Work

Foliar Nutritional Status Influences Herbivory Caused by Gonipterus platensis in Eucalyptus globulus, E. nitens and Their Hybrids

Year: 2025

Type: article

Abstract: Eucalyptus plantations worldwide experience significant productivity losses due to herbivory caused by the weevil Gonipterus platensis (Coleoptera: Curculionidae. Marelli 1927); however, the role of leaf nutritional status in host preference remains poorly understood. In this study, we evaluated the incidence and severity of defoliation on two seed-propagated eucalypts—Eucalyptus globulus Labill. and Eucalyptus nitens Maiden, as well as two clonally propagated E. nitens × E. globulus hybrids—at a trial site in Mulchén, Chile. Sampling occurred after peak weevil activity (December 2022) and during austral autumn (May 2023). We determined foliar concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), boron (B), carbon (C), and the carbon-to-nitrogen (C/N) ratio, and analyzed their relationships with herbivory using ANOVA, principal component analysis (PCA), and linear regression. Overall defoliation was low (<7%), but significantly higher on E. globulus, with hybrids exhibiting intermediate damage. Seasonally, N and Mg concentrations declined, while K and Ca levels increased, resulting in an elevated C/N ratio in autumn. A positive correlation was observed between leaf Ca concentration and both the incidence and severity of herbivory during peak activity in the susceptible E. globulus genotype (R2 = 0.96, p < 0.05). These findings suggest that calcium accumulation may influence weevil feeding preferences. Further research should explore nutrient-mediated resistance to guide selection and fertilization strategies for developing more resilient eucalyptus varieties.

Source: Forests

DOI: 10.3390/f16111618

Authors: Clara Ricci, Regis Le-Feuvre, Matías Pincheira, Claudia Bonomelli, Rafael Rubilar, Priscila Moraga-Suazo

Institutions: Pontificia Universidad Católica de Chile, University of Concepción

Language: English

Topic: Insect-Plant Interactions and Control

Subfield: Insect Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDGs: Zero hunger, Life on land

Open Access status: gold

Estimated APC paid: $3,137