Types of trichoderma selective media
Trichoderma Selective Media (TSM) is a specialized agar-based formulation that is extensively utilized in the field of microbiology to selectively isolate and culture Trichoderma species, which are renowned for their beneficial attributes as fungi. TSM provides an optimal environment for the growth and identification of these specific fungal species, thereby facilitating extensive research and applications in various industries such as agriculture, biotechnology, and environmental science.- **Purpose**: TSM is meticulously designed to favor the growth of Trichoderma while effectively suppressing the growth of other microorganisms. This selective nature of the media simplifies the process of identifying and studying these fungi.
- **Components**: TSM typically contains a carbon source, such as glucose, and various selective agents including:
- **Rose Bengal**: This component restricts the size of fungal colonies, thereby making Trichoderma more distinguishable.
- **Antibiotics**: Examples include chloramphenicol or streptomycin, which effectively inhibit bacterial growth within the media.
- **Fungicides**: Compounds like pentachloronitrobenzene (PCNB) are incorporated to effectively suppress non-target fungi.
- **pH Indicator**: Some formulations of TSM may include a pH indicator, such as phenol red, to monitor pH changes. These changes can be indicative of fungal growth and aid in the assessment of the media’s effectiveness.
TSM is widely used by researchers to study Trichoderma's important function in agriculture, such as its capacity to promote plant development, guard against diseases, and improve soil health. It is important to note that the precise TSM formulation can differ greatly depending on the Trichoderma species being targeted and the environmental sample being studied.
Rose Bengal agar (RBA)
Jarvis created RBA, a nonselective medium for isolating Trichoderma, in 1973 to count moulds and yeasts in food samples. The media is appropriate for protein foods and can withstand high temperatures. Chloramphenicol or chlortetracycline is used to inhibit bacterial growth
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| Microscopic staining picture of trichoderma |
Recipe for rose Bengal agar (RBA)
1. Mycological peptone 5.0 g
2. Rose Bengal 0.05 g
3. Glucose 10.0 g
4. Chloramphenicol 0.1 g
5. Dipotassium phosphate 1.0 g
6. Agar 15.0 g
7. MgSO4.7 H20 0.5 g
8. Distilled 1000 mL
Trichoderma harzianum selective medium (THSM)
Selection of THSM enables comparison between aggressive and non-aggressive
Trichoderma groups. The antimicrobials chloramphenicol, streptomycin, quintozene,
and propamocarb are added to the medium to highly select T. harzianum in compact
colonies without visible contamination [23].
Recipe for THSM
1. 0.2 g of MgSO4∙7H2O.
2. 0.9 g of K2HPO4.
3. 1.0 g of NH4NO3.
4. 0.15 g of KCl.
5. 0.15 g of rose bengal.
6. 3 g of glucose.
7. 20 g of agar.
8. 950 mL of distilled water.