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Carbohydrate Pools in Pine Tissues Grown Under Different Nutritional Environments

FS-SRS- 4154-203 - Seasonal Fluctuations in Carbohydrate Contents of Loblolly Pine Tissues Grown Under Different Nutritional Environments

Carbohydrate storage serves to buffer the tree during periods of low C gain relative to C use. Excess sugars accumulate as non-structural starch when C production exceeds growth demands, and conversely provide a buffer when consumption is greater than current production (Ericsson 1978). Starch acts as both a long-term and short-term storage polysaccharide in plants. It is accumulated during active photosynthesis and then mobilized and exported as sucrose for respiration. Differences in starch concentrations could indicate different rates of production, or shifts in allocation.

The mechanics by which site resources affect seasonal patterns of starch accumulation are of particular interest, as management practices shift toward increasing fertilizer use and silvicultural intensity. Understanding management impacts on C storage pools can lead to improved long-term productivity.

Objectives

The three primary objectives for this study were to:

  1. examine starch concentrations in all tissues and determine if treatments affected concentrations or seasonal patterns,
  2. quantify starch storage capacity and the plant component distribution of capacity by treatment, and
  3. compare treatment effects on stored starch as a percentage of annual production.

Products

Sampson, A.D., K.J. Johnson, K.H. Ludovici, T.M. Albaugh and C.A. Maier. 2001. Stand-scale correspondence in empirical and simulated labile carbohydrates in loblolly pine. Forest Science 47(1):60-68

Ludovici, K.H., H.L. Allen, T.M. Albaugh and P.D. Dougherty. 2001. Seasonal Fluxes of Carbohydrates in Loblolly Pine Grown under Varied Nutrient and Irrigation Treatments. For. Ecol. Man. Accepted 9/00, In Press

Ludovici, K.H., H.L. Allen and P.M. Dougherty. 2002. Seasonal Fluctuations in Carbohydrate Contents of Three Root Size Classes From Loblolly Pines Grown Under Different Nutritional Environments. Tree Phys. (submitted 1/02)

(a) Albaugh, Allen, Dougherty, Kress and King. 1998. Leaf Area and Above- and Belowground Growth Responses of Loblolly Pine to Nutrient and Water additions. For. Sci. 44:317-328

(b) Schoeneberger et al. Methodology for enzymatic quantification of non-structural carbohydrates in pine tissues.