Title Physiological reaction and chemical composition of Stachys schtschegleevii Sosn. essential oil under water deficit. Type of Research Article Keywords α-campholenal, dry matter, growth, drought stress, medicinal plants Abstract α-campholenal, dry matter, growth, drought stress, medicinal plants Researchers Hamid Mohammadi (First Researcher)، Ahmad Aghaee (Second Researcher)، (Third Researcher)، Mansour Ghorbanpour (Fourth Researcher)، Saeid Hazrati (Fifth Researcher)