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Tanaman nanas merupakan antara tanaman komoditi yang signifikan di Malaysia, termasuk di Sabah dan Sarawak. Namun begitu, tanaman nanas ini tidak terlepas dari serangan serangga perosak seperti koya yang berperanan sebagai vektor kepada penyakit Pineapple Mealybug Wilt-associated Virus (PMWaV) yang mampu mengurangkan hasil dan kualiti penghasilan nanas. Pengusaha nanas mengalami kesukaran dalam mengawal dan mengenalpasti spesies koya yang menyerang tanaman nanas disebabkan oleh saiznya yang kecil dan mempunyai variasi yang tinggi dengan dan antara spesies yang hampir. Maka, kajian ini bertujuan untuk melakukan pengecaman spesies koya dan semut yang berasosiasi dengan tanaman nanas di Sarawak dengan mengunakan analsisis DNA barkod. Pensampelan aktif bagi sampel koya dan semut telah dijalankan ditiga lokasi penanaman nanas di bahagian Bintulu, Sarawak, Malaysia (Samarakan, Kuala Tatau dan Universiti Putra Malaysia Kampus Bintulu (UPMKB)). Tiga spesies koya yang berasosiasi dengan tanaman nanas di Bintulu telah berjaya dikenalpasti iaitu Dysmicoccus brevipes (Cockerell), Ferrisia virgata (Cockerell) dan Planococcus minor (Maskell), serta lima spesies semut iaitu Anoplolepis gracilipes (Smith), Meranoplus bicolor (Guérin-Méneville), Iridomyrmex anceps (Roger), Tapinoma indicum (Forel) dan Crematogaster sp. Hasil kajian ini dapat membantu dalam pengecaman spesies yang tepat dan menambahbaik senarai spesies koya dan semut yang berasosiasi dengan tanaman nanas di Sarawak khasnya dan Malaysia amnya. Selain itu, hubungan simbiosis di antara koya dan semut sebagai agen penyebaran bagi koloni koya di kawasan penanaman nanas turut dibincangkan. Pengenalpastian spesies yang jitu diharap dapat membantu pengusaha dalam membangunkan kaedah pengawalan serangga perosak yang lestari.

Paddy husk (PH) is a waste item generated from rice production that can be used as an organic fertilizer through composting. High lignin content is an issue with PH composting as it impedes the production of high-quality organic fertilizer. Improvements to the composting process can enhance the agronomic properties of compost produced from PH. The objectives of this study were to: (i) determine the ability of Bacillus spp. in enhancing the decomposition of PH and (ii) determine the ability of Bacillus spp. in increasing the macronutrient content of composted PH. Different ligninolytic active Bacillus spp. from termite gut (either singly or a cocktail) were added to 7 of 9 compost boxes containing PH compost mixtures and were allowed to decompose for a period of 60 days. Each treatment was represented by 3 samples, and the compost boxes were arranged in a completely randomized design (CRD) with 3 replications. Results showed that the addition of Bacillus spp. promoted the production of matured compost within 60 days with significantly higher amounts of phosphorus, potassium, calcium, and magnesium. Germination index (GI) of all composted PH added with Bacillus spp. ranged from 82.51 to 95.83%, suggesting that composted PH has lower phytotoxicity than compost without Bacillus spp. isolate. In general, addition of Bacillus spp. to PH waste promoted the production of PH composts with improved macronutrient availability and lower phytotoxicity levels.

Oil palm bunch moth, Tirathaba mundella Walker is a notorious bunch feeding pest typically among oil palm aged 3-7 years old planted on peat. In order to manage the pest, an economic injury level (EIL) for the pest needs to be determined which could assist in decision-making if a control tactic is justified. In order to determine the EIL, the percentage of fertile oil palm fruitlets and oil to bunch content were determined for fruit bunches with different pest infestation severity. The severity was characterised based on the mean larvae present in fruit bunches and male inflorescences. The study found that the mean larvae count was positively correlated with the economic losses and number of parthenocarpic fruitlets. The overall oil extraction rate (OER) of moderate and severely infested fruit bunches was significantly reduced as compared to clean fruit bunches. Based on average crude palm oil (CPO) market price and production per hectare, an EIL for T. mundella was able to be estimated. This study suggested the EIL at 10% of oil palms per hectare moderately or severely infested. The finding of this study would benefit future pest management practice in oil palm plantation established on peatland.

Tirathaba mundella Walker has emerged as one of the most prominent bunch feeding pests in Sarawak peat oil palm estates. Insecticides application is inevitable to prevent economic loss. However, to protect insect pollinators which cohabitat with the pest and reduce the risk of resistance development among the pest to insecticides, rotation treatments with more than one pollinator-friendly insecticides is recommended. This paper examines the effectiveness of rotating several pollinator-friendly insecticides in controlling the pest. To assess the effectiveness of different rotation combination, a field study on a seven-year-old peat estate was carried out using several insecticides combinations and application intervals, then the level of infestation post-treatment was assessed. Significantly, the results showed that only four single rounds of insecticides application in a year would yield relatively better control than nine rounds of Bacillus thuringiensis applications. Overall, there was no significant difference in clean bunches percentages obtained between five rounds of treatment compared to only four rounds per year. The result strengthens our confidence that the optimum and most cost-effective approach for one-year protection against T. mundella was two rounds of 30.0 g active ingredient of chlorantraniliprole per ha rotated with two rounds of 25.0 g active ingredient of chromafenozide. The material cost was calculated as RM 351.20 per ha per year. The findings of this study would benefit future pest management practice in oil palm plantation established on peatland.

Tropical mountain forests are vital components of global floristic diversity as well as the hydrological cycle but have been extensively exploited. However, the impacts of human disturbances on changes in biomass and regional forest variation are not well documented in tropical mountainous regions. This study was conducted on the Payeh Maga Highland, Sarawak, Malaysia thirty years after logging at three elevational zones namely upper dipterocarp forest (UDF), lower-montane oak-laurel forest (LOF), and upper montane forest (UMF). Stand and growth dynamics were assessed for 12 months to estimate the tree growth rate and the aboveground biomass (AGB) of logged and unlogged forests at various elevations. Significant differences between logged-over and primary plots were observed in diameter at breast height (dbh) and basal area growth in the UMF. AGB recovery in the LOF plots was significantly slower that in other plot types. After three decades, the UDF and the UMF plots had AGB values similar to those of their primary plots. This study indicated that selective logging practices need to be improved to enhance the sustainability of timber production. Long-term monitoring, along with the establishment of more plots and the measurement of additional tree-competition parameters, is needed to clarify outstanding uncertainties.

Exploration of new environment provide an opportunity for better probiotics to be applied as valuable functional food. One interesting ecosystem is the gut of termites, where it contains bacterial populations to assist the host in extracting energy from polysaccharides of heavy fibre diet. This study screen, isolate and identify potential probiotic microorganisms from the hindgut of termites particularly from the species Coptotermes curvignathus. Bacterial isolates from the gut of Coptotermes curvignathus were tested for their potential as probiotics, with special reference to resistance to low pH, and tolerance to bile. The preliminary result showed that ten isolates can survive in low pH and five can survive in bile concentration. The five isolates were further tested on high concentrations of bile, antibiotic resistance and antimicrobial activity against pathogen i.e. Escherichia coli, Salmonella typhi, Shigella dysenteriae, Staphylococcus aureus, Vibrio cholera and Enterococcus faecalis tested by well diffusion method. For antibiotic resistance analysis, erythromycin, gentamycin, cefotaxime, meropenem, chloramphenicol, tetracycline, ciprofloxacin, and ampicillin were included by the disc-diffusion method. The isolate ATP022 had thrived well in low pH condition. The isolate ATP023 showed good capability in antibiotic resistance evaluation. The isolate ATP028 grows well in stimulated gastrointestinal juice. Moreover, the isolate ATP028 showed good result in tolerance in high concentration of bile. However, all isolates including the established probiotics i.e. Lactobacillus rhamnosus, did not perform well in the antimicrobial activity against pathogens. All five bacterial isolates were revealed from the genus Citrobacter. In conclusion, the ATP028 and ATP023, isolated form the gut of termite Coptotermes curvignathus have the best potential as probiotic with high tolerance to stimulated gastrointestinal juice, bile salts and antibiotic test.

Tirathaba mundella Walker is an important pest in many oil palm plantations especially those established on peatland. The life cycle of T. mundella has not been described in detail despite its economic importance. This study aimed to describe the bionomic characteristics of T. mundella, rearing on an artificial diet, at 25 oC. The duration of a complete metamorphosis cycle of T. mundella was about 51.63 ± 3.80 days. The incubation period was the shortest (3.33 ± 0.80 days.), The most detrimental stage of the pest to oil palm is at larval stage, which took 33.90 ± 2.60 days before pupating. The pupal period took about 5 to 11 days with a mean ± SD period of 8.53 ± 1.48 days. The average of the adult’s longevity was about 6.05 ± 1.81 days. There is no statistical difference between the duration of male and female longevity. Adult male and female moths reared in captivity feeded with 10% sucrose solution would mate readily and produce fertile eggs. The mean preoviposition period were 4 days. Successful of rearing T. mundella using artificial diet under laboratory conditions promises laboratory assessment for pesticide development which is less tedious and time consuming than conventional field experiments.

Prebiotics are any undigested food ingredients that are selectively fermented and allow for specific changes in the gut microbiota, thus improving the hosts’ health. In order to assess the potential of a food component to be considered as a prebiotic ingredient, several in vitro and in vivo experimentations need to be performed to provide scientific substantiation. In vitro studies are widely used because they are faster, cheaper, and more ethical compared to in vivo studies. However, in vitro studies faced difficulties in simulating the highly complex physiological and physiochemical events occurring in animal and human digestive tracts. Therefore, it is recommended that the results of in vitro studies be justified with in vivo experimentations to support their specific methodologies. Devised standard procedures for the evaluation and validation of prebiotic ingredients will boost confidence among the scientific community, approval of regulators, and acceptance from consumers on prebiotics and functional food science.

There are some confusion among agriculturists on the species of Tirathba beetles that are infesting on oil palm and coconut trees. Many thought they are the same species.nIn this study, the mitochondrial DNA Cytochrome oxidase subunit I (COI) of Tirathaba pest infested oil palm and coconut tree were compared. The mitochondrial DNAnCytochrome oxidase subunit I (COI) gene of the targeted Tirathaba sp. infesting onnoil palm and coconut tree were sequenced. The sequences were trimmed to remove gaps and produce a final aligned fragment of 603 bp for oil palm Tirathaba samplenand 602 bp for coconut pest sample. The DNA sequences were analyzed with other Tirathaba sp. sequences available in Gene bank using phylogenetic tree constructed with Neighbor-Joining (NJ) and genetic distance analysis algorithms. The result of this study indicates they were two different species. This knowledge will provide important data elements in the development of pest management strategy.

Bacteria and enzymes in the gut of termites play an important role to digest lignocellulosic material. Coptotermes curvignathus is one of the very few destructive species that can infest living plants. In this study, five bacteria isolated from C. curvignathus gut; four aerobic Bacillus spp. and an anaerobic uncultured bacterium were identified to produce endoglucanase with molecular size of 11 kDa which is significantly smaller than the endoglucanase produced by Reticulitermes speratus. Biolog reader identification showed that TG117 and N45/1 were Bacillus cereus/thuringiensis, TG111 was Bacillus pseudomycoides and TG005 was Bacillus mycoides. Endoglucanase produced by aerobic isolate NA45/1 showed promising potential as an industrial enzyme with significantly higher enzymtic activity than the commercial cellulase from Aspergillus Niger (C1184 Sigma). Endoglucanase NA45/1 displayed enzymatic activity 0.3961 U at pH 9 and 45°C. The endoglucanase TG111 acted optimally at alkaline condition with 0.2294 U whereas endoglucanase TG117 functioned best at slightly acidic condition. This study showed that the termite gut has a wide range of endoglucanase enzymes with various optimum temperatures and pH.

Land degradation and declining soil fertility challenge the productivity of forest plantations. Changes in soil properties could act as indicators for monitoring forest plantation management and productivity. This study highlights changes in soil properties and stand productivity over time (1, 3, and 5 years) in an Acacia mangium plantation in Bintulu, Sarawak, Malaysia. Soil pH, total N concentration, and available P were found to decline significantly with stand age. Significant differences were observed between soil organic C for different stand ages, with the youngest stand showing the highest C. The study showed that the current A. mangium plantation was able to store 74.9, 89.9, and 138.9 t C ha-1 in the 1-, 3-, and 5-year-old stands, respectively, and soil was the main contributor for the total C pools. All soil chemical attributes showed declining trends with stand age. These declines indicated that the present management practices are not sustainable and that management inputs are necessary.

Coptotermes curvignathus (C. curvignathus) are subterranean termites that feed on living-tree as their sole diet,which consist mainly of cellulose, hemicelluloses, lignin, plant allele chemical and other environmental residues such as insecticide. The xenobiotic compounds, plant allele chemical and insecticide are hazardous to termites health and need to be transported out of their body via xenobiotic and detoxification metabolism. This paper highlighted the potential enzymes that play vital role in the xenobiotic and detoxification metabolism. Transcriptomic data were generated from 200 termite’s digestive system using Illumina HiSeq 2000. Raw data was trimmed and assembled by SOLEXAQA and Bowtie before loaded into Gene Ontology based data mining software, Blast2GO (B2G). The result showed that, C. curvignathus contain enzymes that involved in all three biotransformation phases of xenobiotic and detoxification metabolism, which included cytochrome P450s monooxygenases, glutathione S-transferase, carboxylesterase, UDPglucuronyltransferases and N-acetyltransferase. The result of this study is the first insight into Cc xenobiotic pathway.

Coptotermes curvignathus Holmgren is capable of feeding on living trees. This ability is attributed to their effective digestive system that is furnished by the termite's own cellulolytic enzymes and cooperative enzymes produced by their gut microbes. In this study, the identity of an array of diverse microbes residing in the gut of C. curvignathus was revealed by sequencing the near-full-length 16S rRNA genes. A total of 154 bacterial phylotypes were found. The Bacteroidetes was the most abundant phylum and accounted for about 65% of the gut microbial profile. This is followed by Firmicutes, Actinobacteria, Spirochetes, Proteobacteria, TM7, Deferribacteres, Planctomycetes, Verrucomicrobia, and Termite Group 1. Based on the phylogenetic study, this symbiosis can be a result of long coevolution of gut enterotypes with the phylogenic distribution, strong selection pressure in the gut, and other speculative pressures that determine bacterial biome to follow. The phylogenetic distribution of cloned rRNA genes in the bacterial domain that was considerably different from other termite reflects the strong selection pressures in the gut where a proportional composition of gut microbiome of C. curvignathus has established. The selection pressures could be linked to the unique diet preference of C. curvignathus that profoundly feeds on living trees. The delicate gut microbiome composition may provide available nutrients to the host as well as potential protection against opportunistic pathogen.

In a termite colony, the queen termite is the central figure which performs the vital task of procreation by laying thousands of eggs per day to give rise to the enormous number of termites within the colony. She does not work and rarely moves, but grows to very large size in the queen's chamber.

In the forest or in an oil palm station, we sometimes see soil mounds that could be up to 1 meter tall. These are termite mounds. The common termite species that is a mound builder is the Macrotermes gilvus Hagen. The mound is actually a sort of 'house' that contains numerous living 'quarters' or lamellae which are interconnected by an intricate network of tunnels for instant and efficient communication and accessibility, or escape.