Antima Sharma

Optimal Physical Parameters for Growth of Trichoderma Species at Varying pH, Temperature and Agitation

The study was aimed to carry out experiments to determine the optimal parameters for the biomass production of Trichoderma. It is quite essential to determine the physical conditions that are favorable for the growth of Trichoderma species. The seven species under study have been isolated from the rhizospheric soils of chickpea; pigeon pea and lentil crops of different areas of an Indian State (Uttar Pradesh) and these were later tested in vitro at different pH, temperatures and varying agitation speed. A significant difference in the biomass production was recorded among the species at tested pH levels i.e. 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5 and 8.0. The most favorable pH ranges between 5.5 and 7.5 in which total dry weight of mycelium varies between 1.41 and 1.35 g. Although all the species of Trichoderma produced sufficient biomass at different temperatures viz. 20°C, 25°C, 30°C and 35°C but they were found to be best grown at a temperature range of 25°C to 30°C. Aeration by agitation was also checked at different speeds such as 100, 150, 200 and 250 rpm but greatest biomass was recorded at 150 rpm.

Phylogenetic diversity analysis of Trichoderma species based on internal transcribed spacer (ITS) marker

The phylogeny of Trichoderma and the phylogenetic relationships of its species was investigated by maximum parsimony analysis and distance analysis of DNA sequences from multiple genetic loci 18S rDNA sequence analysis suggests that the genus Trichoderma evolved at the same time as Hypomyces and Fusarium and thus about 110 Myr ago 28S rDNA sequence analysis shows that the genus Trichoderma is part of a monophyletic branch within the Hypocreaceae. Most isolates of the genus Trichoderma were found to act as mycoparasites of many economically important aerial and soil-borne plant pathogens. Trichoderma has attained importance as a substitute for chemical pesticides and hence an attempt was intended to corroborate the positive relatedness of molecular and morphological characters. Two fungal strains, Trichoderma koningii Tk-5201/CSAU and Trichoderma virens Tvi4177/CSAU were isolated from a soil sample collected from CSA Farm, Kanpur district of Uttar Pradesh, India. The universal primers (internal transcribed spacer, ITS) were used for the amplification of 18S rRNA gene fragment and strains were thus characterized with the help of ITS marker. It is proposed that the identified strains T. koningii Tk-5201/CSAU and T. virens Tvi-4177/CSAU be assigned as the type strains of a species of genus Trichoderma based on phylogenetic tree analysis together with the 18S rRNA gene sequence search in Ribosomal Database Project, small subunit rRNA and large subunit rRNA databases. The sequence was deposited in GenBank with the accession numbers KC800923 and KC800924, respectively. Thus an integrated approach of morphological and molecular markers can be employed to identify a superior strain of Trichoderma for its commercial exploitation.

Enhancing Seed Germination and Vigor of Chickpea by Using Potential and Effective Strains of Trichoderma Species

In this study, potential and effective strains of Trichoderma such as T. harzianum (Th. Azad) and T. viride (01PP) have been investigated and their effect of pre sowing seed treatment on germination, seedling establishment, seedling dry weight and vigour in chickpea genotype (Radhey) was observed. The different pre sowing seed treatments showed different responses against all seven seed quality parameters. Chickpea seeds were treated with different concentrations of Trichoderma bioformulation such as 5%, 10%, 20% gm/kg seed followed by treatment with 0.2% Bavistin. As a result, the percentage of seed germination was found to be higher in T. harzianum (Th. azad) & Trichoderma viride (01PP) treated seeds with 5% bioformulation as compared to the other concentrations. Various attributes with their observations include seed germination (92% and 90%), root length (12.38 and 12.19 cm) shoot length (4.97 and 4.32 cm) seedling length (17.38 and 16.50 cm), dry weight (1.19 and 1.88 cm), vigour index I (5197.12 and 1485) and vigour index II (109.48 and 169.20). Among all treatments, control showed the poorest performance for all seven seed quality attributes.

Role of Secondary Metabolites Produced by Commercial Trichoderma Species and their Effect Against Soil Borne Pathogens

The study was focused on the identification of the major secondary metabolites produced by the Trichoderma spp and soil borne pathogens. Trichoderma harzianum (Th. Azad) and Trichoderma viride (01PP) are two microorganisms used as active agents in a variety of commercial bio pesticides and bio fertilizers and widely applied on field and greenhouse crops. The production, isolation, biological and chemical characterization of the major secondary metabolites produced by these strains is done during this study. Metabolites are organic compounds that are used in, or created by, the chemical reactions happening in every cell of living organisms. In this paper we are studying about the production of secondary metabolites from Trichoderma species against soil borne pathogens at 27oC at different time intervals. Higher the concentration of secondary metabolites, greater will be the efficiency against soil borne pathogens