Partitioning of sup 14 C-photosynthate and biomass in relation to senescence characteristics of sorghum. [Sorghum bicolor (L. ) Moench]

Journal Article · · Crop Science; (USA)

OSTI ID:6977750

Vietor, D M; Cralle, H T; Miller, F R ^[1]

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1. Texas A and M Univ., College Station (USA)

The stems remaining after harvest of sorghum (Sorghum bicolor (L.) Moench) grain are a low-cost source of biomass. Semidwarf hybrids exhibiting nonsenescent characteristics may yield more stem biomass than senescent hybrids. This study compared a nonsenescent to a senescent hybrid of semidwarf sorghum using dry wt. and partitioning of {sup 14}C-photosynthate and {sup 14}C-starch at three stages. A leaf was exposed to {sup 14}CO{sub 2} or {sup 14}C-starch was injected into the middle internode of each hybrid during grain filling and at or after (post) black layer of the grain. Although dry wt. of stem internodes were significantly greater for the nonsenescent compared to the senescent hybrid, {sup 14}C-photosynthate partitioning among parts did not differ between hybrids after chase periods of 5 or 7 d. Patterns of {sup 14}C-photosynthate partitioning indicated grain, stem internodes, and lateral branches were dominant sinks at grain filling, black layer, and post black layer, respectively. Lateral branch growth comprised all of the biomass increase from black layer to post black layer. At post black layer, 47% of assimilated {sup 14}CO{sub 2} was partitioned to lateral branches. Both {sup 14}C-photosynthate and {sup 14}C-starch were remobilized from stem internodes to lateral branches of both hybrids after black layer. Although unmeasured in previous comparisons between nonsenescent and senescent sorghum hybrids, lateral branch growth limited storage of {sup 14}C-photosynthate in stem internodes and resulted in similar patterns of {sup 14}C-photosynthate partitioning for the two hybrids after black layer in this study.

• OSTI ID: 6977750
• Journal Information: Crop Science; (USA), Journal Name: Crop Science; (USA) Vol. 29:4; ISSN 0011-183X; ISSN CRPSA
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
090700* -- Biomass Fuels-- Resources-- (1990-)
551001 -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
BIOMASS
CARBON 14 COMPOUNDS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CEREALS
CHALCOGENIDES
CHEMICAL REACTIONS
ENERGY SOURCES
GRASS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LILIOPSIDA
MAGNOLIOPHYTA
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PHYSIOLOGY
PLANTS
RENEWABLE ENERGY SOURCES
RESOURCE POTENTIAL
SORGHUM
SYNTHESIS
TRACER TECHNIQUES