Copper complexes of the 1,3,4-thiadiazole derivatives modulate antioxidant defense responses and resistance in tomato plants against fungal and bacterial diseases.
The metallic complexes μ-chloro-μ-[2,5-bis (2-pyridyl)-1,3,4-thiadiazole] aqua chlorocopper (II) dichlorocopper (II) (abbreviated 2PTH-Cu2-Cl4); aquabis [2,5-bis (2-pyridyl)-1,3,4-thiadiazole-κ2N2,N3] (trifluoromethane-sulfonato-κO) copper(II) trifluoro metrhanesulfonate (2PTH-Cu-tF) and bis[(2,5-bis(pyridine-2-yl)-1,3,4-thiadiazole-di-azido copper(II)] (2PTH-Cu-Az) were compared for their antimicrobial activities in vitro, and their aptitude to control Verticillium wilt and crown gall diseases development of tomato in the greenhouse. Results showed that the complex 2PTH-Cu-Az inhibited drastically the growth of V. dahliae in vitro. 2PTH-Cu2-Cl4 and 2PTH-Cu-tF did not display any noticeable antimicrobial activity in vitro against all of the pathogens tested. However, in planta evaluation revealed that the three complexes protected tomato against crown gall similarly. They also reduced Verticillium wilt disease severity, although the complex 2PTH-Cu-Az was the most efficient. When compared to other complexes, 2PTH-Cu-Az triggered only a weak oxidative burst as revealed by H2O2 measurement and the activity of ascorbate peroxidase and catalase. These results suggest that the superiority of 2PTH-Cu-Az against V. dahliae rely on its direct antifungal activity and its ability to modulate H2O2 accumulation.
['Smaili|Amal|A|', 'Rifai|Lalla Aicha|LA|', 'Esserti|Siham|S|', 'Koussa|Tayeb|T|', 'Bentiss|Fouad|F|', 'Guesmi|Salaheddine|S|', 'Laachir|Abdelhakim|A|', 'Faize|Mohamed|M|']
D016960:Agrobacterium tumefaciens D000935:Antifungal Agents D060387:Ascorbate Peroxidases D002374:Catalase D003300:Copper D044084:Erwinia amylovora D006861:Hydrogen Peroxide D018551:Lycopersicon esculentum D010935:Plant Diseases D044224:Pseudomonas syringae D013830:Thiadiazoles D020172:Verticillium
Copper complexes Tomato Verticillium wilt Crown gall, active oxygen species, antioxidant defenses