Ameliorative effect of chlormequat chloride on water stressed cultivars of Japanese mint (Mentha arvensis)

A comparison of responses of five cultivars of Japanese mint (Mentha arvensis L. var. Piperascens Mal.) to water stress and chlormequat chloride application has brought out considerable intervarietal variation. Relative water content, water potential, herbage and oil yield decreased under water stress, while abscisic acid, sugar content, peroxidase activity, oil and menthol content increased significantly. Ameliorative effect of chlormequat chloride was observed in stressed plants of different varieties. RWC, herbage and oil concentration increased and ABA and peroxidase activity decreased in chlormequat chloride treated stressed plants, as compared with untreated stressed plants. Observations suggest that chlormequat chloride can partially alleviate the detrimental effect of water stress in Japanese mint.