Abscisic acid biosynthesis in water-stressed leaves

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6555341

Li, Yi

Although abscisic acid (ABA) was discovered 30 years ago, very little is known about its biosynthetic pathway in higher plants. Two hypotheses have been proposed: (i) a direct pathway involving only C-15 intermediates like farnesyl pyrophosphate, (ii) an indirect pathway involving C-40 intermediates like the xanthophylls. When {sup 14}CO{sub 2} was fed into greened bean plants, the {sup 14}C specific activity of ABA was always lower than those in xanthophylls, such as violaxanthin and lutein, regardless of {sup 12}CO{sub 2} chase periods. The ABA accumulation in green leaves was not affected by fluridone when plants were stressed once, but the {sup 14}C incorporation into ABA was inhibited to the same extent as those of xanthophylls. The incorporation of {sup 18}O into the ABA ring when violaxanthin was labeled by {sup 18}O in vivo via the violaxanthin cycle indicates that at least a portion of ABA was derived from {sup 18}O-labeled violaxanthin during water stress.

• Research Organization: State Univ. of New York, Syracuse, NY (USA). Coll. of Environmental Science and Forestry
• OSTI ID: 6555341
• Country of Publication: United States
• Language: English

Related Subjects

550201 -- Biochemistry-- Tracer Techniques
550501* -- Metabolism-- Tracer Techniques
551001 -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ABSCISIC ACID
AUXINS
BIOLOGICAL ACCUMULATION
BIOLOGICAL PATHWAYS
BIOLOGICAL STRESS
BIOSYNTHESIS
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
EVEN-EVEN NUCLEI
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LEAVES
LEGUMINOSAE
LIGHT NUCLEI
MAGNOLIOPHYTA
MAGNOLIOPSIDA
MONOCARBOXYLIC ACIDS
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXYGEN 18
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
PHASEOLUS
PLANT GROWTH REGULATORS
PLANTS
STABLE ISOTOPES
SYNTHESIS
TRACER TECHNIQUES
WATER