Nonstructural Carbohydrate Depletion in Snowberry (Symphoricarpus oreophilus)

Abstract

Nonstructural carbohydrate (NC) concentrations in defoliated snowberry (Symphoricarpus oreophilus) plants were compared over two seasons with trends of NC concentrations in untreated plants. Nonstructural carbohydrate concentrations in small roots and stems of defoliated plants decreased slowly from the time of initial defoliation. The NC concentrations in large roots and root crowns remained stable until prolonged, intense defoliation caused a significant decrease in NC concentrations in these plant parts. NC concentrations in stems, large roots, and root crowns decreased significantly before plant death. The decrease in NC concentrations in large roots and root crowns coincide with an increase in NC concentrations of stems prior to leaf production. Defoliated plants did not produce new stems after defoliation began and stem mortality during dormancy was great. NC concentrations apparently were inadequate to support the entire plant through dormancy. Nonstructural carbohydrates remaining in dead plant parts constitute an unused portion of the carbohydrate reserves.