Fungus Ganoderma Boninense Research Articles

Perkembangan Penyakit Busuk Batang pada Kelapa Sawit Pasca Peremajaan Tanaman

Basal stem rot caused by the fungus Ganoderma boninense is the major threat to oil palm plantations in Indonesia, especially for second generation. Handling oil palm residues during the replanting process greatly determines the fungal attack. This research aims to reveal how handling oil palm trunks affects G. boninense attacks on second generation oil palm plantations. The treatments studied were felled trunk and felled-chipped trunk, each represented by two blocks (five years old of oil palm) with a density of 143 trees/hectare. The results of the study showed that second generation oil palms had a very high prevalence of basal stem rot disease, even though there were differences in the incidence and severity of the disease. Chipping of felled trunk residues can slow the development of the disease. Management of palm residues has a major influence on the onset of this disease in replanted oil palms.

PH and temperatures optimation activity of crude chitinase of oil palm endophytic bacteria Bacillus cereus which have antagonistic properties on pathogenic fungi Ganoderma boninense

Endophytic bacteria is promised solution to suppress basal stem rot disease caused by fungus Ganoderma boninense. The antifungal activities of selected isolate endophytic bacteria from oil palm plantation in South Kalimantan was studied. Bacillus cereus was tested for its antifungal activities of crude chitinase and secondary metabolites against the growth of Ganoderma boninense mycelium with dual cultured method. The results were showed that chitinase had the largest inhibition zone (18.5%) against growth inhibition of fungi Ganoderma boninense’s mycelium. A series of optimation assays of chitinase activity were conducted at pH 3 to 8 with 0.5 interval, and temperature at 30 to 70°C, with 5°C interval. Specific chitinase activities was measured using the colorimetric method. The highest specific chitinase activity significantly at 1.66393±0.04807 mU/μg (95% confidence level) at pH 5.5 and temperature 45°C.

INFEKTIVITAS MIKORIZA TANAMAN KELAPA SAWIT (Elaeis guinennsis Jack.) YANG TERSERANG GANODERMA

Palm oil (Elaeis guineensis Jacq.) is an important plantation crop in Indonesia as a producer of vegetable oil and several other derivative products. Palm oil (CPO) production is 47.18 million tons and PKO 4.6 million tons (GAPKI 2019). One of the main obstacles in palm oil cultivation is the presence of biotic stress in the form of Stem Root Disease (BPB) caused by the fungus Ganoderma boninense Pat. is the most harmful disease. In several palm oil plantations in Indonesia, this disease has caused the death of up to 80% or more of the entire population of oil palm plantations. Several factors that influence the development of BPB disease in the field are plant age, soil type, nutrient status and replanting technique. The characteristics of Ganoderma include soil borne, necrotropic and have various means of self-defense, therefore, BPB disease control must be carried out in an integrated manner between the use of resistant palm oil plants, the use of superior biological control agents and technical culture measures. One of the prevention alternatives that can be done is by utilizing soil microbes that can be in symbiosis with palm oil roots, such as Arbuscular Mycorrhizal Fungi (AMF). Mycorrhizae play a role in improving soil health, are environmentally friendly and able to improve soil nutrient status and agricultural products. Therefore, it is necessary to conduct research on the infectivity of mycorrhizae on healthy plants and plants that are attacked by Ganoderma. Keywords : Ganoderma, Infectivity, Oil palm

Review Update on the Life Cycle, Plant-Microbe Interaction, Genomics, Detection and Control Strategies of the Oil Palm Pathogen Ganoderma boninense.

Simple SummaryPalm oil is one of the main crops produced in Southeast Asia. However, the palm oil plantations within the region were severely affected by the basal stem rot (BSR) disease, caused by Ganoderma boninense. The disease causes substantial economic losses to oil palm producers, especially Indonesia and Malaysia. This review will cover the current knowledge on G. boninense published within the last 10 years.Plant pathogens are key threats to agriculture and global food security, causing various crop diseases that lead to massive economic losses. Palm oil is a commodity export of economic importance in Southeast Asia, especially in Malaysia and Indonesia. However, the sustainability of oil palm plantations and production is threatened by basal stem rot (BSR), a devastating disease predominantly caused by the fungus Ganoderma boninense Pat. In Malaysia, infected trees have been reported in nearly 60% of plantation areas, and economic losses are estimated to reach up to ~USD500 million a year. This review covers the current knowledge of the mechanisms utilized by G. boninense during infection and the methods used in the disease management to reduce BSR, including cultural practices, chemical treatments and antagonistic microorganism manipulations. Newer developments arising from multi-omics technologies such as whole-genome sequencing (WGS) and RNA sequencing (RNA-Seq) are also reviewed. Future directions are proposed to increase the understanding of G. boninense invasion mechanisms against oil palm. It is hoped that this review can contribute towards an improved disease management and a sustainable oil palm production in this region.

Antifungal Peptides from a Burkholderia Strain Suppress Basal Stem Rot Disease of Oil Palm.

Basal stem rot (BSR) is the most common disease of oil palm (Elaeis guineensis) in Southeast Asia. BSR is caused by a white-rot fungus Ganoderma boninense. The disease is difficult to manage. Therefore, development of novel and environmentally safe approaches to control the disease is important. Species of Burkholderia are known to have diverse lifestyles, some of which can benefit plants by suppressing diseases or increasing plant growth. In the present study, antifungal peptides produced by a bacterial strain isolated from the rhizosphere of an oil palm tree, Burkholderia sp. strain CP01, exhibited strong growth inhibition on G. boninense. A loss-of-function mutant of CP01 was generated, and it has enabled the identification of a 1.2-kDa peptide and its variants as the active antifungal compounds. High-resolution mass spectrometry revealed six analogous compounds with monoisotopic masses similar to the previously reported cyclic lipopeptides occidiofungin and burkholdine. The antifungal compounds of CP01 were secreted into media, and we sought to use CP01 culture extract without living cells to control BSR disease. Glasshouse experiments showed that CP01 culture extract suppressed BSR disease in oil palm seedlings. The ability of CP01 to produce an antifungal substance and suppress plant disease suggests its potential applications as a biofungicide in agriculture.

Analysis of rhizobacterial community associated with the occurrence of Ganoderma basal stem rot disease in oil palm by Illumina next-generation sequencing.

The fungus Ganoderma boninense is a causal pathogen of basal stem rot, a serious disease of oil palm plantation systems. As previously observed, some oil palm trees show no appearance of disease symptoms (asymptomatic oil palm), although they have grown close to a tree that showed severe symptoms of basal stem rot disease (symptomatic oil palm). The microbial community difference between asymptomatic and symptomatic oil palm will help understand disease suppression. Thus, in this study, rhizosphere soil was sampled around asymptomatic (OP-G) and symptomatic (OP + G) oil palm trees in Ganoderma-infected oil palm orchards. Illumina next-generation sequencing (NGS), bioinformatics analysis, bacterial diversity, and soil physicochemical properties were evaluated. The results demonstrated that soil physicochemical properties and species richness around rhizosphere soil of OP-G and OP + G samples were not significantly different. The age of the oil palm trees and oil palm variety showed negligible correlation and were not significant with bacterial diversity. However, the top ten most abundant analysis of the bacterial communities showed that phyla Actinobacteria and Firmicutes were significantly increased in rhizosphere soil around OP-G samples relative to the OP+ G samples. The unique operational taxonomic units (OTUs) of OP-G (2137) were higher than in the OP+ G samples (1747 OTUs). These bacterial communities have been reported as biological control agents and/or plant growth-promoting rhizosphere bacteria that are related to disease suppression. Thus, the data provided are useful for developing suppressive soil to biologically control G. boninense.

Identification of Oil Palm's Consistently Upregulated Genes during Early Infections of Ganoderma boninense via RNA-Seq Technology and Real-Time Quantitative PCR.

Basal stem rot (BSR) disease caused by pathogenic fungus Ganoderma boninense is a significant concern in the oil palm industry. G. boninense infection in oil palm induces defense-related genes. To understand oil palm defense mechanisms in response to fungal invasion, we analyzed differentially expressed genes (DEGs) derived from RNA-sequencing (RNA-seq) transcriptomic libraries of oil palm roots infected with G. boninense. A total of 126 DEGs were detected from the transcriptomic libraries of G. boninense-infected root tissues at different infection stages. Functional annotation via pathway enrichment analyses revealed that the DEGs were involved in the defense response against the pathogen. The expression of the selected DEGs was further confirmed using real-time quantitative PCR (qPCR) on independent oil palm seedlings and mature palm samples. Seven putative defense-related DEGs consistently showed upregulation in seedlings and mature plants during G. boninense infection. These seven genes might potentially be developed as biomarkers for the early detection of BSR in oil palm.

Hexaconazole-Micelle Nanodelivery System Prepared Using Different Surfactants for Ganoderma Antifungal Application.

Reports on fungicide-based agronanochemicals in combating disastrous basal stem rot disease in the oil palm industry are scant. Herein, we describe the potential of fungicide nanodelivery agents based on hexaconazole-micelle systems produced using three different surfactants; sodium dodecylbenze sulfonate (SDBS), sodium dodecyl sulfate (SDS) and Tween 80 (T80). The resulting nanodelivery systems were characterized and the results supported the encapsulation of the fungicide into the micelles of the surfactants. We have investigated in detail the size-dependent effects of the as-synthesized micelles towards the inhibition growth of Ganoderma Boninense fungi. All the nanodelivery systems indicate that their size decreased as the surfactant concentration was increased, and it directly affects the fungal inhibition. It was also found that Tween 80, a non-ionic surfactant gave the lowest effective concentration, the EC50 value of 2, on the pathogenic fungus Ganoderma boninense compared to the other anionic surfactants; SDBS and SDS. This study opens up a new generation of agronanofungicide of better efficacy for Ganoderma disease treatment.

Identification of non-ribosomal peptide synthetase in Ganoderma boninense Pat. that was expressed during the interaction with oil palm

Basal stem rot (BSR) of oil palm is a disastrous disease caused by a white-rot fungus Ganoderma boninense Pat. Non-ribosomal peptides (NRPs) synthesized by non-ribosomal peptide synthetases (NRPSs) are a group of secondary metabolites that act as fungal virulent factors during pathogenesis in the host. In this study, we aimed to isolate NRPS gene of G. boninense strain UPMGB001 and investigate the role of this gene during G. boninense-oil palm interaction. The isolated NRPS DNA fragment of 8322 bp was used to predict the putative peptide sequence of different domains and showed similarity with G. sinense (85%) at conserved motifs of three main NRPS domains. Phylogenetic analysis of NRPS peptide sequences demonstrated that NRPS of G. boninense belongs to the type VI siderophore family. The roots of 6-month-old oil palm seedlings were artificially inoculated for studying NRPS gene expression and disease severity in the greenhouse. The correlation between high disease severity (50%) and high expression (67-fold) of G. boninense NRPS gene at 4 months after inoculation and above indicated that this gene played a significant role in the advancement of BSR disease. Overall, these findings increase our knowledge on the gene structure of NRPS in G. boninense and its involvement in BSR pathogenesis as an effector gene.

Nursery evaluation of potential endophytic Trichoderma spp. from North Sumatra, Indonesia as a biocontrol agent against Ganoderma boninense

Basal stem rot (BSR) caused by the fungus Ganoderma boninense is regarded as the most destructive disease of oil palm (Elaeis guineensis Jaqc.) causes significant economic losses in the oil palm industry. An early study on the endophytic Trichoderma spp. showed they were promising potential in suppessing and preventing BSR. However, investigation on the effectiveness of endophytic Trichoderma from North Sumatra, Indonesia in preventing BSR disease in oil palms still scarce. The aim of this study was to evaluate the effectiveness of endophytic Trichoderma from North Sumatra, Indonesia in preventing BSR disease in the nursery. The active Trichoderma mixture (ATM) was prepared by first grown in PDA for six days before mixed and homogenized in 3 ml of sterile water. The mixture was later inoculated with a ratio of 1 ml to 150 g of mixture of cooked and sterilized broken corn and rice (3:4) medium. ATM was further dried and mixed homogeneously with zeolite (1:10) for application in the nursery. The potential endophytic Trichoderma spp. in suppressing BSR was monitored in the nursery for ten months. The external and internal symptoms of disease development were observed and disease incidence (DI) was also recorded. Total phenolic content (TPC) was analyzed using Folin-Ciocalteu method to determine the effect of endophytic Trichoderma in inducing oil palm seedling resistance to BSR disease. The result showed that application of endophytic Trichoderma spp. was found to be effective in suppressing G. boninense infection, where endophytic T. reesei ET501 to be the most effective in preventing disease incidence (DI) with only 13.4 % infection after ten months of observation followed by endophytic T. asperellum ET537 (48.4 %) and T. asperellum ET523 (71.8 %), respectively. Application of endophytic Trichoderma spp. in the nursery also exhibited the potential in inducing TPC amount and it helps in developing resistance in oil palm seedlings, thus protecting the seedlings from G. boninense infection.

Ganoderma diversity from smallholder oil palm plantations in peatlands of Kampar District, Indonesia based on mycelia morphology and somatic incompatibility

Abstract. Hamzah A, Saputra R, Puspita F, Nasrul B, Irfandri, Depari NS. 2021. Ganoderma diversity from smallholder oil palm plantations in peatlands of Kampar District, Indonesia, based on mycelia morphology and somatic incompatibility. Biodiversitas 22: 16-22. Basal Stem Rot disease is caused by the pathogenic fungus Ganoderma boninense which has caused major economic losses in the palm oil industry. Ganoderma boninense has been reported not only infecting crops in the field, but also attacking at the immature phase of the plant even in the nursery. Studies related to Ganoderma diversity in oil palm plantations in Riau, Indonesia have not been widely reported. Ganoderma genetic diversity is important because its provide information regarding the mechanism of infection and the spatial distribution. The Ganoderma spp. isolates were collected from three blocks of smallholder oil palm plantation in Deli Makmur Village, Kampar District, Riau Province, Indonesia and brought to Plant Disease Laboratory, Faculty of Agriculture, Riau University, Pekanbaru, Indonesia. This experimental research was conducted using six Ganoderma isolates (Gan1, Gan2, Gan3, Gan4, Gan5, and Gan6) on the parameters of colony diameter and growth speed, while for the parameters of the morphological diversity of Ganoderma mycelium and the diversity based on somatic incompatibility assay was carried out descriptively. The results of this study show that oil palm plants in smallholder plantations in Kampar District are infected by two groups of Ganoderma based on morphology characteristics using UPGMA dendrogram, but different among isolates based on genetically using somatic incompatibility assay. For the next confirmation, it is necessary to further identify whether the six isolates are different species using molecular identification.

Growth responses of oil palm seedling inoculated with Ganoderma boninense under competition with edible herbaceous plants

Basal stem rot (BSR) caused by long-term survival fungus Ganoderma boninense is the most important of oil palm disease that difficult to be controlled. Perennial herbaceous species are potentially developed for long-term BSR control and applied as mixed planting with oil palm. This research was aimed to study the competition effects of mixed planting with edible herbaceous perennial plants (edible canna (Canna indica), arrowroot (Maranta arundinacea), cocoyam (Xanthosoma sagittifolium), and water yam (Dioscorea alata) on growth of oil palm seedlings. Two competition trials (non-inoculated and Ganoderma-inoculated trial) were conducted. The herbaceous plants were grown together with oil palm seedling in a polybag filled with 40 L field soil. Mixed planting of Ganoderma-inoculated oil palm and herbaceous plants and grown on a large soil volume resulted in a minor infection with a high variation in severity leading to insignificant effect of herbaceous competition on Ganoderma infection. Herbaceous competition significantly suppressed oil palm seedling growth under both inoculated with Ganoderma and without inoculation. Arrowroot exhibited as the most competitive herbaceous species and followed by canna and cocoyam. Water yam showed a weak competitive against oil palm seedling since only a minor interference in all observed growth characteristics.

Application of Ground-Based LiDAR for Analysing Oil Palm Canopy Properties on the Occurrence of Basal Stem Rot (BSR) Disease

Ground-based LiDAR also known as Terrestrial Laser Scanning (TLS) technology is an active remote sensing imaging method said to be one of the latest advances and innovations for plant phenotyping. Basal Stem Rot (BSR) is the most destructive disease of oil palm in Malaysia that is caused by white-rot fungus Ganoderma boninense, the symptoms of which include flattening and hanging-down of the canopy, shorter leaves, wilting green fronds and smaller crown size. Therefore, until now there is no critical investigation on the characterisation of canopy architecture related to this disease using TLS method was carried out. This study proposed a novel technique of BSR classification at the oil palm canopy analysis using the point clouds data taken from the TLS. A total of 40 samples of oil palm trees at the age of nine-years-old were selected and 10 trees for each health level were randomly taken from the same plot. The trees were categorised into four health levels - T0, T1, T2 and T3, which represents the healthy, mildly infected, moderately infected and severely infected, respectively. The TLS scanner was mounted at a height of 1 m and each palm was scanned at four scan positions around the tree to get a full 3D image. Five parameters were analysed: S200 (canopy strata at 200 cm from the top), S850 (canopy strata at 850 cm from the top), crown pixel (number of pixels inside the crown), frond angle (degree of angle between fronds) and frond number. The results taken from statistical analysis revealed that frond number was the best single parameter to detect BSR disease as early as T1. In classification models, a linear model with a combination of parameters, ABD – A (frond number), B (frond angle) and D (S200), delivered the highest average accuracy for classification of healthy-unhealthy trees with an accuracy of 86.67 per cent. It also can classify the four severity levels of infection with an accuracy of 80 per cent. This model performed better when compared to the severity classification using frond number. The novelty of this research is therefore on the development of new approach to detect and classify BSR using point clouds data of TLS.

Identifikasi Ganoderma Pada Tanaman Kelapa Sawit Berbasis Reflektansi Gelombang Multispektral

Basal Stem Rot (BSR) is a fatal disease caused by the fungus Ganoderma boninense. Currently in Indonesia the identification of oil palm plants suffering from BSR is done by directly observing oil palm plants one by one and pressing the palm tree trunks. However the direct checking method is felt to be less effective and efficient, its need another better method for detecting BSR. This study aims to evaluate the Ganoderma attack by using a multispectral camera, applying a neural network method to analyze NDVI images, and analyzing the effect of altitude on the accuracy of multispectral camera performance. In this study, spectral data of oil palm plants were taken through the air at an altitude of 50 m, 60 m, and 70 m with a multispectral camera mounted on a UAV, then the spectral data were analyzed using artificial neural networks to identify oil palm plants that were attacked by Ganoderma and healthy plants. The results of this study conclude that multispectral cameras can identify oil palm plants that have been attacked by Ganoderma at an altitude of 50 m and 60 m with utilization of artificial neural networks.

Design and fabrication of PDMS microfluidics device for rapid and label-free DNA detection

Microfluidics explores the manipulation of fluid in small volume, a multidisciplinary field is imperative for DNA extraction. This study offers a simple yet substantial methodology for the fabrication of microfluidics structure-based polydimethylsiloxane (PDMS) biopolymer on a glass substrate with SU-8 photoresist for label-free detection of pathogenic genomic DNA. Two microfluidics designs for DNA detection were based on AutoCAD software, both contain two inlets and one outlet, with dimensions of 28 mm wide, and 18 mm long, and total surface area of 504 mm2. The designs were patterned in such particular sizes and dimensions to test fluid delivery and enhancement in biochemical processes in DNA extraction, while maintaining economical values as a disposable chip. Both microfluidics devices showed no leakage during fluid delivery, have heights of 97.97 and 103.44 μm, and surface roughness of 0.15 and 0.07 μm, respectively. DNA extraction from pathogenic fungus Ganoderma boninense was run on PDMS microfluidic device and UV–Vis analysis confirmed successful extraction with peaks found at 260–280 nm. Current–voltage (I–V) measurement confirmed the accuracy of microfluidic device for the specific pathogen with both real and synthetic samples of G. boninense illustrating the similar graph values of only 0.000005 A difference at 1.0 V after hybridization.

Automated, high-throughput DNA extraction protocol for disposable label free, microfluidics integrating DNA biosensor for oil palm pathogen, Ganoderma boninense

Basal Stem Rot and Upper Stem Rot diseases caused by pathogenic fungus Ganoderma boninense continue to be a major plight in the palm oil industry. Despite continuous research in combating the problem, resolution remains stagnant. Here, developed an automated, high-throughput DNA extraction protocol on microfluidics device for a quick, disposable, label-free detection, within 2 h of assessment. Microfluidics was designed using AutoCAD software, fabricated on microscopic glass substrate using negative photoresist (SU-8 2015) and molded with a biopolymer silicone, Polydimethylsiloxane. G. boninense and unknown pathogenic fungus isolated from rotten mushroom were grown and fractions of extracted DNA were pooled and analyzed for comparison along with synthetic ssDNA of G. boninense. Results from LPM and HPM show successful fabrication with ≤0.1 mm variance between the dimensions in the design before and after lithography process. The PDMS microfluidics show no leakage when run with DNA samples. Analyses from I-V measurement, UV–vis, FTIR, and PCR show comparable results between extracted and synthetic ssDNA of G. boninense and a contrast with the unknown pathogenic fungus, indicating a successful DNA extraction protocol via microfluidics for label-free identification of G. boninense. Optimization of DNA extraction can be further devised for applicability on lab-on-a-chip devices.

CRISPR/Cas9‐mediated knockout of an oil palm defense‐related gene to the pathogenic fungus Ganoderma boninense

Oil palm plantation in Indonesia is significantly affected by basal stem rot disease caused by the pathogenic fungus Ganoderma boninense. Tolerant oil palm cultivars toward G. boninense have been developed through a breeding program accelerated by the implementation of the CRISPR/Cas9 technology. This study was conducted to perform a gene knockout (KO) of oil palm that confers a putative defense‐related trait toward G. boninense. A plasmid pCRISPR_EMLP containing modules, i.e., 35S‐CaMV‐promoter‐driven CRISPR/Cas9, U6‐promoter‐driven sgRNA to the target EgEMLP gene (EL695076), and hygromycin resistance gene as the selectable marker, was established for Agrobacterium‐mediated delivery into oil palm calli (OPC). The transformed OPCs were regenerated and screened in DF (de Fossard) media containing hygromycin. The working concentration of hygromycin was successfully optimized for selection at 20 ppm. Through PCR‐based selection using HYG primers, we succeeded in discerning positive transformed OPC clones. The sequenced PCR products of genomic DNA as the template amplified using EMLP1 primers showed a point mutation, causing a frameshift in the edited EgEMLP and premature stop codon. Furthermore, in silico modeling demonstrated that the mutation resulted in a change in the C‐terminal region, affecting the tertiary protein structure. Moreover, electrophoresis analysis of PCR products of cDNA as the template from transformed OPC clones showed several samples with faint or undetected bands. This indicated that the CRISPR/Cas9 module induced a mutation that could destabilize the transcribed mRNA, e.g., premature degradation. Altogether, this study has successfully implemented CRISPR/Cas9 gene editing in oil palm in a model gene that is responsible for putative defense‐related traits toward the pathogenic fungus G. boninense.

Depletion of Indonesian oil palm plantations implied from modeling oil palm mortality and <i>Ganoderma boninense</i> rot under future climate

Currently there are increasing land-cover and land-management issues related to oil palm plantations. Palm oil is highly valuable and it is added to numerous commodities internationally with Indonesia being the most voluminous producer. The cultivation of oil palm affects the environment negatively, per se, threatening plantation sustainability from deforestation. Furthermore, the fungus Ganoderma boninense causes basal stem rot of oil palm, a major problem for plantation managers in Indonesia. Suitable future climate for growth of Indonesian oil palm, determined by employing the simulation programme, CLIMEX, has already been employed to create scenarios of oil palm mortality and diseases. This was achieved by combining CLIMEX with narrative models, a technique often employed in climate studies. Determinations of the percentage of oil palm that survive climate and do not have basal stem rot have also been provided. The current paper considers these scenarios for Indonesia and regions for the first time. The models assume no change in the future climate scenarios and that effective mitigation is not taken. The effects on plantation sustainability are considered. Climate will not affect the incidence of basal stem rot greatly until 2050, but the situation will deteriorate thereafter. Sumatra and Java are especially affected and plantations may be unsustainable quickly, whereas Papua and Sulawesi may be able to sustain the crop longer. However, deforestation in Papua and Sulawesi is highly undesirable. Methods to manage climate effects on oil palm and reduce basal stem rot are described. Plantation managers can use the earlier assessments herein to indicate if the later ones are accurate and plan to ameliorate the problems. Conclusions indicate that palm oil production may be unsustainable in Indonesia by 2050 from loss of plantations thus requiring action immediately.

Draft Genome Sequence of the Phytopathogenic Fungus Ganoderma boninense, the Causal Agent of Basal Stem Rot Disease on Oil Palm.

ABSTRACTGanoderma boninense is the dominant fungal pathogen of basal stem rot (BSR) disease on Elaeis guineensis. We sequenced the nuclear genome of mycelia using both Illumina and Pacific Biosciences platforms for assembly of scaffolds. The draft genome comprised 79.24 Mb, 495 scaffolds, and 26,226 predicted coding sequences.

A Rapid Inoculation Method for Infection of Ganoderma in Oil Palm

Basal stem rot (BSR) is a major disease of oil palm plantation caused by pathogenic fungus Ganoderma boninense. To overcome the disease, development of resistant or tolerantoil palms is crucial for susta inable production of palm oil. Thus a reliable and rapid method to assess resistance of oil palm to BSR is important. Here we report an inoculation technique designated as mycelium inoculation technique. This method is faster and simpler compared to the traditional technique using rubber wood block. The technique that we developed results in consistency of infection and disease can be evaluated as early as two weeks after inoculation with G. boninense. Furthermore, this method is also able to differentially assess resistant and susceptible palm seedlings to BSR. The results show that this new inoculation technique can be used as a routine method to infect oil palm seedlings and can be utilised for development of resistant cultivar of oil palm to G. boninense.