Photoassimilate partitioning of main shoot leaves in field-grown spring barley. [Hordeum vulgare L]

Journal Article · · Crop Sci.; (United States)

OSTI ID:6035208

Lauer, J G; Simmons, S R

Premature tiller mortality could conceivably limit grain yield production in barley (Hordeum vulgare L.). Knowing photoassimilate partitioning patterns during the vegetative development phase of growth is important for understanding the causes of tiller mortality. A field experiment was conducted to ascertain the /sup 14/C translocation patterns of individual main shoot leaf blades during the pre-anthesis period for three spring barley genotypes differing in tiller production and survival. One of the top three to five leaves was labelled with /sup 14/CO/sub 2/ on each date and above ground plant parts were harvested for determining the distribution of /sup 14/C after a 24 h translocation period. Also, for two of the leaves, labelled plants were allowed to translocate until anthesis or maturity before the distribution of radioactivity was measured. Most /sup 14/C fixed by the first developed leaves on the main shoot was translocated to newly emerging main shoot leaves or to young tillers. The leaf subtending and the leaf above a particular tiller preferentially exported carbon to that tiller. During the early tiller production phase of growth, proportionately more /sup 14/C was translocated to tiller of the higher tillering genotypes than for the lower tillering one. During the time when tiller mortality became evident, no differences in partitioning patterns were found between the high or low tiller mortality genotypes. Later formed leaves in all genotypes provided relatively large proportions of labelled photoassimilate to the main shoot stem and inflorescence. A sharp decline in the percentage of /sup 14/C translocated to all tillers occurred when the main stem began rapid growth. The authors conclude that the shift in main shoot photoassimilate translocation away from tillers and to the main shoot stem contributes to the premature abortion of tillers in barley.

• Research Organization: Univ. of Minnesota, St. Paul
• OSTI ID: 6035208
• Journal Information: Crop Sci.; (United States), Journal Name: Crop Sci.; (United States) Vol. 25:5; ISSN CRPSA
• Country of Publication: United States
• Language: English

Related Subjects

553001* -- Agriculture & Food Technology-- Tracer Techniques-- (-1987)
60 APPLIED LIFE SCIENCES
BARLEY
CARBON 14 COMPOUNDS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CEREALS
CHALCOGENIDES
CHEMICAL REACTIONS
GRASS
GROWTH
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LEAVES
METABOLISM
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PLANT GROWTH
PLANTS
SYNTHESIS
TRACER TECHNIQUES
TRANSLOCATION