Energy Relations and Carbohydrate Partitioning in Turfgrasses

2015 ◽  
pp. 175-205
Author(s):  
Richard J. Hull
Keyword(s):  
Carbohydrate Partitioning ◽  
Energy Relations

CNDO/2 study of interaction of 1-methyl-1,4-dihydronicotinamide and acetaldehyde

1981 ◽  
Vol 46 (3) ◽  
pp. 740-747 ◽  
Author(s):  
Jiří Krechl ◽  
Josef Kuthan
Keyword(s):  
Electron Distributions ◽  
Stabilization Energies ◽  
Energy Relations ◽  
Favourable Situation

The CNDO/2 method has been used for evaluation of energy relations between some configurations of 1-methyl-1,4-dihydronicotinamide (I) - acetaldehyde (II) supermolecule. Stabilization energies have been estimated for formation of the configuration type A,B and C, the energetically most favourable situation corresponding to the formulas IIIa and IIIb. Characters of some MO's and CNDO/2 and INDO electron distributions are discussed with respect to biochemical aspects of the interaction of NADH and acetaldehyde.

The transmission of polar effects. Part VII. A proton magnetic resonance spectra study of substituted mesitylenes, durenes, anthracenes, and triptycenes

1968 ◽  
Vol 46 (24) ◽  
pp. 3903-3908 ◽  
Author(s):  
Keith Bowden ◽  
J. G. Irving ◽  
M. J. Price
Keyword(s):  
Dielectric Constant ◽  
Free Energy ◽  
Carbon Tetrachloride ◽  
Field Effect ◽  
Proton Magnetic Resonance ◽  
Chemical Shifts ◽  
Linear Free Energy ◽  
Solvent Dependence ◽  
Similar Dependence ◽  
Energy Relations

The chemical shifts of the ring protons in a series of monosubstituted mesitylenes and durenes, and of the 10-protons of a series of 9-substituted triptycenes and anthracenes have been measured in dimethyl sulfoxide, acetone, 2-methoxyethanol, and carbon tetrachloride. The solvent dependence of the substituent chemical shifts has been analyzed by linear free energy relations. The systems all show similar dependence which increases with increasing dielectric constant of the solvent. This does not result from the field effect being transmitted through the medium, but appears to arise from the formation of a hydrogen-bonded interaction between the solvent and the hydrogen of the solute. The substituent chemical shifts appear to arise from contributions from substituent field, resonance, magnetic anisotropy, and solvent effects.

Seasonal Photosynthesis and Partitioning of Nonstructural Carbohydrates in Leafy Spurge (Euphorbia esula)

Weed Science ◽  
2007 ◽  
Vol 55 (4) ◽  
pp. 346-351 ◽  
Author(s):  
Russ W. Gesch ◽  
Debra Palmquist ◽  
James V. Anderson
Keyword(s):  
Late Summer ◽  
Leafy Spurge ◽  
Adventitious Bud ◽  
Adventitious Buds ◽  
Continuous Increase ◽  
Carbohydrate Partitioning ◽  
Growing Seasons ◽  
Autumn Leaf ◽  
Carbohydrate Status ◽  
New Strategies

Previous evidence indicates that changes in well-defined phases of dormancy in underground adventitious buds of leafy spurge in late summer and autumn are regulated by complex sensing and signaling pathways involving aboveground sugar signals. However, little information exists concerning seasonal photosynthesis and carbohydrate partitioning of leafy spurge, although such information would help to elucidate the involvement of sugar in controlling bud dormancy. An outdoor study was conducted over two growing seasons to determine and model seasonal patterns of photosynthesis and aboveground carbohydrate partitioning and their relationship to underground adventitious bud carbohydrate status. Photosynthesis and total nonstructural carbohydrate (TNC) content of aboveground tissues was greatest during vegetative growth. Photosynthesis gradually declined over the growing season, whereas TNC decreased sharply during flowering, followed by a gradual decline between midsummer and autumn. Leaf starch increased dramatically to midsummer before declining sharply throughout late summer and early autumn, whereas sucrose content responded inversely, indicating a mobilization of starch reserves and export of sugars to overwintering belowground sink tissues. Because newly formed underground adventitious buds showed a continuous increase in TNC from midsummer through autumn, export of sugars from aboveground tissues likely contributed to the increase in TNC. These results may facilitate new strategies for biological control of leafy spurge.

Requirements and interpretation of linear free energy relations

1984 ◽  
Vol 106 (10) ◽  
pp. 2772-2774 ◽  
Author(s):  
Peter E. Doan ◽  
Russell S. Drago
Keyword(s):  
Free Energy ◽  
Linear Free Energy ◽  
Energy Relations
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