Mimicry of formaldehyde as aldehyde: a potential and novel chemical compound to control storage pests

Tribolium castaneum is one of the most pervasive pests to threaten the storage of rice in Malaysia; thus, control methods are being studied to overcome this problem. The main objective of this study is to measure the efficacy of paint to attract T. castaneum. Based on preliminary results regarding olfactory responses, the formaldehyde compound in paint is highlighted as a potential and alternative method to be used as bait to trap the T. castaneum that infest rice storage warehouses. This result is likely due to the paint’s main element, formaldehyde, which releases a pungent smell and attracts the pests. Chemically, formaldehyde is a simpler form of aldehyde, with the formula CH2O. The idea to use paint in this study was inspired by the reports of warehouse workers who declared that insect pests are attracted to the paint that is stored in warehouses. Interestingly, this preliminary finding results in an interesting conclusion and a novel outcome in the field of stored product research. To this end, researchers recommend a paint or formaldehyde compound to serve as bait capable of attracting T. castaneum

A noninvasive molecular approach: exploiting species-locus-specific PCR primers in defeating numts and DNA cross-contamination of cercopithecidae

The lack of a standardized, noninvasive molecular approach to studying genetic aspects of primates has made it hard for primatologists to decode the evolutionary history of these species. Researchers must optimize their own techniques to fully exploit the available samples. Lack of species-locus-specific primers also contributes to difficulties in using noninvasive genetic samples. Thus, the objectives of this study were to develop a standardized technique to collecting samples noninvasively, propose newly designed species-locus-specific primers, and optimize conditions for polymerase chain reaction (PCR) for Macaca fascicularis, M. nemestrina, Trachypithecus cristatus, and T. obscurus. Nine new species-locus-specific primers for three different loci of mitochondrial DNA, namely D-loop, cytochrome oxidase subunit I (COI), and cytochrome b, were successfully designed. These primers proved to be efficient in amplifying larger datasets (up to ~1,000 bp) of the targeted species in the optimized PCR conditions. The species-locus-specific primers are able to anneal to host DNA alone in highly contaminated feces of highlighted species. They can also offer alternatives measures in avoiding contamination related to nuclear insertion of mitochondrial pseudogenes (numts)

The significance of free air co2 enrichment and open roof ventilatio greenhouse systems in a study of mealworm beetle, Tenebrio molitor L. (coleoptera: tenebrionidae)

Tenebrio molitor L. (Coleoptera: Tenebrionidae) is an insect storage pest that has been used as a subject in Integrated Pest Management (IPM) research. The aim of this study is to determine the importance of conducting insect-related studies, especially on T. molitor under a Free Air CO2 Enrichment (FACE) System and Open Roof Ventilation Greenhouse System (ORVS). FACE system provides a natural microclimate and biotic interactions, while ORVS is an artificial environment with regulation of its environmental parameters. More accurate comparisons can be made to the results obtained under the similar environmental factors including elevated CO2 concentration. Based on the results, the mortality time of T. molitor adults in ORVS (5-6 weeks) is the fastest, followed by FACE (9-10 weeks) and RR as a control (11-12 weeks). The highest significant time difference shows by the last adult individual dead is between ORVS versus RR is 6 weeks. Therefore, mortality rate of T. molitor adult and their life span are directly proportional to the elevated CO2 concentration. It is shows that the higher concentration of CO2, with faster mortality rate and shorter the life span of the adults. Since the study of insects using both systems is still limited, the data from this preliminary study can be used as reference for future research

Altitudinal accumulation and diversity of leaf beetle (Coleoptera: Chrysomelidae) at Fraser’s Hill, Pahang

Most of the research on leaf beetles more focusing on their roles as a pest or biological control. On the ecological part is much understudied. So the objective of this study is to determine the accumulation and diversity of leaf beetles at different altitude on Fraser’s Hill, Pahang. Sampling was done in Dec 2016 – Feb 2017 at lower (900 m a.s.l) altitudes by using sweep net from 10.00 a.m. to 2.00 p.m. A total of 296 individuals, 28 species and five subfamilies successfully collected. Galerucinae has the highest number of species and individuals with 14 and 154 respectively. Lower altitude has the highest individuals with 116 but has the lowest number of species with only 11. Meanwhile, sampling on Jan 2017 has the highest abundance of 108 individuals and 17 species. However, t-test indicates that there is no significant different between all Shannon index either by altitude-wise (H’ Higher = 1.80; Middle = 2.07; Lower = 1.95) or month-wise (H’ Dec ’16 = 2.36; Jan ’17 = 2.46; Feb ’17 = 2.32). Nevertheless, there is evidence showing that existence of species specificity towards altitude especially on the higher altitude which only one species that shared with middle altitude (Galerucinae sp. 1), while middle and lower shared more overlapped species. More intensive study must be done to view the distribution pattern more clear and detailed

New species of the genus Tabanus linnaeus, 1758 (diptera: tabanidae) from Malaysia

Tabanids are true flies, with medical and veterinary importance. In the current report, a new species; Tabanus zuhairi sp. nov. is described. Main taxonomic characters including antennae, frons, and palpi are illustrated. The new species is recognized based on the cross-band of the wing and shiny subcallus

Effects of gamma irradiation on egg hatchability, pupation, and adult emergence of the immature stages of the oriental fruit fly, Bactrocera dorsalis (hendel) (diptera: tephritidae) from Malaysia

Studies on the effect of irradiation on egg hatchability, pupation and adult emergence of the immature stages of the Oriental Fruit Fly, Bactrocera dorsalis (Hendel) was conducted in Malaysian Nuclear Agency, Dengkil, Selangor, Malaysia using a Co-60 source. Eggs, 1st instars to 3rd instars larvae and pupae stages were treated separately with dosages 50Gy to 400Gy to determine the most tolerance stage and the optimum dose for provide quarantine security. Each treatment involves a minimum of 100 individuals for each dose with four replications. The hatch from eggs to 1st instar larvae, pupation from eggs and all of three instars larvae to pupae, and eclosion from pupae to adult, were used as criteria to determine the effect of irradiation. Egg hatch was completely inhibited by 100Gy for early egg and 300Gy for late eggs. Dose of 200Gy and 250Gy were able to prevent completely pupation when treated from egg stage and 1st instar larvae, respectively. Unfortunately, those dosages did not affect pupation when applied to 2nd and 3rd instars, but it did prevent any from emerging as adults. Adult emergence was 100% prevented when eggs and all larvae were treated at 100Gy as compared to pupae was not completely prevented even by 400Gy. Among the four immature stages of B. dorsalis, the 3rd instar larvae (inside fruits) and pupae (outside fruits) were found to be the most tolerance stage and the early eggs are the most susceptible stage to irradiation. Our results suggest that minimum dose 100 to 150Gy is sufficient to provide a high level of quarantine security against this important pest and the dose might allow for irradiation be accepted as a quarantine treatment for most tropical fruits from Malaysia

Distribution of serotonin (5-HT) and dopamine (DA) on digestive tract of red palm weevil larva, Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae)

The red palm weevil (RPW), Rhynchophorus ferrugineus (Coleoptera: Dryopthoridae) is a well-known deadly pest of palmae tree worldwide. The larvae of RPW is the most destructive stage of its life cycle and caused great economic lost to palm tree plantation for example the coconut tree plantations. In this study, we focused on detection of two important biogenic amines, serotonin (5-HT) and dopamine (DA) that play important roles in the regulation of the digestive tract of this insect. Immunohistochemistry analysis has been carried out on the cross-sectioned tissue of three different parts of the digestive tract; foregut, midgut and hindgut. 5-HT receptor for serotonin and D1 receptor for dopamine were chosen for chromogenic detection of the biogenic amine. The distribution of 5-HT can be detected at the plasma membrane, basement membrane and cytoplasm of the cell for the whole guts except at the midgut cell. While DA can only be detected at the basal membrane of the gut cell for the most part of the gut. Further study could be done to find a possible solution in controlling the survival of RPW by understanding the roles of the biogenic amine in controlling and modulating the mechanism of absorption and digestion of the digestive tract

Morphology and histology of reproductive organ and first screening of wolbachia in the ovary of red palm weevil, Rhynchophorus ferrugineus (coleoptera: dryophthoridae)

This study was conducted to assess intracellular bacteria Wolbachia in the ovaries of female Red Palm Weevil (RPW), Rhynchophorus ferrugineus from three populations in Malaysia by means of PCR using wsp- specific primer. The morphology and histology of ovary of RPW were also studied and examined by stereo microscope LEICA EZ4 HD that was equipped with LAS EZ software and light microscope Zeiss Axio Scope with iSolutionLite software respectively. We found that the adult female had two pairs of ovaries, lateral oviduct, common oviduct, bursa copulatrix, spermatheca and vagina. Histological study of the ovariole revealed that it is categorised under polytrophic ovariole. The ovariole is divided into four regions, the terminal filament, the germarium, the vitellarium and the stalk or calyx. Besides, the infection status showed that all three populations were not infected with Wolbachia. Our result suggests that no infection of Wolbachia in RPW reproductive system

Characterization of the mechanism of prolonged adaptation to osmotic stress of Jeotgalibacillus malaysiensis via genome and transcriptome sequencing analyses

Jeotgalibacillus malaysiensis, a moderate halophilic bacterium isolated from a pelagic area, can endure higher concentrations of sodium chloride (NaCl) than other Jeotgalibacillus type strains. In this study, we therefore chose to sequence and assemble the entire J. malaysiensis genome. This is the first report to provide a detailed analysis of the genomic features of J. malaysiensis, and to perform genetic comparisons between this microorganism and other halophiles. J. malaysiensis encodes a native megaplasmid (pJeoMA), which is greater than 600 kilobases in size, that is absent from other sequenced species of Jeotgalibacillus. Subsequently, RNA-Seq-based transcriptome analysis was utilised to examine adaptations of J. malaysiensis to osmotic stress. Specifically, the eggNOG (evolutionary genealogy of genes: Non-supervised Orthologous Groups) and KEGG (Kyoto Encyclopaedia of Genes and Genomes) databases were used to elucidate the overall effects of osmotic stress on the organism. Generally, saline stress significantly affected carbohydrate, energy, and amino acid metabolism, as well as fatty acid biosynthesis. Our findings also indicate that J. malaysiensis adopted a combination of approaches, including the uptake or synthesis of osmoprotectants, for surviving salt stress. Among these, proline synthesis appeared to be the preferred method for withstanding prolonged osmotic stress in J. malaysiensis