Table 3: Metabolites and hormones involved in plant responses to stress.

StressReference

Abscisic acid, jasmonic acid, salicylic acid, polyamines, and othersDrought, salinity, cold[3, 58, 6567]
Proline, glycine-betaine, and other compatible osmolytesEnvironmental stresses: drought, salinity, osmotic[6264]
PhytoalexinsMicrobial pathogens[89]
TerpenesToxins and pathogens[89]
Phenolic compounds (coumarin, lignin, flavonoids, tannins, isoflavonoids)Pathogens, oxidative stress, UV light[89, 90]
AlkaloidsPathogens (predators)[87]
Unsaturated fatty acidsEnvironmental stresses[73]
ROS, malondialdehydeBiotic and abiotic stresses[3, 58, 68]
Phytochelatins and metallothioneinsHeavy metal intoxication[76, 77]