Genetic Diversity and Demographic History of Ganoderma boninense in Oil Palm Plantations of Sarawak, Malaysia Inferred from ITS Regions

Abstract

Ganoderma boninense causes basal stem rot (BSR) and is responsible for substantial economic losses to Southeast Asia’s palm oil industry. Sarawak, a major producer in Malaysia, is also affected by this disease. Emergence of BSR in oil palm planted on peat throughout Sarawak is alarming as the soil type was previously regarded as non-conducive. Phylogenetic analysis indicated a single species, G. boninense as the cause of BSR in Sarawak. Information on evolutionary and demographic history for G. boninense in Sarawak inferred through informative genes is lacking. Hence, a haplotype study on single nucleotide polymorphisms in internal transcribed spacers (SNPs-ITS) of G. boninense was carried out. Sequence variations were analysed for population structure, phylogenetic and phylogeographic relationships. The internal transcribed spacers (ITS) region of 117 isolates from four populations in eight locations across Sarawak coastal areas revealed seven haplotypes. A major haplotype, designated GbHap1 (81.2%), was found throughout all sampling locations. Single nucleotide polymorphisms were observed mainly in the ITS1 region. The genetic structure was not detected, and genetic distance did not correlate with geographical distance. Haplotype network analysis suggested evidence of recent demographic expansion. Low genetic differences among populations also suggested that these isolates belong to a single G. boninense founder population adapting to oil palm as the host.

Transcriptional profile of oil palm pathogen, Ganoderma boninense, reveals activation of lignin degradation machinery and possible evasion of host immune response

“…G. boninense , a soil-borne fungus that colonizes its host through the roots [ 10 ], poses a serious threat to oil palm plantations in southeast Asia [ 11 ]. Similarly, G. zonatum has been described as a pathogen on palms in the southeastern US [ 12 ].…”

Genome-Wide Characterization and Comparative Analysis of MYB Transcription Factors in Ganoderma Species

“…Polysaccharides ( Cör et al 2018 ; Ma et al 2018 ) and triterpenes ( Liang et al 2019 ; Wahba et al 2019 ) with vital medicinal functions have drawn the attention of researchers. In addition, great progress has been made in the classification/identification ( Liao et al 2015 ), genetic diversity ( Midot et al 2019 ), and fruiting body development ( Sudheer et al 2018 ) of Ganoderma species.…”

Current strategies and perspectives in detection and control of basal stem rot of oil palm

“…One of the factors is OP is prone to attack by various diseases ( Corley and Tinker, 2015 ) and fruit bunch yield reduction caused by pest and diseases may contribute up to a yield loss ~50 to 80% ( Woittiez et al, 2017 ). Basal stem rot (BSR) caused by the fungus Ganoderma boninense, is of major concern to sustainability in Malaysia and Indonesia and it is predicted that more than 60 million mature OP could be infected in Malaysia ( Midot et al, 2019 , Olaniyi and Szulczyk, 2020 ).…”

“…Peat soil was once assumed to be non-conducive for BSR disease development due to their acidic nature, however, disease incidence in oil palm planted on peat have been reported ( Azahar et al, 2011 , Parthiban et al, 2016 ; ( Rashid et al, 2014 ). Therefore, growing OP in peat soils is no longer considered a barrier to the disease ( Midot et al, 2019 ) indicating that a significant change in climatic conditions has occurred. Further, climate change will have a devastating effect if not ameliorated.…”