Table 2.

The role of defense-related enzymes regulated by silicon in biotic stress

Stress/disease	Plant	Antioxidants	Source
Anthracnose	Bean (Phaseolus vulgaris)	SOD, APX and GR	[141]
Powdery mildew, crown and root rot	Cucumber (Cucumis sativus)	POD, PPOs, CHT and POD	[37, 50]
Powdery mildew and pink rot	Melon (Cucumis melo)	POD, CHT, SOD, and β-1,3-glucanase	[149, 152]
Leaf spot	Pea (Pisum sativum)	CHT and β-1,3-glucanase	[155]
Blast, brown spot, sheath blight	Rice (Oryza sativa)	Glucanase, POD, PPOs, phenylalanine ammonia-lyase, SOD, CAT, APX, GR, lipoxygenase, Phenylalanine ammonia-lyases, CHT and β-1,3 glucanase	[51, 67, 116, 120, 163, 164]
Target spot	Soybean (Glycine max)	CHT, β-1-3-glucanases, phenylalanine ammonia-lyases, POD and PPOs	[165]
Blast	Wheat (Triticum spp.)	CHT and POD	[162]
Bacterial wilt and blight	Tomato (Solanum lycopersicum)	CAT, APX, SOD, GR POD and phenylalanine ammonia lyase	[72, 166]