Herbivory alters plant carbon assimilation, patterns of biomass allocation and nitrogen use efficiency

PESCHIUTTA, MARÍA L.; SCHOLZ, FABIÁN G.; GOLDSTEIN, GUILLERMO; BUCCI, SANDRA J.

ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY

GAUTHIER-VILLARS/EDITIONS ELSEVIER

Lugar: Paris; Año: 2017 p. 9 - 16

1146-609X

Herbivory can trigger physiological processes resulting in leaf and whole plant functional changes. The effects ofchronic infestation by an insect on leaf traits related to carbon and nitrogen economy in three Prunus aviumcultivars were assessed. Leaves from non-infested trees (control) and damaged leaves from infested trees wereselected. The insect larvae produce skeletonization of the leaves leaving relatively intact the vein network of the eaten leaves and the abaxial epidermal tissue. At the leaf level, nitrogen content per mass (Nmass) and per area (Narea), net photosynthesis per mass (Amass) and per area (Aarea), photosynthetic nitrogen-use efficiency (PNUE),leaf mass per area (LMA) and total leaf phenols content were measured in the three cultivars. All cultivarsresponded to herbivory in a similar fashion. The Nmass, Amass, and PNUE decreased, while LMA and total contentof phenols increased in partially damaged leaves. Increases in herbivore pressure resulted in lower leaf size andtotal leaf area per plant across cultivars. Despite this, stem cumulative growth tended to increase in infectedplants suggesting a change in the patterns of biomass allocation and in resources sequestration elicited byherbivory. A larger N investment in defenses instead of photosynthetic structures may explain the lower PNUEand Amass observed in damaged leaves. Some physiological changes due to herbivory partially compensate forthe cost of leaf removal buffering the carbon economy at the whole plant level.