Photosynthetic carbon production and use by developing cotton leaves and bolls

Journal Article · · Crop Science; (USA)

DOI:https://doi.org/10.2135/cropsci1990.0011183X003000060021x· OSTI ID:6038520

Wullschleger, S D ^[1]; Oosterhuis, D M ^[2]

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1. Oak Ridge National Lab., TN (USA)
2. Univ. of Arkansas, Fayetteville (USA)

Understanding the photosynthetic C contribution of leaves to vegetative and reproductive processes is important in defining yield productivity. However, the morphological complexity of the cotton (gossypium hirsutum L.) canopy has proven a significant barrier to establishing specific yield relationships. Therefore, a 2-yr study examined the developmental sequences of C production and utilization by leaves and bolls within the crop canopy. Photosynthesis of sympodial leaves reached a maximum just prior to anthesis of the subtended flower and thereafter declined throughout the boll-filling period. Carbon budgets for individual sympodial leaves and their subtended bolls at mainstem Nodes 8, 10, and 12 indicated that C production was seldom synchronized with C utilization. Carbon import requirements for the first three fruiting positions at mainstem Node 10 were 50, 37, and 21%, respectively. Bolls at mainstem Node 8 collectively required >60% import of C to sustain growth during the season. Only at mainstem Node 12 were leaves capable of supplying the total C needs of their subtended bolls. Carbon deficiencies at mainstem Nodes 8 and 10 suggested that substantial translocation of photosynthate from adjacent leaves and leaves outside the mainstem node was necessary. This was confirmed through short-term studies of {sup 14}C-assimilate movement from leaves to developing cotton bolls. Breeding goals for improved C production by leaves were simulated to evaluate avenues for increased yields through crop genetics. These simulations indicated an advantage of increased leaf longevity in the maintenance of C production.

• OSTI ID: 6038520
• Journal Information: Crop Science; (USA), Journal Name: Crop Science; (USA) Vol. 30:6; ISSN 0011-183X; ISSN CRPSA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
CARBON
CARBON 14 COMPOUNDS
CARBON CYCLE
CHEMICAL REACTIONS
COTTON
COTTON PLANTS
ELEMENTS
GROWTH
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LEAVES
MAGNOLIOPHYTA
MAGNOLIOPSIDA
METABOLISM
NONMETALS
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PLANT GROWTH
PLANTS
SYNTHESIS
TRACER TECHNIQUES