate induced the highest catalase (CAT) activity (1820.8 and 1677.2 U/g FWt) after both irrigations. [T. harzianum + vitamax plus] and vitamin E induced the highest peroxidase (POD) activity 217.4 and 356.9 U/g FWt after 1st and 2nd irrigations, respectively. Disodium phosphate and [T. harzianum + vitamin E + vitamin C + enervit + selenium + vitamax plus] induced the highest chitinase (CHIA) activity 52.8 and 54.4 U/g FWt after 1st and 2nd irrigations, respectively. Application of disodium phosphate, calcium sulfate, potassium metabisulfite, sodium sulfate, cysteine, [cysteine + potash alum], enervit, vitamin E, [vitamin E + vitamin C + enervit + selenium + vitamax plus], [T. harzianum + enervit], [T. harzianum + selenium], [T. harzianum + vitamin E], [T. harzianum + vitamin E + vitamin C + enervit + selenium + vitamax plus] and vitamin C stimulated the formation of new protein bands on SDS-PAGE after the 2nd irrigation treatment. Conclusions: Such treatments are considered good and environmentally safe alternatives against root diseases for getting rid of the negative effects of fungicides. [ABSTRACT FROM AUTHOR]

Influence of fungicides, nutrients and bioagents on yield, quality enhancement and management leaf twisting in onion was studied at Regional Agricultural Station, Vijayapur, Karnataka, during kharif and rabi 2021-22. The variety of 'Bhima Super' seeds collected from two sources (normal and twisting affected seeds) with nine treatments combination of polymer (3 ml kg-1), chemicals, captan (2 g/kg), carboxin 37.5 % + thiram 37.5 % (3 g kg-1), captan 70 % + hexaconazole 5 % (3 g kg-1) and bioagents of Trichoderma harzianum, Pseudomonas fluorescens, and Bacillus subtilis each @ 5 g kg-1. The results obtained from combination of all three bioagents recorded significantly higher bulb yield (23.82 t ha-1) followed by all three bioagents along with fungicides carboxin 37.5 % + thiram 37.5 % (3 g kg-1) (23.15 t ha-1) as compared to control (15.22 t ha-1) due to significant increase in the yield attributes. Kharif harvested bulbs treated with nine different treatment combinations and planted during Rabi season to know the effect of nutrients, fungicides and bioagents on field performance and management of leaf twisting. Among treatments application of N: P: K @ 125: 50: 125 kg ha-1 + Mg @ 30 kg ha-1 + S @ 45 kg ha-1 + B @ 3 kg ha-1 + Zn @ 4 kg ha-1 + foliar spray of hexaconazole 0.05 % at 30 and 60 days after planting recorded significantly higher plant growth parameters, lesser leaf twisting (17.44 %) and higher seed yield (504.49 kg ha-1) as compared to control (34.99 % and 312.47 kg ha-1 respectively). [ABSTRACT FROM AUTHOR]

Black pepper (Piper nigrum L.) is one of the most commonly used spice crops. Foot rot caused by Phytopthora capsici is a major bottleneck in black pepper production, resulting in significant crop losses in pepper-growing areas. To address this issue, a field study was conducted to test the efficacy of potential fungicides, bioagents, and botanicals in combination at two locations during 2017-18. It was found that soil application of Trichoderma harzianum @ 50 g/vine + neem cake @ 1 kg/vine before the onset of monsoon followed by drench and spray with fenamidone + mancozeb @ 2g/lit thrice at monthly intervals had the least leaf infection (7.52%), foliar yellowing (5.38%), defoliation (2.17%), and resulted in the highest dry pepper yield 4.70 kg/vine, with a higher benefit-cost ratio. These findings suggest that the use of a combination of bioagents, fungicides, and botanicals can effectively manage Phytophthora foot rot in black pepper cultivation, leading to increased yield and higher profitability for farmers. [ABSTRACT FROM AUTHOR]

Background: Clusterbean is an important legume crop in arid and semi-arid regions of Rajasthan. It provides livelihood security to arid zone farmers. Bacterial leaf blight (BLB) and root rot are two important diseases of clusterbean which limits its production and productivity. Although, management of these diseases are possible through fungicides. However, in present study focus on use of bio agents which are friendly to the environment. Methods: Field experiment was conducted at ARS, SKRAU, Bikaner, Rajasthan during three consecutive kharif seasons of 2017 to 2019. The experiment was conducted on cv. RGC-1033 with six different combination of Trichoderma harzianum and Pseudomonas fluorescens bio-agents viz, seed treatment, soil treatment and their combinations against the root rot disease and compared with an untreated control. Conclusion: Seed treatment with a combination of T. harzianum + P. fluorescens (4+4 g/kg seed) along with soil application of T. harzianum + P. fluorescens (1.25 +1.25 kg in 50 kg FYM for each/ha) was an effective treatment which reduced root rot incidence and increased seed yield under field conditions. It can be recommended to the cultivators of clusterbean for enhancing yield. [ABSTRACT FROM AUTHOR]

Aims In order to be competitive on the market, the production of biopreparations needs to be optimized, modelled, and assessed in the early stages of its development. The aim of this paper was to optimize medium for the production of Trichoderma harzianum K179 biocontrol agent, to analyze its kinetics at enlarged laboratory scale and finally economic analysis of the production of this high-value product through simulation modelling. Methods and results The results showed that the bioprocess of T. harzianum K179 bioagent production in a laboratory bioreactor on the medium with optimal composition (dextrose 10 g l−1, soy flour 6.87 g l−1, K2HPO4 1.51 g l−1, KCl 0.5 g l−1, and MgSO4 × 7H2O 0.5 g l−1), at stirring speed of 1.75 × g and aeration intensity of 1.5 vvm, can be shortened from 96 to 36 h. The results of bioprocess economic analysis showed that with a 25-year project lifetime and an investment payback time of 7.58 years, this project represents an economically viable system. Conclusions Complete analysis of the bioprocess of T. harzianum K179 biocontrol agent production showed that the biologically produced preparation can be competitive on the market with synthetic preparations. [ABSTRACT FROM AUTHOR]

Pathogenic root/wood rot fungal species infect multiple urban tree species in Singapore. There is a need for sustainable and environmentally friendly mitigation. We report the local Trichoderma strains as potential biocontrol agents (BCAs) for pathogenic wood rot fungal species such as Phellinus noxius, Rigidoporus microporus, and Fulvifomes siamensis. Isolated Trichoderma strains were DNA-barcoded for their molecular identities and assessed for their potential as a BCA by their rate of growth in culture and effectiveness in inhibiting the pathogenic fungi in in vitro dual culture assays. Trichoderma harzianum strain CE92 was the most effective in inhibiting the growth of the pathogenic fungi tested. Preliminary results suggested both volatile organic compound (VOC) production and direct hyphal contact contributed to inhibition. SPME GC-MS identified known fungal inhibitory volatiles. Trichoderma harzianum strain CE92 hyphae were found to coil around Phellinus noxius and Lasiodiplodia theobromae upon contact in vitro and were possibly a part of the mycoparasitism. In summary, the work provides insight into Trichoderma inhibition of pathogenic fungi and identifies local strains with good potential for broad-spectrum BCAs against root/wood rot fungi in Singapore. [ABSTRACT FROM AUTHOR]

The transcription factor THCTF1 from Trichoderma harzianum, previously linked to the production of 6-pentyl-2H-pyran-2-one (6-PP) derivatives and antifungal activity against Fusarium oxysporum, has been related in this study to conidiation, production of an array of volatile organic compounds (VOCs) and expression of methyltransferase genes. VOCs emitted by three T. harzianum strains (wild type T34, transformant ΔD1-38 that is disrupted in the Thctf1 gene encoding the transcription factor THCTF1, and ectopic integration transformant ΔJ3-16) were characterized by Proton Transfer Reaction-Quadrupole interface-Time-Of-Flight-Mass Spectrometry (PTR-Qi-TOF-MS). Thctf1 disruption affected the production of numerous VOCs such as the antifungal volatiles 2-pentyl furan and benzaldehyde which were under-emitted, and acetoine, a plant systemic defense inductor, which was over-emitted. Biological assays show that VOCs regulated by THCTF1 are involved in the T. harzianum antifungal activity against Botrytis cinerea and in the beneficial effects leading to Arabidopsis plant development. The VOC blend from the disruptant ΔD1-38: (i) inhibited Arabidopsis seed germination for at least 26 days and (ii) when applied to Arabidopsis seedlings resulted in increased jasmonic acid- and salicylic acid-dependent defenses. [ABSTRACT FROM AUTHOR]

Endolichenic fungi are considered a promising source of new materials. For further evaluation of some biological activities of the Trichoderma strains isolated from lichens Dirinaria spp. and Cryptothecia spp., their antifungal and antibacterial activities were screened by the methods of dual culture and environmental toxicity. Substrate degradation was evaluated using the qualitative enzyme assays. Fourteen strains of Trichoderma spp. were isolated from 60 lichen samples. All the isolates were able to inhibit the radial growth of tested fungal strains (Bipolaris spp., Colletotrichum spp., Corynespora cassiicola, and Fusarium spp.). Otherwise, only 12/14 isolates were found capable of competing for substrates with Ralstonia solanacearum. The cell-free supernatant obtained from the cultures possessed both antifungal and antibacterial activities. The antagonistic activity of the isolates was selective. Most of the isolates were able to degrade at least one of the investigated substrates, namely cellulose, pectin, and starch. All strains could produce peroxidase; none of the isolates possessed laccase and tyrosinase. A potential antagonistic fungal strain VDT6 has been identified as Trichoderma harzianum. The assessment results indicated that the Trichoderma isolates could be used in agriculture as biological control agents. [ABSTRACT FROM AUTHOR]

The global pandemic of disease COVID-19 caused by the pathogenic SARS-Cov-2 virus brought more interest in the public health community for known silver with its potential antimicrobial properties to fight infection. One of the ways to stop virus to protect community transmission is the application of nanotechnology of silver nanoparticles on the exposed surfaces of daily used materials in public, e.g., transportation, community spaces, hospitals, and everywhere where the potential infection load is increased. Published technology to coat AgNPs on surfaces differs in the preparation of nanocomposites and substrates, which results in different mechanical and antimicrobial properties. In our study, we focused on the properties of AgNPs prepared by HiTUS and PVD technology with a challenge to test the antimicrobial effect towards the model of gram-negative bacteria (Escherichia coli), fungi (Trichoderma harzianum) and related enteroviruses (Poliovirus and Coxsackie). All tested materials showed 59% or more growth inhibition of E. coli. Growth of T. harzianum was inhibited by 16% in the presence of AgTiB2 50W, and other materials caused 37% to 68% inhibition. Enteroviruses infection was completely inhibited after 1 hour of AgNPs treatment. Only Coxsackie A7 retained infection capability after 30 minutes of treatment with AgNPs. Moreover, the ICP-OES-measured amounts of silver released in cultivation media are lower than most published studies of silver nanoparticles with a comparable antimicrobial effect. Keeping silver concentration at the lowest possible limit is one of the most critical factors for producing environmentally safe antimicrobial materials for everyday use. [ABSTRACT FROM AUTHOR]

Damping-off, crown rot, and root rot caused by Fusarium oxysporum and Pythium spp. are important diseases that reduce the growth of cannabis plants and cause mortality. There are currently limited management options available to producers in the absence of registered chemical fungicides. The comparative efficacy of five biological-control agents in reducing disease severity was evaluated in this study. Rhapsody® ASO (Bacillus subtilis), Stargus® (Bacillus amyloliquefaciens), Lalstop® (Gliocladium catenulatum, Prestop®), RootShield® Plus WP (Trichoderma harzianum and Trichoderma virens), and Asperello® (Trichoderma asperellum) were applied to cannabis cuttings in rockwool blocks followed 48 hr later by inoculation with a F. oxysporum spore and mycelial suspension. Disease was rated 7, 14 and 21 days post-inoculation. The most effective treatments were Lalstop, Rootshield, Asperello and Stargus, which provided a significant (P < 0.05) reduction (30 to 56.3%) in mean disease severity 14 days post-inoculation compared to the Fusarium inoculated control. Application of Rootshield, Asperello and Lalstop resulted in endophytic colonization of cannabis cuttings when assessed after 2 and 7 days. For Pythium biocontrol, Rootshield Plus WP, Asperello, and Lalstop were applied as a drench to rooted plants 7 days before inoculation with P. myriotylum. Based on disease severity ratings and plant measurements in two experiments, the most effective treatments were Rootshield and Lalstop. Plants receiving Lalstop or Rootshield had significantly (P < 0.05) higher fresh root weights compared to the pathogen only treatment. These results indicate that several biological control agents can protect cannabis plants from infection by Fusarium and Pythium spp. through pre-emptive colonization. [ABSTRACT FROM AUTHOR]

Background: Plasmopara viticola, the causal agent of grape downy mildew, is one of the most serious grape diseases. Application of Trichoderma harzianum grown on different potato dextrose supplemented broth media using some chemical inducers (TSDCIS), i.e., thiamine (T2), a mixture of micronutrients (T3) and potassium tartrate (T4), compared to Trichoderma without amendment (T1), was conducted under field conditions to evaluate the potential of T. harzianum against grape downy mildew, improving the growth, as well as the yield quality, and quantity. Results: Foliar application of all TSDCIS significantly reduced the disease severity and increased the phenolic content, peroxidase, polyphenol oxidase enzyme activity, growth parameters, and yield parameters. Trichoderma growing on medium supplemented with potassium tartrate (T4) achieved the most significant reduction in the disease severity (78.9, 81.8%) than the control treatment in two growing seasons, respectively. In contrast, it decreased H2O2 content, lipid peroxidation, and cellular electrolyte leakage. Scanning electron microscopy observations revealed that the number of opened stomata, average stomatal area, and stomatal pore area decreased significantly in response to T4 treatment. Conclusions: It can be concluded that using Trichoderma growing on medium supplemented with potassium tartrate (T4) to biosafety control the downy mildew disease of grape and improve its growth, yield, and fruit quality is recommended. [ABSTRACT FROM AUTHOR]

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Cellulases are a class of enzymes of great industrial interest that present several strategic applications. However, the high cost of enzyme production, coupled with the instabilities and complexities of proteins required for hydrolytic processes, still limits their use in several protocols. Therefore, enzyme immobilization may be an essential tool to overcome these issues. The present work aimed to evaluate the immobilization of cellulolytic enzymes of the commercial enzyme cocktail Celluclast® 1.5 L in comparison to the cellulolytic enzyme cocktail produced from the wild strain Trichoderma harzianum I14-12 in Accurel® MP1000. Among the variables studied were temperature at 40 °C, ionic strength of 50 mM, and 72 h of immobilization, with 15 m·L −1 of proteins generated biocatalysts with high immobilization efficiencies (87% for ACC-Celluclast biocatalyst and 95% for ACC-ThI1412 biocatalyst), high retention of activity, and specific activities in the support for CMCase (DNS method), FPase (filter paper method) and β-glucosidase (p-nitrophenyl-β-D-glucopyranoside method). Presenting a lower protein concentration (0.32 m·L−1) than the commercial Celluclast® 1.5 L preparation (45 m·L−1), the ACC-ThI1412-derived immobilized biocatalyst showed thermal stability at temperatures higher than 60 °C, maintaining more than 90% of the residual activities of FPase, CMCase, and β-glucosidase. In contrast, the commercial-free enzyme presented a maximum catalytic activity at only 40 °C. Moreover, the difference in molecular weight between the component enzymes of the extract was responsible for different hydrophobic and lodging interactions of proteins on the support, generating a robust and competitive biocatalyst. [ABSTRACT FROM AUTHOR]

This study was aimed at evaluating the two isolates of the bio-resistant fungi, Trichoderma harzianum and T. koningii in management of the fungus that causes Alternaria alternata leaf spot disease in tomato plants by inducing systemic resistance in the plant. It was demonstrated that two isolates of the pathogenic fungus, A. alternata could infect tomato seeds on water agar media. Isolate No. 1 was the most successful, with an infection rate of 63%, while isolate No. 2 achieved an infection rate of 56%. When employed in concentrations of (10, 20, or 30%) with PDA culture medium, bio-resistant fungus filtrate demonstrated suppression of the pathogenic fungus A. alternata, with the enhanced levels of inhibition with increasing concentration used. Oxacycloheptadec-8-en-2-one, compound 9,12-Octadecadienoic acid, methyl ester, and many more chemical compounds with the ability to inhibit fungi were discovered via the use of the GC-MS equipment to analyze the fungal infiltrates produced by T. harzianum and T. koningii. The bio-resistant fungi significantly lessened the severity of the infection caused by the pathogenic fungus, A. alternata, reaching a reduction of 33.81% during treatment with T. harzianum as opposed to injury of 56.855% in pathogen alone. The tomato leaves that were treated with T. konhngii produced the maximum phenolic content (0.56 mg/g). [ABSTRACT FROM AUTHOR]

The antifungal activity of the Trichoderma harzianum strain IPL/VT/102 against the Fusarium wilt causing pathogen (Fusarium oxysporum) under in vitro and field conditions were determined. Studies were conducted using a commercial formulation of T. harzianum strain IPL/VT/102 (under the trade name of Bioharz). Field trials were conducted in the Bijnor district of Uttar Pradesh for 2 consecutive years (2020-2022). Under in vitro conditions, four sub spp. of F. oxysporum were screened: capsci, vasinfactum, cumini, and zingiberi. <50% inhibition was recorded for all the F. oxysporum subspecies except F. oxysporum f. sp. capsici, where 53.33% inhibition was observed. Based on in vitro results obtained, F. oxysporum f. sp. capsici was selected for a field trial as it showed maximum inhibition. Microscopic examination showed that most of T. harzianum strain IPL/VT/102 spores grew over the mycelia of the F. oxysporum and inside the mycelium, causing lysis of hyphae and collapse of mycelium. Results obtained from the field trials indicated that T. harzianum strain IPL/VT/102 effectively controlled the Fusarium wilt of chili after 30 days of product application, controlled the disease significantly and improved plant growth and yield. [ABSTRACT FROM AUTHOR]

Applying organic amendments and bioagents is considered an ecofriendly practice to promote soil fertility and suppressiveness against many pathogens. This study determined the suppressiveness of seven different organic amendments and four bioagents against the cumin wilt disease at the Department of Plant Pathology, College of Agriculture, Jodhpur (Agriculture University Jodhpur) in the years 2020-2021. Among them, the lowest incidence was recorded in mustard cake (27.11%), neem cake (29.37%), groundnut cake (29.96%), and sesame cake (31.81%). Disease incidence was higher in other amendment applications like castor cake (33.21%) and cotton cake (33.14%). However, the disease incidence was much higher in controls (64.11%). Among bioagent treatments in vitro, Trichoderma harzianum (78.25%) and Trichoderma viride (72.69%) were the best at inhibiting the mycelial growth of Fusarium oxysporum f. spp. cumini compared to the treatment of Bacillus subtilis (55.34%). [ABSTRACT FROM AUTHOR]

Food waste anaerobic digestion biogas residue contains high organic matter and nutrient elements, which can be used as raw materials for composting to obtain organic fertilizer products. In this paper, four bacterial agents, namely Bacillus subtilis, Aspergillus niger, EM bacteria, and Trichoderma harzianum, were selected as the mixed original bacterial strains, with a total additional amount of 2 kg of bacterial agent and a 3 tons pile of fertilizer. Five groups of different mixed ratios, R1 to R5 (mass addition ratio: were used as evaluation indicators, including seed germination index, temperature rise rate, and C/N consumption rate. The results showed that group R4 had the best heating effect, the fastest rate, and the largest C / N reduction rate. The final seed germination index (GI) reached over 80%, and the organic matter content was greater than 45%. The R1 group had a seed germination index >110%, which had a significant promoting effect on plant germination. In the addition of bacterial agents, a large amount of Bacillus subtilis could increase the number of microbial communities in the pile. The addition of Aspergillus niger and EM bacteria could advance the ripening period and accelerate stabilization. Meanwhile, due to the large volume of the pilot test reactor and the complexity of the test environment, there were many influencing factors. Compared with the small-scale test, it had a more stable temperature change, which was more conducive to the degradation, harmless treatment, and microbial activity of organic matter in the reactor. Although there were more microorganisms and uncontrollable factors, their harmless effects and composting products are more stable. [ABSTRACT FROM AUTHOR]

Salinity is a significant concern in crop production, causing severe losses in agricultural yields. Ocimum sanctum, also known as Holy Basil, is an important ancient medicinal plant used in the Indian traditional system of medicine. The present study explores the use of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase-producing strains of plant-growth-promoting bacteria (PGPB) namely Str-8 (Halomonas desiderata), Sd-6 (Brevibacterium halotolerans), Fd-2 (Achromobacter xylosoxidans), Art-7 (Burkholderia cepacia), and Ldr-2 (Bacillus subtilis), and T. harzianum (Th), possessing multi-functional properties like growth promotion, stress alleviation, and for enhancing O. sanctum yield under salt stress. The results showed that co-inoculation of Th and PGPBs enhanced plant height and fresh herb weight by 3.78–17.65% and 7.86–58.76%, respectively; highest being in Th + Fd-2 and Th + Art-7 compared to positive control plants. The doubly inoculated plants showed increased pigments, phenol, flavonoids, protein, sugar, relative water content, and nutrient uptake (Nitrogen and Phosphorous) as compared to monocultures and untreated positive control plants. In addition, co-inoculation in plants resulted in lower Na+, MDA, H2O2, CAT, APX activities, and also lower ACC accumulation (49.75 to 72.38% compared to non-treated salt- stressed plant) in O. sanctum, which probably played a significant role in minimizing the deleterious effects of salinity. Finally, multifactorial analysis showed that co-inoculation of Th and PGPBs improved O. sanctum growth, its physiological activities, and alleviated salt stress compared to single inoculated and positive control plants. These microbial consortia were evaluated for the first time on O. sanctum under salt stress. Therefore, the microbial consortia application could be employed to boost crop productivity in poor, marginalized and stressed agricultural fields. [ABSTRACT FROM AUTHOR]

Virulent infectious fungal diseases, in natural and managed landscapes, are increasing. Fungal diseases in humans, animals and plants have caused die-off and extinction events and have become a threat to food security. A caving expedition in Yunnan Province, China, revealed two bat carcasses covered in fungal mycelia. Eleven fungal isolates were obtained from these bat carcasses, and morphological observations and multigene phylogenetic analyses revealed they were Fusarium incarnatum, Mucor hiemalis and Trichoderma harzianum and four new species, Mortierella rhinolophicola, M. multispora, M. yunnanensis and Neocosmospora pallidimors. One of the more alarming findings is that a number of infections related to Neocosmospora, previously associated with human and animal mycotoxicoses, are reported to be increasing, and here we present a new species from this genus, isolated from dead bats. Due to the ecosystem services provided by bats, and the close relationship between bats and humans, future research should focus on the impacts and significance of N. pallidimors to human and animal health, examining its pathogenicity and secondary metabolites. Taxonomic descriptions, color images of the habitat, in situ samples, microstructures and cultures are presented. SEM photographs of microstructures and phylogenetic trees showing the placement of new and known species are also provided.

Abstract Background Meloidogyne incognita (Kofoid and White) Chitwood is a major pest of eggplant in Pakistan. The second-stage juveniles (J2s) feed on the roots of eggplant. Damaged roots swell and the plant exhibits stunted growth. Mostly farmers rely on the use of broad-spectrum nematicides. However, due to hazardous effects on the environment and non-target species, its application is greatly criticized. Fungal biocontrol agents have been long used for curtailing root-knot nematode infections. The present study was conducted to determine the virulence of four fungal biocontrol agents against M. incognita under laboratory and greenhouse conditions. Results The in vitro results revealed that Trichoderma harzianum significantly caused 77.60% egg inhibition, followed by Pochonia chlamydosporium (53.0%) at 1:1 concentration after 72 h. The maximum J2s mortality was achieved by T. harzianum (82.0%), followed by P. chlamydosporium (70.20%) at 1:1 concentration after 72 h. The in-planta examination carried out at a greenhouse demonstrated that the soil drench treatment of fungal biocontrol agents significantly suppressed M. incognita parameters and upraised the eggplant growth. The mean least number of galls (22.25) was in T. harzianum treated plants, while the control had (206.8) galls. Likewise, T. harzianum curtailed the least egg masses to 35.75 and swollen females to 21.12 than control negative (224.13 egg masses and 182.75 swollen females). Conclusion T. harzianum was the best agent to control M. incognita (J2s) effectively, followed by P. chlamydosporum. T. harzianum may be a contribution to the biological control of M. incognita in Pakistan.

The oil palm biomass produced by plantations and mills in Malaysia is the largest contributor to the nation’s agro-waste, with the oil palm leaves (OPL) topping the list. Nevertheless, the surplus of OPL might have applicability as the substrate for cultivating lignocellulolytic bio-degraders. Ipso facto, this study employed raw OPL as the carbon source for cultivating Trichoderma harzianum under solid-state fermentation (SSF). Optimization of the SSF process using the Taguchi orthogonal design to produce endoglucanase (CMCase) successfully established the optimal fermentation conditions as the following: 7.00 × 108 spore/g inoculum size, 50% moisture content, pH 12 Mandel’s medium, with 3-day incubation at 40°C. The crude enzyme cocktail exhibited the corresponding maximum activity of 417.49 U/g CMCase. The enzymatic activities were significantly affected by factors, moisture content, inoculum size, and initial pH (p-value < 0.05). In short, the high extracellular CMCase activity of the T. harzianum crude enzyme cocktail may prove valuable in accelerating the saccharification of cellulose for biofuel-and nanocellulose production.

This study was carried out for the estimation of polyphenols (TP) and induction of oxidative enzymes polyphenol oxidase (PPO) and peroxidase (POD) in sunflower plants through seed immersion in agrochemicals of salicylic acid (SA) and water soluble chitosan (CH) in addition to a conidial suspension of Trichoderma harzianum and then analysis of plant content of carbohydrates and protein. The highest level of PPO 253.3 U ꞏ min –1 was detected in 50 ppm SA for 6 h. Next was T. harzianum when catalyzed PPO with 193.67 U ꞏ min –1. Peroxidase was substantially catalyzed in accordance with the increment of inducers. Sunflower roots induced TP with up to 4.88 mg ꞏ g –1 in plants treated with SA at 50 ppm for 6 h and then declined with an increasing SA dose. The total carbohydrate content in leaves of 320 mg ꞏ 100 g –1 was found in treatments of CH at 50 ppm for 6 h. In roots, a carbohydrate content of 500 mg ꞏ 100 g –1 was observed using CH 75 ppm for 6 h. Trichoderma harzianum remarkably increased proteins in leaves and roots by up to 25% compared to 16.9% in the control. These results suggest that inducing the plants’ own defense mechanism by applying salicylic acid and chitosan and bio-control of T. harzianum may offer alternative methods for controlling charcoal rot of sunflower due to the creation of defensive enzymes and could support plant vigor by enhancement of its protein and carbohydrate content.

A study was conducted to evaluate efficiency of Mycotal at a concentration of 1.2 × 107 spores/ml and the fungus Trichoderma harzianum at concentrations of 1.5 × 106 and 1.5 × 107 spores/ml on nymphs and adults of the whitefly, Bemisia tabaci under field conditions on the eggplant, Solanum melongena. The results revealed that Mycotal active substance is the fungus Lecanicillium muscarium, showed the highest average relative efficiency in killing nymphs and adults in the Mycotal treatment, which amounted to 79.93 and 85.62%, respectively, compared with T. harzianum treatment for the two concentrations, which amounted to 60.76 and 67.76% for nymphs and 69.55 and 72.19% for adults, respectively under field conditions. The results also showed that the Mycotal achieved the best relative efficiency in killing whitefly adults, which amounted to 78.5, 86.07, and 92.3% after 3, 5, and 7 days, respectively, with a significant difference compared to the concentrations of the fungus T. harzianum, which were 52.35, 75.60, and 80.70% at a concentration of 1.5× 106 spores/ml and 55.10, 78.37 and 83.08% at concentration of 1.5 x 107 spores/ml after 3, 5 and 7 days of treatment, respectively.

Geranium (Pelargonium graveolens L’Herit ex Ait.) plants infected with root rot and wilt diseases were collected from different locations of Behira, Ismailia and Minia Governorates, Egypt. Fusarium, Macrophomina, Rhizoctonia and Pythium were isolated from the infected plants. The results showed that F. oxysporum recorded the highest isolated rate, followed by R. solani, F. solani, M. phaseolina and Pythium sp. The effect of various concentrations of marjoram and peppermint essential oils on the mycelial growth of the isolated fungi was tested in vitro. Marjoram and peppermint oils completely inhibited the growth of F. oxysporum, F. solani, R. solani and Pythium sp. at the concentration of 5 ml/l. A Field experiment was conducted at the Experimental Farm of Agricultural Research Station, Malawy, Minia Governorate, Egypt, during two successive seasons of 2020 and 2021 to study the effect of different weed control methods (un-weeded control, clover cover yield, hand hoeing and black plastic mulch) on weeds biomass. The results indicated that all weed control treatments significantly decreased the weight of grassy broad-leaf weeds and total weeds compared to the un-weeded control. Moreover, all weed control treatments and plants treated with the essential oils of marjoram and peppermint as well as the biocides (Bacillus subtilis and Trichoderma harzianum) significantly decreased the wilt disease incidence and improved the vegetative growth, yield and volatile oil of geranium plants. The results indicated that plastic mulch was the most effective in reducing wilt incidence as well as increasing all growth characteristics and productivity of volatile oil, while the highest disease incidence and the lowest growth and yield were recorded under un-weeded treatment. The application of the marjoram essential oil or biocide B. subtilis resulted in the lowest incidence of wilt disease and the highest increase in the growth, herb yield, essential oil yield and main components of essential oil. The highest growth characters and volatile oil were recorded with either black plastic mulch and marjoram essential oil or with B. subtilis treatment.

Cayenne pepper (Capsicum frutescens L.) is a horticultural plant that has high economic value and contains nutrients that the body needs. Cayenne pepper is one of the leading national horticultural commodities, so it is necessary to increase the production of cayenne pepper appropriately. The obstacle that is often faced in the production of cayenne pepper is the disruption of the production of cayenne pepper caused by the attack of anthracnose disease. Anthracnose disease or fruit rot caused by the fungus Colletotrichum capcisi Sydow can result in yield losses ranging from 20-90%. Trichoderma harzianum Rifai. is a soil saprophytic fungus that naturally can be used as a biological agent, because it has antagonism against pathogens in the form of competition for space and nutrients, mycoparasites and antibiosis. The experimental results in the laboratory showed that the biological agent Trichoderma harzianum Rifai was able to suppress the development of anthracnose disease.

Background: Apple decline diseases, responsible for seedlings root and collar rot in nurseries, are an important disease. Different fungal and bacterial antagonists were evaluated to control Pythium ultimum associated with this serious disease using in vitro and in vivo greenhouse assays. Results: The in vitro test of ten Aspergillus spp. and ten Trichoderma harzianum isolates showed their efficacy to reduce the radial growth of P. ultimum. The isolates, A. niger A10, A. candidus A5, T. harzianum Tr9 and Tr10, were the most effective with a high inhibition percent that exceeded 50%. The in vivo test of the four most effective antagonists and a strain of Bacillus subtilis (B) showed that the combination of the two Aspergillus isolates (A5 and A10) gave the best result with a decrease in root browning index by 55.55%. Results showed also the efficacy of all tested antagonists and their combinations on the sanitary state index of the inoculated plants except the combination between T. harzianum (Tr10) and B. subtilis (B). The two treatments, T. harzianum (Tr10) and B. subtilis (B), significantly improved the height of inoculated plants by 173.19 and 191.3%, respectively. Regarding the efficacy of antagonists on apple seedlings root weight, A. niger (A10) was the only treatment that significantly increased this parameter by 363.17%. Conclusions: A. niger A10, A. candidus A5, T. harzianum Tr9 and Tr10 exhibited the highest value of in vitro inhibition to growth of P. ultimum. The combination of A. niger A10 and A. candidus A5 was the most effective in vivo treatment in reducing the disease severity index. However, T. harzianum (Tr10), B. subtilis (B) and A. niger (A10) revealed to be able to stimulate the apple seedlings growth. [ABSTRACT FROM AUTHOR]

Soil disinfection using high temperatures via steam is a promising approach to manage plant pathogens, pests, and weeds. Soil steaming is a viable option for growers who are moving away from dependence on chemical soil fumigants, especially in plant nursery or high tunnel environments. However, there are few studies that investigate how soil steaming causes substantial disturbance to the soil by killing both target pathogens and other soil biota. Steaming treatments also change the trajectory of the soil microbiome as it reassembles over time. Growers are interested in the health of soils after using steam-disinfection, especially if a virulent pathogen colonizes the soil and then flourishes in a situation where there are very few microbes to suppress its growth. Should recruitment of a virulent pathogen occur in the soil, this could have devasting effects on seed germination, seedling establishment and survival. Beneficial microbes are often used to prevent the colonization of plant pathogens, especially after a soil-steaming event. Here, we experimentally test how soil fungal communities assemble after steaming disinfection. We introduce to steam-treated soil Fusarium solani, an important fungal pathogen of soybean and Trichoderma harzianum, a known beneficial fungus used for soilborne pathogen suppression. Results show that F. solani significantly affects the relative abundance and diversity of the soil fungal microbiome, however, T. harzianum does not mitigate the amount of F. solani in the steam treated soil. Within the T. harzianum microbial addition, the soil fungal communities were similar to the control (steaming only). This result suggests inoculating the soil with T. harzianum does not drastically alter the assembly trajectory of the soil fungal microbiome. Other soil amendments such as a combination of Trichoderma spp. or other genera could suppress F. solani growth and shift soil microbiome composition and function post-steaming, however, more experimental research is needed. [ABSTRACT FROM AUTHOR]

Trichoderma atroviride and Trichoderma harzianum are widely used as commercial biocontrol agents against plant diseases. Recently, T. harzianum IOC-3844 (Th3844) and T. harzianum CBMAI-0179 (Th0179) demonstrated great potential in the enzymatic conversion of lignocellulose into fermentable sugars. Herein, we performed whole-genome sequencing and assembly of the Th3844 and Th0179 strains. To assess the genetic diversity within the genus Trichoderma, the results of both strains were compared with strains of T. atroviride CBMAI-00020 (Ta0020) and T. reesei CBMAI-0711 (Tr0711). The sequencing coverage value of all genomes evaluated in this study was higher than that of previously reported genomes for the same species of Trichoderma. The resulting assembly revealed total lengths of 40 Mb (Th3844), 39 Mb (Th0179), 36 Mb (Ta0020), and 32 Mb (Tr0711). A genome-wide phylogenetic analysis provided details on the relationships of the newly sequenced species with other Trichoderma species. Structural variants revealed genomic rearrangements among Th3844, Th0179, Ta0020, and Tr0711 relative to the T. reesei QM6a reference genome and showed the functional effects of such variants. In conclusion, the findings presented herein allow the visualization of genetic diversity in the evaluated strains and offer opportunities to explore such fungal genomes in future biotechnological and industrial applications. [ABSTRACT FROM AUTHOR]

[Objectives]The aim of this study was to screen M95 which was mutant strains of Trichoderma harzianum with high yield of 3-indoleacetic acid (IAA) by irradiation with high-energy rays, and evaluate its growth-promoting effect on plants. [Methods]The mutant library of Trichoderma harzianum was obtained by X-ray irradiation, and the mutant strain M95 with the highest yield of IAA was screened by Salkowski colorimetry and high performance liquid chromatography (HPLC). Then the carbon source utilization characteristics of high-yielding IAA mutants were studied by the Biolog FF MicroPlateTM. The expression levels of auxin biosynthesis-related genes in M95 were detected by quantitative real-time PCR. Finally, the growth-promoting effect of M95 on cucumber was investigated by hydroponics and pot experiments. [Results]Thirty-eight mutants were screened from the mutant library. The IAA production of M95 was 20.51% higher than that of the wild type. The results of the Biolog FF MicroPlateTM showed that M95 grew fastest and significantly faster than the wild strain NJAU 4742（WT）under the condition of D-fructose as the sole carbon source. Quantitative PCR results showed that the transcript levels of acetamide dehydrogenase gene iaaH2 and nitrilase gene nit2 increased by 32.68 and 14.58 times, respectively, compared with WT. The growth-promoting effect of M95 on cucumber seedlings was significantly better than that of WT. Relative to WT,cucumber plant height, leaf area, below ground fresh weight and dry weight in the M95 treatment increased by 14.79%,16.84%,31.41% and 47.96% in the hydroponic condition, 20.99%,13.92%,17.92% and 34.02% in the first season pot trial, respectively, and 12.23%,15.15%,23.29% and 30.02% in the second season pot trial. In addition, the number of inter-root bacteria, fungi and xylem increased by 1.91%,5.80% and 5.08%,respectively, in the M95 treatment compared to WT in the pot trial. [Conclusions]The IAA high-yielding strain T.harzianum M95 was obtained by screening, and it had a significant promoting effect on the growth of cucumber seedlings. The increase in the transcription levels of acetamide dehydrogenase and nitrilase in M95 was the main reason for the improvement of its IAA-producing ability. [ABSTRACT FROM AUTHOR]