A kinetic and microautoradiographic study of sup 14 C-sucrose translocation into developing wheat grains

Conference · Wed May 01 00:00:00 EDT 1991 · Plant Physiology, Supplement; (United States)

OSTI ID:5640341

Wang, Ning; Fisher, D B ^[1]

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1. Washington State Univ., Pullman (United States)

The kinetics of {sup 14}C-photosynthate import by developing wheat grains was followed after pulse-labeling the flag leaf with {sup 14}CO{sub 2}. Samples were collected from four successive points along the transport pathway to and within the grain: exuding aphid stylets on the peduncle, exuding grain pedicels, the grain crease tissues, and the liquid contents of the endosperm cavity. In addition, microautoradiographs were prepared of the grain crease tissues during movement of the {sup 14}C pulse into the grain. At all times, sucrose accounted for 93 to 97% of the total {sup 14}C present at all four sampling sites. The main features of the {sup 14}C kinetics could be accounted for by a simple compartmental model consisting of sucrose pools in series. Microautoradiographs of the crease tissues showed fairly uniform labeling of vascular parenchyma at all times, with a sharp gradient in labeling across the chalaza to the nucellus. Thus the principal resistance to post-phloem solute transport through the maternal tissues appears to be in the symplastic pathway across the chalaza.

• OSTI ID: 5640341
• Report Number(s): CONF-9107184-; CODEN: PPYSA
• Journal Information: Plant Physiology, Supplement; (United States), Vol. 96:1; Conference: Annual meeting of the American Society of Plant Physiology, Albuquerque, NM (United States), 28 Jul - 1 Aug 1991; ISSN 0079-2241
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
SACCHAROSE
METABOLISM
WHEAT
PHYSIOLOGY
AUTORADIOGRAPHY
BIOLOGICAL PATHWAYS
CARBON 14 COMPOUNDS
CARBON DIOXIDE
LEAVES
PHOTOSYNTHESIS
TRANSLOCATION
CARBOHYDRATES
CARBON COMPOUNDS
CARBON OXIDES
CEREALS
CHALCOGENIDES
CHEMICAL REACTIONS
DISACCHARIDES
GRAMINEAE
LABELLED COMPOUNDS
LILIOPSIDA
MAGNOLIOPHYTA
OLIGOSACCHARIDES
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PLANTS
SACCHARIDES
SYNTHESIS
550501* - Metabolism- Tracer Techniques