الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
SUMMARY
Biological control became a vital tool for plant pests and diseases control, which depends heavily on chemical control using synthetic pesticides and has led to increasing issues and threats to the global health and the environment. Therefore, biopesticides will play an important role in integrated pest and disease management (IPDM).
The present work was conducted to study the mode of action and effectiveness of one of the most promising novel bio fungicides (fungal-based / Trichoderma-based bio fungicide) against key plant pathogens and certain fungal crop diseases through lab and field assays under local conditions.
The results could be summarized as follows:
1- The lab (in vitro) evaluation of commercial formulation of T34 Biocontrol ® (Trichoderma asperellum strain, T34) against twenty-six fungal isolates was performed by growing on Trichoderma asperellum- mixed PDA medium plates, where Trichoderma asperellum strain, T34 showed good antagonistic activities and significantly reduced/inhibited the fungal growth of all fungal pathogens tested strongly and such inhibiting effect was similar to Pink-S 30% SL (Hymexazol) fungicide (significantly inhibited). Most of the tested fungal isolates couldn’t grow on T34-inoculated PDA media Petri plates, while some grew for a few millimeters only.
2- Evaluation of T34 Biocontrol ® (Trichoderma asperellum strain, T34) using Dual-culture PDA plates technique showed that T34 Biocontrol has a good antagonistic and/or antibiosis activity against thirty-three tested fungal isolates, stopping its growth and overgrew a lot of isolates even. T34 Biocontrol significantly inhibited the growth of all fungal isolates tested. S. sclerotiorum (Green bean isolate) was the least effected pathogen due to its speed/rapid growth with 46.84% of growth inhibition only. While Rhizoctonia solani (Strawberry isolate) was the most inhibited with 93.75% of fungal growth inhibition.
3- Pink-S 30% SL (Hymexazol) synthetic chemical fungicide recommended for soil-borne fungal plant pathogens used as a positive control. The fungicidal effect of hymexazol was evaluated against ten different fungal isolates by linear (radial) growth on poisoned PDA media plates. Inhibiting concentration of 50% (IC50) values were 7.943, 91.201, 2.291, 57.54, 181.97, 181.97, 15.85, 7.943, 4.786 and 181.97 ppm on Alternaria solani, Aspergillus niger, Botrytis cinerea, Macrophomina phaseolina, Penicillium spp., Phytophthora nicotiones, Rhizoctonia solani, Sclerotium rolfsii, Sclerotina sclerotiorum and Verticilium alboatrum, respectively. Among the tested isolates, Alternaria solani, Botrytis cinerea and Sclerotium rolfsii were more susceptible to Pink-S 30% SL (Hymexazol).
4- Dual-culture test on slides clarified more than one antagonistic behavior of T. asperellum against fungal isolates tested. Attachment, coiling, penetration, and hyphal malformation/lysis (collapse) were clearly observed. M. phaseolina and R. solani were more susceptible to be parasitized by T34.
5- The separation of chemical substances of partially purified culture filtrate of T. asperellum by GC-MS clarified that different chemical substances with generally good/desired properties of antimicrobial, antibacterial, bactericidal, antifungal, antioxidant, anti-inflammatory, local anesthetic, antinociceptive, cicatrizing, antiseptic or anticancer properties can be produced by the tested biocontrol agent T34 and plays as antibiotics inhibiting the growth of plant pathogens. Of which substances volatile ones like: 9-octadecenoic acid (Z)- and anthrone, and non-volatile substances like: thymol, glycerol, 1-hexadecanol, 2-methyl-, d-mannitol, palmitic acid, oleic acid, stearic acid and 1-monopalmitin can be detected post one-week of the incubation period. While volatile substances like acetic acid, hydrazide, citronellene, carveol 1, linalool and stanozolol, and non-volatile compounds like thymol, glycerol, palmitic acid, oleic acid, stearic acid, arachidonic acid and 1-monopalmitin can be found post two weeks of the incubation period.
6- Acremonium butyri, Alternaria tenuissima, Fusarium oxysporum, F. sporotrichioides, F. subglutinans, Mucor hiemalis, Rhizoctonia fragaria, R. solani and Trichothecium roseum were successfully isolated and identified and considered associated with (as causal complex of) strawberry fruit rot diseases.
7- In vivo assay of the biocontrol agent T34 Biocontrol ® (Trichoderma asperellum strain, T34) under open field conditions against strawberry fruit rot diseases, showed that the field application of T34 significantly reduced the disease (fruit rots) incidence preharvest (on the field) and disease (fruit rots) incidence and severity postharvest (during cooled storage) in both frequently tested winter seasons 2020-2021 and 2021-2022. T34 achieved highly efficient protective performance and led to a disease reduction percentage exceeding 90 % in some trials. The present results were nearly comparable with disease control achieved by comparative chemical/conventional fungicides of Fabolous 75% WP (Tebuconazole 12.5% (w/w)+Chlorothalonil 62.5%), Fabric 30% SC (Tebuconazole 15% (w/v)+Kresoxim-Methyl 15% (w/v), Fango 50% WG (Pyraclostrobin 50% (w/w), Klop 50% WP (Difenoconazole 6% (w/w)+Thiophanate methyl 44% (w/w), Maven 18.7% WG (Pyraclostrobin 6.7%(W/V)+Dimethomorph 12%(W/V) and Mystic 20% WP (Pyrimethanil 20% (w/w).
8- In the winter season of 2020-2021, T34 Biocontrol (in twice of recommended dose) was the best, followed by Mystic 20% WP and Fabric 30% SC, reducing disease (field fruit rot) incidence % by 82.86, 78.78 and 77.14%, respectively. Post-harvest Disease (Fruit rot) Severity % after 14-days refrigeration (cooled storage) was reduced numerically by 41.49% and 40.25% for Klopp 50 WP and T34 Biocontrol (in highest concentration tested), respectively.
9- In the winter season of 2021-2022 T34 Biocontrol was competitive to comparative synthetic fungicides in reducing fruit rot incidence percentage on field and also fruit rot incidence and fruit rot severity post-harvest (during cooled storage).
10- T34 Biocontrol (Trichoderma asperellum strain T34) field application can significantly reduce the incidence and severity of strawberry fruit rot diseases not only in the field (preharvest) but also postharvest during cooled storage (shelf life).
11- Post-harvest fungicidal treatment of banana fruits significantly reduced rot severity. T34 Biocontrol was the best, followed by Mystic 20% WP (Pyrimethanil), respectively. General Disease Severity % values were 60.67, 52, 47.22 and 49.11% for the Not washed, Washed, T34 and Mystic (Pyrimethanil) treated banana fruits. Not-washed fruits were more susceptible to be diseased/infected/rotten than washed ones. Aspergillus fumigatus, Fusarium sambucium, F. semitectum, F. subglutinans, Geotrichum candidum, Penicillium brevicompactum and Trichothecium roseum were successfully isolated and identified and considered as a causal complex of (associated with) banana fruit rots. Fungicidal treatment of banana fruits could reduce post-harvest fruit rots and extend fruits shelf-life.
12- Field evaluation of T34 Biocontrol against broad (faba) bean leaf spots proved that both T34 Biocontrol and Sand Cure 72WP (mancozeb 64% (w/w) + metalaxyl 8% (w/w)) spraying significantly reduced disease incidence percentage. Sand Cure was the best followed by T34 in highest dose tested (twice the recommended dose). Disease (Leaf spot) Incidence % values were 93, 75.4, 69, 63 and 55% for Control, T34 (half of recommended dose), T34 (recommended dose), T34 (twice of the recommended dose) and Sand Cure, respectively.