Management of basidiomycete root‐ and stem‐rot diseases in oil palm, rubber and tropical hardwood plantation crops

Abstract

Basal stem-rot and root-rot diseases caused by basidiomycete fungal pathogens are naturally and widely occurring in a large range of hosts. However, they significantly reduce the productivity of several economically important plantation-crop industries in tropical countries. Oil palm, rubber, acacias and eucalypts are all susceptible to basidiomycete rot pathogens to varying degrees and there is no absolute disease resistance. The causal pathogens are persistent as they remain present in wood or crop debris even in the absence of living members of the host species. Disease build-up is often rapid and can reach economically unacceptable levels in the absence of interventions to contain the disease. This study reviews the biology and detection of root-rot disease in oil palm, rubber and hardwood crops with a specific focus on management strategies undertaken in South-East Asia. The diseases caused by basidiomycete rot pathogens in this region are intractable and require an integrated approach to disease management, as it is unlikely that any one control strategy will succeed. In contrast, there has been significant success in reducing losses from basidiomycete rot from pathogens in the northern hemisphere, especially with Heterobasidion annosum sensu lato in forest trees, research being often supported by the establishment of long-term trials required to understand the origins and types of disease. In the tropics, progress has been more fragmented due to the low level of research funding, the problems involved with managing long-term research trials in the tropics, the confidentiality requirements of competitive industries and the lack of literature available in the public arena. This review collates a large body of information from disparate and often obscure sources for oil palm, rubber, acacias and eucalypts, tropical plantation crops that face similar types of stem-and root-rot disease problems. Lessons to be learned from the successes and failures of various management strategies with each type of crop are examined.

Oil palm natural diversity and the potential for yield improvement

“…The basal stem rot is lethal, infected plants stop producing fruit and eventually die. The average tree mortality rate of 3,7% is equivalent to losses of US$ 570 million per year (Mohammed et al, 2014). White rot fungi are characterized as facultative saprophytes, which are generally difficult to control.…”

“…Current practical solutions are biological control with Trichoderma spp. fungi, palm endophytes and implementation of correct agronomical and phytosanitary practices (Mohammed et al, 2014). …”

RETRACTED: <i>Management of White Root Rot Disease (Fomes) in Hevea brasiliensis Plantations in Cameroon</i>

“…Its pathogen also survives with fruiting bodies on dead trees, branches/twigs, decomposing tree stumps and even on decaying leaves [6]. The main constrain to the success of control methods for this disease is that treatments are only carried out on diseased trees and their effectiveness depends on reliable and early detection of pathogens [7]. Chemical treatment, which helps to restrain the epidemics [2] [8] is one of the currently recommended control methods.…”

Structural host responses of Acacia mangium and Eucalyptus pellita to artificial infection with the root rot pathogen, Ganoderma philippii

“…The screening of genetic trials in the field and artificial inoculation in pot experiments with A. mangium has failed to find any exploitable trends in resistance to root rot disease (Mohammed et al., ). In previous studies, resistance or susceptibility has been related to the timing and morphology of WPs (Cleary et al., ; Solla et al., ).…”

“…The aim of this study was to examine the histology of host responses to infection by G. philippii in the roots and basal stem of the susceptible host, A. mangium, and to compare these responses to the more resistant host, Eucalyptus pellita F. Muell. Results from a previous pot trial provided some evidence that E. pellita has higher resistance and as such, this species has been identified as a potentially viable alternative to A. mangium in Indonesia (Mohammed, Rimbawanto, & Page, ). As part of this work, we also describe the morphology of the mycelial sheath of G. philippii ‐infected roots and basal stem.…”