The effect of plant regulators on the concentration of carotenoids and phenolic compounds in foliage of coriander.

Foliage of coriander crop is a rich source of pro-vitamin-A carotenoids and phenolics of relevance to
human health. Foliar-application of plant growth regulators e methyl jasmonate and salicylic acid,
differentially elicited total carotenoids, b-carotene, lutein, chlorophylls, total phenolics and chlorogenic
acid in coriander, GS4 Multicut and Mahak, the cultivars with high and low carotenoids respectively.
Carotenoids and total phenolics increased 6.8 and 3 folds respectively when treated with methyl
jasmonate (10 mmol/L), whereas salicylic acid (500 mmol/L) showed 5.4 and 3.5 folds of respective
compounds. These treatments also enhanced levels of b-carotene, lutein, chlorophylls and chlorogenic
acid, as observed by HPLC/MS analyses. Carotenoid and phenolic extracts of the best treatments showed
significant increase in hydroxyl and superoxide radical scavenging antioxidant activities compared with
controls. The observations made here indicate that the precise use of plant growth regulators is a simple
method for naturally augmenting the nutritionally important compounds in coriander crop.