Trichoderma

mode of action of trichoderma, antibiotics produced and thus their role of in plant disease management

1. Safeena Majeed , A.A PALB 6132 et54y65udfdsgfdgf

2. Role of Trichoderma in plant disease management

3. Trichoderma spp. are present in nearly all agricultural soils. They are the most prevalent  culturable  fungi. Many species in this genus can be characterized as opportunistic avirulent plant symbionts . This refers to the ability of several Trichoderma  species to form mutualistic endophytic relationships with several plant species. The genomes of several Trichoderma  species have been sequenced.

4. Scientific Classification Kingdom: Fungi Division: Ascomycota Subdivision: Pezizomycotina Class: Sordariomycetes Order: Hypocreales Family: Hypocreaceae Genus: Trichoderma by Christiaan Hendrik Persoon in 1794

5. Antifungal abilities have been known since 1930s Mycoparasitism Nutrient competition Agriculturally used as biocontrol agent and as a plant growth promoter.

6. Uses antibiosis Predation against soil borne pathogens such as Pythium Rhizoctonia Fusarium Sclerotina

7. How the colony looks Cultures are fast growing at 25–30 °C, but some species at 45 °C. Media: CMD or PDA. Mycelium are not typically obvious on CMD.  Conidia typically form within one week in compact or loose tufts.

8. Will be in shades of green or yellow or less frequently white. A yellow pigment may be secreted into the agar, especially on PDA. Few species produce characteristic sweet or 'coconut' odour. Conidiophores are highly branched and thus difficult to define or measure loosely or compactly tufted often formed in distinct concentric rings borne along the scant aerial hyphae .

9. Main branches produce lateral side branches that may be paired or not. The longest branches distant from the tip. All primary and secondary branches arise at or near 90° with respect to the main axis.

10. Conidia typically appear dry. Some species they held in drops of clear green or yellow liquid (e.g.  T. virens ,  T. flavofuscum ). Conidia of most species are ellipsoidal: (L/W = > 1.3) globose conidia:(L/W < 1.3) are rare. 3–5 x 2–4 µm Conidia are typically smooth but few species with tuberculate to finely warted conidia.

11. Occurence Frequently isolated from forest or agricultural soils at all latitudes Hypocrea  species are most frequently found on bark or on decorticated wood. Many species grow on bracket fungi e.g.  H. Pulvinata Bird's nest fungi - H. Latizonata Agarics - H. avellanea .

12. Trichoderma isolates Code Isolation source T. koningii TK Ismailia governorate T. hamatum1 TM1 Menoufia governorate T. hamatum2 TM2 Menoufia governorate T. hamatum3 TM3 Gharbia governorate T. hamatum4 TM4 Sharkya governorate T. viride 1 TV1 Gharbia governorate T. viride 2 TV2 Kafer El- shikh governorate T. viride 3 TV3 Sharkya governorate T. viride 4 TV4 Menoufia governorate T. harzianum 1 TZ1 Sharkya governorate T. harzianum 2 TZ2 Ismailia governorate T. harizianum 3 TZ3 Menoufia governorate   Isolation a/c Elad (1981) identification a/c Barnett (1998) and Bissett ( 1991 )   Isolation and identification of Trichoderma isolates

13. Genetic Modification Wild strains Heterokaryotic – contain nuclei of dissimilar genotypes within a single organism Biocontrol strains Homokaryotic – contain nuclei which are similar or identical Allows genetic distinction and non-variability IMPORTANT FOR QUALITY CONTROL Why buy/develop a product that is readily available in the soil?

14. Most strains have innate resistance to some agricultural chemicals Resistance is variable Strains available for commercial use are selected or modified for resistance to specific chemicals

15. Mode of action Trichoderma spp. attach to the host hyphae via coiling, hooks and appressorium like bodies. Penetrate the host cell wall by secreting lytic enzymes. Trichoderma recognizes signals from the host fungus, triggering coiling and host penetration .

16. Some strains colonize the root with mycoparasitic properties Penetrate the root tissue Induce metabolic changes which induce resistance Accumulation of antimicrobial compounds A biomimetic system consisting of lectin -coated nylon fibers was used to study the role of lectins in mycoparasitism . Using this system we could also identify specific coiling-inducing molecules.

17. Attachment to the host hyphae by coiling Lectin -carbohydrate interaction (Hubbard et al., 1983. Phytopathology 73:655-659).

18. Mycoparasitism of Rhizoctonia solani by Trichoderma virens : A, parent strain coiling around host hyphae , and B, mycoparasitic -deficient mutant with no coiling or penetration of host hyphae .

19. 2. Penetrate the host cell walls by secreting lytic enzymes Chitinases Proteases Glucanases ( Ilan Chet, Hebrew University of Jerusalem).

20. Antibiotics produced Trichodermin Dermadin Trichoviridin Sesquiterpenes Trichozianines Isonitriles Pentyl analogues Gliotoxin Gliovirin

21. Growth inhibition of Pythium ultimum by the Trichoderma virens – produced antibiotic gliovirin : A, parent strain, and B, gliovirin -deficient mutant .

22. Growth inhibition of Rhizoctonia solani by the Trichoderma virens – produced antibiotic gliotoxin : A, gliotoxin -amended medium, and B, nonamended medium.

23. a. Pythium aphanidermatum b. Rhizoctonia Solani c. Trichoderma against Pythium aphanidermatum d. Trichoderma against Rhizoctonia Solani Inhibition of P. aphanidermatum and R. solani growth in presence of Trichoderma

24. • Control of root and foliar pathogens Induced resistance. Biological control of diseases by direct attack of plant pathogenic fungi. Mycoparasitism Antibiosis Competition for nutrients or space • Changes in the microfloral composition on roots. . Role in plants

25. • Enhanced nutrient uptake. • Enhanced solubilization of soil nutrients. • Enhanced root development. • Increased root hair formation • Tolerance to stress through enhanced root and plant development • Solubilization of inorganic nutrients • Induced resistance • Inactivation of the pathogen’s enzymes

26. Effect OF Trichoderma viride on Tomato Damping off disease Treated Untreated

27. EFFECT OF TRICHODERMA VIRIDE ON ROOT ROT DISEASE OF COTTON Treated Untreated

28. TRICHODERMA VIRIDE vs COWPEA ROOT ROT Treated Untreated

29. Inoculate Trichoderma in the rootstock and the graft. The uniqueness of the process is that the rootstock and the scion are both inoculated during process.

30. T-22 Commercial available Trichoderma formulation. Used as seed coating material. Protects roots from diseases caused by Pythium , Rhizoctonia and Fusarium . Interacts with the Rhizosphere , near the root hairs and increases the available form of nutrients needed by plants.

31. Commercial formulations Product Antagonist Target Pathogen Source Binab-T Trichoderma spp Endothia parasitica Armillaria me/tea Ceratocystfs ulmi Sweden Trichodermin Trichoderma spp Botrytis cinerea Pythium spp. Sclerotinia Sclerotiarum Verticillium Bulgaria & Russia F-Stop T. harzianum Pythium spp. U.S.A. Trichodex T. harzianum Erysiphe spp. Uncinula necator Israel

32. Commercial products

33. Applications Bio control agent. Medical use: Cyclosporine A, an immunosuppressant in organ transplants to prevent rejection. Industrial uses: enzyme production- Trichoderma reesei  - cellulase  and hemicellulase   Trichoderma longibrachiatum  - xylanase Trichoderma harzianum  - chitinase

34. Conclusion Transgenes Biocontrol microbes contain a large number of genes which allow biocontrol to occur Cloned several genes from Trichoderma as transgenes Produce crops which are resistant to plant diseases Currently not commercially available The isolates of T. harizianum and T. viride were the most active against R.Solani and P . aphnidermatum