Aims: Trichoderma asperellum strain SD1 grows on 3-chloropropionic acid (3CP), a β-haloalkanoic acid, and produces a putative extracellular dehalogenase that can degrade this acid. Here we further characterized the fungal enzyme system responsible for biodegradation of 3CP. Methodology and results: The primary qualification of the ligninolytic potential in T. asperellum strain SD1 was performed using guaiacol oxidation. When strain SD1 was grown in liquid minimal medium with the presence of 3CP as the sole carbon source, no lignin peroxidase, manganese peroxidase, or laccase activity was detected. The ligninolytic condition was achieved only in the presence of glucose or when guaiacol was present as an inducer. Under nonligninolytic conditions, 3CP was utilized by strain SD1. Therefore, 3CP was utilized under ligninolytic conditions as well as under non-ligninolytic conditions, suggesting that extracellular peroxidases and laccase are not involved in the degradation of 3CP by T. asperellum strain SD1. Conclusion, significance, and Impact of study: Very few studies have explained the degradation of β-chloro– substituted haloalkanoic acids such as 3CP by dehalogenases. This is the first report to identify a novel putative β- haloacid dehalogenase that degrades 3CP under ligninolytic and non-ligninolytic conditions. T. asperellum strain SD1, thus has the potential in the development of dehalogenating enzymes for industrial biocatalytic processes, in future.
Trichoderma

Aims: Meloidogyne incognita adversely affects numerous crop plants worldwide. Therefore, the modern world has been moving towards biocontrol methods to prevent nematode attacks. This study was aimed to (i) investigate the potential use of Trichoderma harzianum NFCF160 and T. virens Isf-77 in managing M. incognita in soil and (ii) identify trapping mechanisms employed by both Trichoderma strains to suppress M. incognita. Methodology and results: Three weeks old, Basella alba L. plants were subjected to five different treatments. The above and below ground growth parameters and the galling indices of these plants were measured every four weeks for three sampling times. Trapping mechanisms employed by Trichoderma strains were examined following plate assays. Plants treated with T. harzianum NFCF160 and T. virens Isf-77 had significantly higher values for the total number of leaves (34 ± 2.84) and (27 ± 2.61), fresh weight of the shoot (81 ± 9.51 g) and (91 ± 9.70 g), dry weight of the shoot (71 ± 5.24 g) and (62 ± 5.81 g), respectively eight weeks after inoculation of M. incognita. Significantly low galling indices (2 and 2) were recorded in B. alba treated with Trichoderma strains. Both Trichoderma strains exhibited various nematode-trapping mechanisms, such as non-constricting rings and adhesive spores. Conclusion, significance and impact of study This investigation highlighted the potential of both Trichoderma strains as biocontrol agents to control M. incognita effect in sustainable agriculture.
Tylenchoidea ; Trichoderma ; Soil Microbiology

Field studies were conducted over two seasons during the summers of 1997 and 1998 to investigate the effects of different spatial arrangements(random or highly aggregated) of sclerotia of Sclerotinia sclerotiorum and alginate pellet types(bran or polyethylene glycol) on colonization of sclerotia by Trichoderma spp. Treatment with alginate pellets increased the mean percentages of sclerotia colonized by Trichoderma spp. in both years. Distribution patterns of sclerotia affected the mean percentage of sclerotia colonized by Trichoderma spp. in both years, indicating that a highly aggregated distribution of sclerotia was more favorable to colonization by Trichoderma spp. The effects of the different pellet types(bran or PEG) were not siginificant in both years(P>0.05). The application of higher densities(200 pellets per 1 m2) of alginate pellets resulted in higher mean percentages of sclerotia colonized by Trichoderma spp. in 1998(p<0.05), but did not in 1997.
Ascomycota* ; Colon* ; Polyethylene ; Seasons ; Trichoderma*

A method of spawn making procedures through the application of fermented sawdust for the purpose of avoiding contamination by undesirable fungi in the course of Pleurotus ostreatus mycelial growth was evaluated. Of three kinds of supplements, rice bran was the most effective to raise temperature up to 70degrees C. Mycelial activity and density was more considerably improved in the case of using fermented sawdust supplemented with rice bran than the case of non-fermented sawdust. Primordia of Pleurotus ostreatus were formed on fermented sawdust. The substrate of fermented sawdust showed potential to prevent the growth of Trichoderma sp. which caused a symptom on mushroom mycelium, whereas there was nothing to inhibit the growth of Trichoderma sp. during 30 days after inoculation in non-fermented sawdust.
Agaricales ; Fungi ; Mycelium ; Pleurotus* ; Trichoderma

Aims: Knowledge of the Trichoderma taxa is important for both control efficiency and environmental conservation. Therefore, the objective of this study is to isolate and identify Trichoderma species from various rhizosphere soil samples using phenotypic and molecular characterization. Methodology and results: Native Trichoderma spp. were isolated from agricultural fields in 17 sites from seven states of Malaysia. These isolates were characterized via morphological observation and molecular phylogenetic analysis based on the translation elongation factor-1α (tef1-α) gene. About 42 isolates were classified into eight Trichoderma species, which are Trichoderma asperellum, T. hamatum, T. harzianum, T. koningiopsis, T. rodmanii, T. spirale, T. viride and T. virens. Comparison of DNA sequences of tef1-α showed that the isolates were 98-100% similar to respective Trichoderma species from GenBank, thus confirming the fungal identity. Phylogenetic trees of maximum likelihood (ML) dataset of tef1-α inferred that the isolates were clustered according to species. Conclusion, significance and impact of study Findings in the present study will be beneficial for the purposes of biodiversity conservation and plant disease management using biocontrol agents.
Trichoderma--isolation & ; purification ; Rhizosphere

The morphological optimization of Trichoderma harzianum was carried out using several surfactants to achieve increased cellulase production. Addition of the surfactants to the culture medium successfully modified the fungal morphology from an aggregated form to a dispersed form. Optimization of the fungal morphology increased cellulase activity up to 177%. The morphologically optimized conditions enhanced the accessibility of the fungus to substrates and thus promoted cellulase production.
Cellulase ; Fungi ; Surface-Active Agents ; Trichoderma*

Perforated vinyl mulching technique was performed on oyster mushroom beds for controlling mushroom diseases. Mycelium under vinyl sheets were safely protected from outside undesirable microorganisms. One of two mushroom farms showed 75% of disease incidence, the other 40% and National Institute of Agricultural Science and Technology (NIAST) 13% in the conventional growing method, whereas 12%, 14%, and 5% in the vinyl mulching cultivation method. Waterlogging caused mushroom bed worse, and Trichoderma spp. were infested on the conventional mushroom bed. Disease incidence investigated in other case was 25% to 30% in the conventional growing method, whereas 5 to 9% in the vinyl mulching cultivation method. Yields in conventional method were 6.5 to 7.2 kg/m2 and those in vinyl mulching method were 7.6 to 8.1 kg/m2. So it was suggested that vinyl mulching technique was good for prevention from disease and elevation of productivity.
Agaricales* ; Efficiency ; Incidence ; Mycelium ; Pleurotus* ; Trichoderma

This paper describes and illustrates two new species, Trichoderma pleurotum and T. pleuroticola, associated with green mold disease of oyster mushroom in Korea.
Classification ; Fungi* ; Korea* ; Ostreidae* ; Pleurotus* ; Trichoderma*

This study was conducted to investigate physiological characteristics of Trichoderma spp. isolated from Pleurotus spp. Damage tests of Pleurotus spp. and mycotoxins tests of Trichoderma spp. were also done. The optimal growth temperature of Trichoderma spp. was 27~30degrees C. Although, T. longibrachiatum was able to grow at 37degrees C and grew 30~40 times faster than Pleurotus. The colony colour on PDA medium of T. cf. virens was yellowish green, T. longibrachiatum was yellow, and T. harzianum was turning to bright green. In damage tests of Pleurotus by Trichoderma, T. cf. virens caused the most severe damage to Pleurotus. T. longibrachiatum and T. harzianum caused less damage on Pleurotus but were able to cause greater damage to P. eryngii. One of the mushroom cultivars, P. ostreatus 8 was the most resistant to all Trichoderma spp.. Chitinolytic mycotoxin released by Trichoderma spp. caused 52.7% damage to Pleurotus. Mycotoxins released by T. longibrachiatum caused the greatest damaged (78.6%) on P. eryngii.
Agaricales ; Fungi* ; Mycotoxins ; Ostreidae* ; Pleurotus* ; Trichoderma

Trichoderma strains were evaluated under field conditions to assay their efficacy in suppressing Alternaria fruit rot disease and promoting chili plant growth. The experiment was conducted at the Botanical Garden, Rajshahi University, Bangladesh from July 2006 to March 2007. Application of Trichoderma harzianum IMI 392432 significantly (p = 0.05) suppressed the disease compared to Alternaria tenuis (T2) treatment and improved both growth and yield. The treatment T4 (T. harzianum IMI-392432 + A. tenuis) was most effective in reducing disease percentage (72.27%) compared to A. tenuis (T1) treatment. The highest seed germination rate (85.56%) and the highest growth and yield (12.5 g/plant) was also recorded in the same treatment (T4), followed by T5 (T. harzianum IMI-392433 000000 + A. tenuis), T6 (T. harzianum IMI-392434 +A. tenuis), T2 (T. virens IMI-392430 + A. tenuis), and T3 (T. pseudokoningii IMI-392431 +A. tenuis) treatment, while single treatment with A. tenuis significantly decreased these values.
Alternaria ; Bangladesh ; Fruit ; Germination ; Plants ; Seeds ; Trichoderma