See:
Title: Restoration of seed germination at supraoptimal temperatures by fluridone, an inhibitor of abscisic acid biosynthesis.
Authors: Yoshioka, Toshihito; Endo, Takashi; Satoh, Shigeru.
Authors affiliation: Laboratory of Bio-adaptation, Graduate School of Agriculture, Tohoku University, Sendai, Japan.
Published in: Plant and Cell Physiology (1998), 39(3), pages 307-312.
Abstract: "Fluridone, an inhibitor of ABA biosynthesis, restored the seed germination of lettuce (Lactuca sativa L. cv. Grand Rapids) and many other plant species at supraoptimal temps. ABA content in lettuce seeds after imbibition quickly decreased at 23
See:
Link: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15060827&dopt=Abstract
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Title: Dormancy of yellow cedar seeds is terminated by gibberellic acid in combination with fluridone or with osmotic priming and moist chilling
Authors: SCHMITZ N. (1) ; XIA J.-H. (2) ; KERMODE A. R. (1)
Authors affiliations:
(1) Department of Biological Sciences, Simon Fraser University, Burnaby, B.C., V5A 1S6, CANADA
(2) Woodmere Nursery, P.O. Box 195, Telkwa, B.C., V0J 2X0, CANADA
Published in: Seed science and technology, volumn 29, p 331-346, (2001)
Abstract: “Following dispersal from the parent tree, seeds of yellow cedar (Chamaecyparis nootkatensis D. Don Spach) exhibit a low capacity for germination, primarily as a result of coat-imposed dormancy. Combined warm and cold stratification (generally 4 weeks and 8 weeks, respectively) is often used to break dormancy. Here we investigate the effectiveness of different chemical treatments in replacing warm stratification and in reducing the requirement for cold stratification (moist chilling). Treatments comprised of gibberellic acid (GA3) in combination with osmotic priming (using polyethylene glycol, PEG) or with other hormones (gibberellin[4+7] and benzylaminopurine) had a promotive effect on subsequent germination of whole seeds of yellow cedar after a 60-day moist chilling period. GA[3] had virtually no effect on germination when used alone and even when used with 60 days of moist chilling. Whole seeds exposed to GA[3] and to fluridone (the latter to diminish endogenous abscisic acid, ABA), exhibited increased germination with an increasing time of exposure to fluridone, even in the complete absence of moist chilling, but seedlings were abnormal and unable to survive. Embryos excised from mature seeds which had been subjected to dormancy-breaking treatments (osmotic priming, GA[3], and moist chilling), exhibited a lowered sensitivity to ABA compared to embryos excised from mature seeds that had received only a 3-day water soak. A decline in ABA within the seed and/or reduced embryo sensitivity to ABA may be two critical factors leading to dormancy breakage of yellow cedar seed.”