Hubungan Antara Kondisi Tajuk Eucalyptus pellita F. Muell dan Infeksi Penyakit Busuk Akar

Abstract

ABSTRACT Functional disruption of cells and tissues within individual leaves due to pests and diseases infection subsequently causes in deterioration of crown, canopy contraction, and even tree death. Crown condition usually used as visual indicator for tree health assessment. Root-rot is considered as the most damaging disease for Eucalyptus pellita plantations. Methodology for the detection of rootrot at an early stage is required. In order to develop root rot detection method, this study investigates relationship between crown symptoms and root rot disease in E. pellita plantation. A visual assessment method to classify the crown condition of trees in plantations of E. pellita was developed. Repeatability, reproducibility and reliability of the developed method were examined by conducting repeated surveys. Applicability of the method to indicate root-rot incidence and severity at individual tree level was tested in seven plots. At the plot level, the crown-conditions were significantly correlated with the incidence and severity of root rot. At the tree level, the crown conditions were not significantly correlated with root-rot incidence and severity. Probability of these crown-indicators for estimating root-rot incidence and severity in individual tree is 61.4% and 41.6%, respectively. In order to prevent risks of massive productivity loss, root-rot site risk assessments Functional disruption of cells and tissues within individual leaves due to pests and diseases infection subsequently causes in deterioration of crown, canopy contraction, and even tree death. Crown condition usually used as visual indicator for tree health assessment. Root-rot is considered as the most damaging disease for Eucalyptus pellita plantations. Methodology for the detection of rootrot at an early stage is required. In order to develop root rot detection method, this study investigates relationship between crown symptoms and root rot disease in E. pellita plantation. A visual assessment method to classify the crown condition of trees in plantations of E. pellita was developed. Repeatability, reproducibility and reliability of the developed method were examined by conducting repeated surveys. Applicability of the method to indicate root-rot incidence and severity at individual tree level was tested in seven plots. At the plot level, the crown-conditions were significantly correlated with the incidence and severity of root rot. At the tree level, the crown conditions were not …