title: Alterations in osmoregulation, antioxidant enzymes and indole alkaloid levels in Catharanthus roseus exposed to water deficit.
abstract: Catharanthus roseus (L.) G. Don plants were grown in different water regimes in order to study the drought induced osmotic stress and proline (PRO) metabolism, antioxidative enzyme activities and indole alkaloid accumulation. The plants under pot culture were subjected to 10, 15 and 20 days interval drought (DID) stress from 30 days after sowing (DAS) and regular irrigation was kept as control. The plants were uprooted on 41DAS (10DID), 46DAS (15DID) and 51DAS (20DID). The drought stressed plants showed increased aminoacid (AA), glycine betaine (GB) and PRO contents and decreased proline oxidase (PROX) and increased gamma-glutamyl kinase (gamma-GK) activities when compared to control. The antioxidative enzymes like peroxidase (POX) and polyphenol oxidase (PPO) increased to a significant level in drought stressed plants when compared to control. The drought stressed C. roseus plants showed an increase in total indole alkaloid content in shoots and roots when compared to well-watered control plants. Our results suggest that the cultivation of medicinal plants like C. roseus in water deficit areas would increase its PRO metabolism, osmoregulation, defense system and the level of active principles.
authors.affiliation: Stress Physiology Lab, Department of Botany, Annamalai University, Annamalainagar 608002, Tamilnadu, India. abdul79jaleel@rediffmail.com
authors.forename: C Abdul
authors.initials: CA
authors.lastname: Jaleel
authors.forename: P
authors.initials: P
authors.lastname: Manivannan
authors.forename: A
authors.initials: A
authors.lastname: Kishorekumar
authors.forename: B
authors.initials: B
authors.lastname: Sankar
authors.forename: R
authors.initials: R
authors.lastname: Gopi
authors.forename: R
authors.initials: R
authors.lastname: Somasundaram
authors.forename: R
authors.initials: R
authors.lastname: Panneerselvam
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D030008:Catharanthus / Q000201:enzymology* / Q000378:metabolism; D003681:Dehydration / Q000378:metabolism; D026121:Indole Alkaloids / Q000378:metabolism*; D009995:Osmosis / Q000502:physiology; D014867:Water / Q000378:metabolism; D014882:Water-Electrolyte Balance / Q000502:physiology*
chemical_list: D000975:Antioxidants; D026121:Indole Alkaloids; D014867:Water