Lignin: Characterization of a Multifaceted Crop Component

Table 1

Effect of abiotic stresses on lignin concentration of different morphological fractions of crops.

Species/morphological fraction	Effect on lignin	References
Drought
Forage legumes	↓↑	[48–52]
Forage grasses	↓↑—	[53–55]
Maize leaves, Zea mays L.	↓↑—	[56, 57]
Barley straw, Hordeum vulgare L.	↑	[58]
Salinity
Lettuce roots, Lactuca sativa L.	↑	[59]
Tomato roots, Solanum lycopersicon L.	↑—	[60, 61]
Bean roots, Phaseolus vulgaris L.	↑	[62]
Maize roots, Zea mays L.	↑	[63]
Rice root, Oryza sativa L.	↓↑	[64, 65]
Soybean root, Glycine max L.	↑	[66]
Mineral toxicities (Al, B, Cd, Cu, Mn)
Chamomile root, Matricaria chamomilla L.	↓↑—	[67]
Rice roots	↑	[68]
Wheat roots, Triticum aestivum L.	↑	[69, 70]
Flax roots, Linum usitatissimum L	↑	[71]
Soybean roots	↑	[72, 73]
Tomato roots	↑	[74]
Mineral deficiencies (Ca, K, Mn, N, P, Si)
Wheat root and shoot	↓	[75, 76]
Chamomile root	↑	[77]
Tobacco root/shoot, Nicotiana tabacum L.	↑	[78]
Soybean root	↑	[79]
Potato tubers, Solanum tuberosum L.	↑	[80]
Rice shoot	↑	[81]
Ozone
Rice straw	↑	[32, 34, 82]
Forage legumes	↑	[83, 84]
Forage grasses	↑	[85–87]
UV
Forage grasses	↑	[88]
Tomato fruit	↑	[89]
Cucumber seedlings, Cucumis sativus L.	↑	[90]
Quinoa seedlings; Chenopodium quinoa Willd.	↑	[91]
Soybean leaves	↓	[92]

↑ indicates that exposure to stress induced an increase in lignin content, ↓ indicates that exposure to stress induced a decrease in lignin content; — indicates that exposure to stress had no clear effect on lignin content.