Epidemiology and etiology of ganoderma upper and basal stem rot in oil palm (elaeis guineensis jacq.) on peat in Sarawak, Malaysia

Oil palm (Elaeis guineensis) is the world’s most important oil producing crop which is mostly cultivated in Southeast Asia. The sustainability of oil palm is threatened by Ganoderma species that cause upper stem rot (USR) and basal stem rot (BSR). Basal stem rot is a prominent disease of oil palm...

Full description

Saved in:
Bibliographic Details
Main Author: Mohd Rashid, Mohd Rakib
Format: Thesis
Language:English
Published: 2015
Subjects:
Online Access:http://psasir.upm.edu.my/id/eprint/78171/1/FSPM%202015%202%20ir.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
id my-upm-ir.78171
record_format uketd_dc
institution Universiti Putra Malaysia
collection PSAS Institutional Repository
language English
advisor Bong, Joseph Choon Fah
topic Oil palm - Malaysia
Peat soils - Malaysia
Peatlands - Malaysia
spellingShingle Oil palm - Malaysia
Peat soils - Malaysia
Peatlands - Malaysia
Mohd Rashid, Mohd Rakib
Epidemiology and etiology of ganoderma upper and basal stem rot in oil palm (elaeis guineensis jacq.) on peat in Sarawak, Malaysia
description Oil palm (Elaeis guineensis) is the world’s most important oil producing crop which is mostly cultivated in Southeast Asia. The sustainability of oil palm is threatened by Ganoderma species that cause upper stem rot (USR) and basal stem rot (BSR). Basal stem rot is a prominent disease of oil palm, while little is known about USR. Lack of knowledge in terms of epidemiology and etiology of the diseases may lead to inaccurate disease control strategies. A study was conducted in oil palm plantations on peat in Sarawak, Malaysia, namely, Sessang Estate in Betong and Sungai Balim Estate in Miri. A total of 46 isolates of Ganoderma species from the USR- and BSR-infected palms were identified using multiplex PCR, and their in-vitro cultural and basidiospore morphological characteristics were investigated. It was found that both USR and BSR were associated with similar pathogens, where G. zonatum (71.7%) was dominant, followed by G. boninense (26.1%) and G. miniatocinctum (2.2%). This suggests that G. zonatum may have played a more vital role in the epidemiology of the disease than previously believed. All samples were found incompatible based on somatic compatibility test which indicated genetic heterogeneity of Ganoderma species in oil palm plantation and was suggestive of disease spread via spore dispersal that generated new genetically distinct individuals. There were also significant variations within and between Ganoderma species and no distinct relationship were found between species, disease types or geographical origins in terms of their cultural morphology and basidiospore characteristics. This suggests that any of the Ganoderma isolates found in this study have similar possibility of either causing USR or BSR. The pathogenic capability and aggressiveness of Ganoderma species were assessed based on external and internal infection symptoms using artificial inoculation on oil palm seedlings throughout 24 weeks period. All 46 Ganoderma samples tested were confirmed to be pathogenic to oil palm. Among them, G. zonatum isolated from USR-infected palms showed superior aggressiveness as compared with others with average foliar symptoms severity (FSS), disease severity index (DSI), stem bole lesion and primary root decay up to 33.18%, 43.78%, 42.20% and 48.55%, respectively. Hence, besides the prominent G. boninense and BSR, more studies should emphasize on G. zonatum and USR for more effective disease management since it was found as an increasingly important pathogen and disease in oil palm plantations, especially on peat areas in Sarawak. The infection of USR and BSR were mainly confirmed based on appearance of Ganoderma basidiomata on the stem, while the point of infection on the stem was the distinctive characteristic between them, where infection of Ganoderma species about one meter above ground indicated USR, while that at the base indicating BSR. USR and BSR disease coexisted in both sites, with lower USR (1.14-1.32%) as compared with BSR (3.48-4.01%) in Betong, while higher USR (3.66-6.02%) as compared with BSR (0.87-3.78%) in Miri throughout the study period. This also indicated that Ganoderma species infection in Miri was relatively higher than that in Betong. Geostatistical analysis of the Ganoderma species distribution revealed generally weak spatial dependence (>75%), which indicated that the distribution was random, and related to Ganoderma species spread via basidiospore dispersal at greater distance, instead of root-to-root infection. It was revealed that spatial distribution of Ganoderma species was at relatively greater density in Miri (15.1-100%) as compared with Betong (15.1- 30%). Although the distribution of Ganoderma species were random, the hotspot patterns generated allow site specific disease management as in precision agriculture and aid in sampling programmes for further investigations on the factors attributed to the patterns. Studies on macro- and micronutrients composition in relation to spatial distribution of Ganoderma species revealed that the foliar macro- and micronutrient elements affected the infection of Ganoderma species. Based on the four trials conducted at the two study sites, it was found that higher level of phosphorus (P), and lower and deficient level of copper (Cu) and zinc (Zn) in oil palms were associated with higher Ganoderma infection. In addition, lower and deficient level of Cu and Zn also could be related to higher Ganoderma infection in Miri as compared with Betong. Furthermore, there was no distinct factor in terms of soil and foliar chemical properties between USR and BSR. Therefore, this finding could be used as general guide to control Ganoderma species by giving more concern on manipulation of P, Cu and Zn level in oil palm plantations generally, and specifically in the two sites in this study for site-specific disease management as in precision agriculture.
format Thesis
qualification_level Doctorate
author Mohd Rashid, Mohd Rakib
author_facet Mohd Rashid, Mohd Rakib
author_sort Mohd Rashid, Mohd Rakib
title Epidemiology and etiology of ganoderma upper and basal stem rot in oil palm (elaeis guineensis jacq.) on peat in Sarawak, Malaysia
title_short Epidemiology and etiology of ganoderma upper and basal stem rot in oil palm (elaeis guineensis jacq.) on peat in Sarawak, Malaysia
title_full Epidemiology and etiology of ganoderma upper and basal stem rot in oil palm (elaeis guineensis jacq.) on peat in Sarawak, Malaysia
title_fullStr Epidemiology and etiology of ganoderma upper and basal stem rot in oil palm (elaeis guineensis jacq.) on peat in Sarawak, Malaysia
title_full_unstemmed Epidemiology and etiology of ganoderma upper and basal stem rot in oil palm (elaeis guineensis jacq.) on peat in Sarawak, Malaysia
title_sort epidemiology and etiology of ganoderma upper and basal stem rot in oil palm (elaeis guineensis jacq.) on peat in sarawak, malaysia
granting_institution Universiti Putra Malaysia
publishDate 2015
url http://psasir.upm.edu.my/id/eprint/78171/1/FSPM%202015%202%20ir.pdf
_version_ 1747813282781069312
spelling my-upm-ir.781712022-01-19T08:13:06Z Epidemiology and etiology of ganoderma upper and basal stem rot in oil palm (elaeis guineensis jacq.) on peat in Sarawak, Malaysia 2015-03 Mohd Rashid, Mohd Rakib Oil palm (Elaeis guineensis) is the world’s most important oil producing crop which is mostly cultivated in Southeast Asia. The sustainability of oil palm is threatened by Ganoderma species that cause upper stem rot (USR) and basal stem rot (BSR). Basal stem rot is a prominent disease of oil palm, while little is known about USR. Lack of knowledge in terms of epidemiology and etiology of the diseases may lead to inaccurate disease control strategies. A study was conducted in oil palm plantations on peat in Sarawak, Malaysia, namely, Sessang Estate in Betong and Sungai Balim Estate in Miri. A total of 46 isolates of Ganoderma species from the USR- and BSR-infected palms were identified using multiplex PCR, and their in-vitro cultural and basidiospore morphological characteristics were investigated. It was found that both USR and BSR were associated with similar pathogens, where G. zonatum (71.7%) was dominant, followed by G. boninense (26.1%) and G. miniatocinctum (2.2%). This suggests that G. zonatum may have played a more vital role in the epidemiology of the disease than previously believed. All samples were found incompatible based on somatic compatibility test which indicated genetic heterogeneity of Ganoderma species in oil palm plantation and was suggestive of disease spread via spore dispersal that generated new genetically distinct individuals. There were also significant variations within and between Ganoderma species and no distinct relationship were found between species, disease types or geographical origins in terms of their cultural morphology and basidiospore characteristics. This suggests that any of the Ganoderma isolates found in this study have similar possibility of either causing USR or BSR. The pathogenic capability and aggressiveness of Ganoderma species were assessed based on external and internal infection symptoms using artificial inoculation on oil palm seedlings throughout 24 weeks period. All 46 Ganoderma samples tested were confirmed to be pathogenic to oil palm. Among them, G. zonatum isolated from USR-infected palms showed superior aggressiveness as compared with others with average foliar symptoms severity (FSS), disease severity index (DSI), stem bole lesion and primary root decay up to 33.18%, 43.78%, 42.20% and 48.55%, respectively. Hence, besides the prominent G. boninense and BSR, more studies should emphasize on G. zonatum and USR for more effective disease management since it was found as an increasingly important pathogen and disease in oil palm plantations, especially on peat areas in Sarawak. The infection of USR and BSR were mainly confirmed based on appearance of Ganoderma basidiomata on the stem, while the point of infection on the stem was the distinctive characteristic between them, where infection of Ganoderma species about one meter above ground indicated USR, while that at the base indicating BSR. USR and BSR disease coexisted in both sites, with lower USR (1.14-1.32%) as compared with BSR (3.48-4.01%) in Betong, while higher USR (3.66-6.02%) as compared with BSR (0.87-3.78%) in Miri throughout the study period. This also indicated that Ganoderma species infection in Miri was relatively higher than that in Betong. Geostatistical analysis of the Ganoderma species distribution revealed generally weak spatial dependence (>75%), which indicated that the distribution was random, and related to Ganoderma species spread via basidiospore dispersal at greater distance, instead of root-to-root infection. It was revealed that spatial distribution of Ganoderma species was at relatively greater density in Miri (15.1-100%) as compared with Betong (15.1- 30%). Although the distribution of Ganoderma species were random, the hotspot patterns generated allow site specific disease management as in precision agriculture and aid in sampling programmes for further investigations on the factors attributed to the patterns. Studies on macro- and micronutrients composition in relation to spatial distribution of Ganoderma species revealed that the foliar macro- and micronutrient elements affected the infection of Ganoderma species. Based on the four trials conducted at the two study sites, it was found that higher level of phosphorus (P), and lower and deficient level of copper (Cu) and zinc (Zn) in oil palms were associated with higher Ganoderma infection. In addition, lower and deficient level of Cu and Zn also could be related to higher Ganoderma infection in Miri as compared with Betong. Furthermore, there was no distinct factor in terms of soil and foliar chemical properties between USR and BSR. Therefore, this finding could be used as general guide to control Ganoderma species by giving more concern on manipulation of P, Cu and Zn level in oil palm plantations generally, and specifically in the two sites in this study for site-specific disease management as in precision agriculture. Oil palm - Malaysia Peat soils - Malaysia Peatlands - Malaysia 2015-03 Thesis http://psasir.upm.edu.my/id/eprint/78171/ http://psasir.upm.edu.my/id/eprint/78171/1/FSPM%202015%202%20ir.pdf text en public doctoral Universiti Putra Malaysia Oil palm - Malaysia Peat soils - Malaysia Peatlands - Malaysia Bong, Joseph Choon Fah