4-CHLOROINDOLE-3-ACETIC AND INDOLE-3-ACETIC ACIDS IN PISUM-SATIVUM

Endogenous IAA and 4-chloroindole-3-acetic acid (4-Cl-IAA) were analys ed in vegetative and reproductive tissues of the garden pea (Pisum sat ivum) using GC-MS selected ion monitoring in the presence of stable-is otope labelled internal standards. In fruit collected 3-8 days after a nthesis (DAA) conjugates of both auxins were more abundant than the fr ee hormones. Auxin levels (ng g(-1) fr. wt) in the seeds were higher b y 1-2 orders of magnitude than in the pericarps. However, as seeds are small at this stage, the pericarp nevertheless contains a substantial fraction of the overall quantity of IAA and 4-Cl-IAA. While, in young fruit tissues, IAA was more abundant than 4-Cl-IAA, the opposite was true for seeds at the 'table-ready' stage and for roots of nine-day-ol d seedlings. Our data suggest that both IAA and 4-Cl-IAA are required to coordinate the vegetative and reproductive growth of pea plants. (C ) 1997 Elsevier Science Ltd.