Abstract
Fungicides using for an effective control of plant diseases have become crucial in the last decades in the agricultural system. The efficiency of seed dressing fungicides in controlling damping off caused by Rhizoctonia solani under greenhouse conditions and its effect on plant growth and metabolism of cotton plant seeds was studied by treatment with systemic and contact fungicides. The results showed that Monceren showed the highest efficiency (72%) while each of Montoro and Sumi-8 showed the lowest efficiency (48% and 36 % respectively) in controlling damping off. Significant decrease in plant height, dry weight of plant, phytohormones, photosynthetic pigments, soluble sugars, soluble proteins, total free amino acids, polyphenol oxidase caused by Bastin fungicide, but caused significant increases in total phenols, flavonoids, antioxidant enzymes, reduced glutathione, lipid peroxidation and hydrogen peroxide as compared with untreated plants. On the other hand, Topsim and Monceren fungicides increased all the above recorded parameters except phenols, MDA and H2O2 as compared with untreated plants. Our results indicated that Topsim Monceren and Premis fungicides can be used as growth regulators and decreased plant diseases.