Document Type : Original Article
Authors
1
Veg. Dis. Res. Dept., Pl. Pathol. Res. Inst., ARC, Giza, Egypt
2
Veg. Dis. Res. Dept., Plant Pathol. Res. Inst., ARC, Giza, Egypt
Abstract
Cucumber (Cucumis sativus L.) plants are liable to infect by many fungal pathogens. However, powdery mildew caused by Erysiphe cichoracearum and Sphaerotheca fuliginea, is a very damaging. Foliar application of cucumber plants cv. Beit Alpha with the fungicide thiophanate - methyl (Topsin 70% WP) as a comparison treatment, potassium silicate (5 m/l), dry yeast (4000 mg/l) and ascorbic acid (100 mg/l), significantly reduced disease severity by 86.00, 68.31, 50.86 and 42.03%, respectively compared with the untreated plants in 2013 season. The same trend was found in 2014 season (86.02, 71.33, 48.06 and 45.27%), respectively. Moreover, the aforementioned treatments significantly increased each of plant height/plant, number of leaves/plant, dry weight/plant and number of flowers as well as yield components (number of fruits/plant and mean of fruits weight/plant). Also, the treatments increased peroxidase activity and total phenolic content. Reduction in disease severity was positively correlated with both of peroxidase activity (R2 = 56.3, P ˂ 0.005) and total phenolic content (R2 = 77.2, P ˂ 0.005). Foliar application with potassium silicate, dry yeast and ascorbic acid at the rate of 5ml, 4000 mg and 100 mg/l induced new pathogenesis related proteins (PR-protein) with various molecular weights in the shoots of cucumber plants upon natural infection with the powdery mildew pathogen. Furthermore, these treatments resulted in a significant increase of N, P, K contents of vegetative shoots.
Keywords
)
View on SCiNiTO