Diurnal attraction of fruit flies (diptera: tephritidae) to methyl eugenol in a village ecosystem in Tanjung Bungah, Penang, Malaysia

Diurnal rhythm of male Bactrocera fruit fly attraction to methyl eugenol (ME) was investigated using clear traps design in a village ecosystem in Tanjung Bungah, Penang, Malaysia. The diurnal rhythm pattern studied by half-hourly sampling from 07:00 to 18:00 hr showed significant male fruit fly attraction to ME in the morning from 07:30 to 09:30 hr, with a distinct peak at 08:30-09:00 hr. The male attraction to ME was significantly lower in the afternoon and remained low approaching late afternoon. The ME-responding fruit fly species captured were B. dorsalis (86%), which dominated the local Bactrocera community, followed by B. umbrosa (5.8%) and B. carambolae (0.1%). This showed that B. dorsalis is a more dominant species than its sibling species, B. carambolae in the area studied. In addition, ca. 8.1% of Bactrocera male flies that bore intermediate morphological characteristics between B. dorsalis and B. carambolae were also captured in those traps. The present study shows that for ME-responding Bactrocera spp., male attraction to ME occurs throughout the day with peak period of attraction to ME occurring ca. 30 mins following sunrise for 2 hrs before gradually tapering off

Attraction and consumption of methyl eugenol by male Bactrocera umbrosa Fabricius (Diptera: Tephritidae) promotes conspecific sexual communication and mating performance

The Artocarpus fruit fly, Bactrocera umbrosa (Fabricius) (Diptera: Tephritidae), is an oligophagous fruit pest infesting Moraceae fruits, including jackfruit (Artocarpus heterophyllus Lamarck), a fruit commodity of high value in Malaysia. The scarcity of fundamental biological, physiological and ecological information on this pest, particularly in relation to behavioural response to phytochemical lures, which are instrumental to the success of many area-wide fruit fly control and management programmes, underpins the need for studies on this much-underrated pest. The positive response of B. umbrosa males to methyl eugenol (ME), a highly potent phytochemical lure, which attracts mainly males of many Bactrocera species, was shown to increase with increasing age. As early as 7 days after emergence (DAE), ca. 22% of males had responded to ME and over 50% by 10 DAE, despite no occurrence of matings (i.e. the males were still sexually immature). Male attraction to ME peaked from 10 to 27 DAE, which corresponded with the flies’ attainment of sexual maturity. In wind-tunnel assays during the dusk courtship period, ME-fed males exhibited earlier calling activity and attracted a significantly higher percentage of virgin females compared with ME-deprived males. ME-fed males enjoyed a higher mating success than ME-deprived males at 1-day post ME feeding in semi-field assays. ME consumption also promotes aggregation behaviour in B. umbrosa males, as demonstrated in wind-tunnel and semi-field assays. We suggest that ME plays a prominent role in promoting sexual communication and enhancing mating performance of the Artocarpus fruit fly, a finding that is congruent with previous reports on the consequences of ME acquisition by other economically important Bactrocera species

Phenylpropanoid sex pheromone component in hemolymph of male Carambola fruit fly, Bactrocera carambolae (Diptera: Tephritidae)

Males of the Carambola fruit fly, Bactrocera carambolae Drew & Hancock (Diptera: Tephritidae) are strongly attracted to, and feed on methyl eugenol (ME) that exists as a plant secondary compound in over 480 plant species worldwide. Upon feeding on this highly potent attractant, the males convert ME into a phenylpropanoid, (E)-coniferyl alcohol (ECF), that is stored in the rectal gland prior to its release as a sex pheromone component during calling and courtship. Here, using a series of chemical and behavioural assays, we provide evidence for the presence of ECF in the hemolymph and suggest the latter’s involvement in transport of ECF to the male rectal gland following consumption of ME. The greatest concentration of ECF was detected in the hemolymph at 3 h after feeding on ME and subsequently decreased, whereas accumulation of ECF in the rectal gland reached a maximum at 2 days post-feeding. Using male flies as biodetectors, fractions of 1.5–9.2 kDa from fractionated hemolymph of ME-fed males were found to be attractive and contained ECF as sex pheromone. In addition, the significant increase in the total concentration of protein in hemolymph from ME-fed males compared with that of ME-deprived males suggests a direct protein carrier involvement in hemolymph transport of the sex pheromone in B. carambolae. All these results are further discussed in comparison with previous results obtained from its sibling species, the Oriental fruit fly—B. dorsalis

Cytogenetic, chromosome count optimization and automation of Neolamarckia cadamba (Rubiaceae) root tips derived from in vitro mutagenesis

Chromosome count is the only direct way to determine the number of chromosomes of a species. This study is often considered trivial that seldom described and discussed in detail. Therefore, it is inevitable that the chromosome count protocol should be revised and revisited before it becomes obliterated. In the present study, we encountered challenges in obtaining a clear micrograph for the chromosome count of active mitotic cells of Neolamarckia cadamba (Roxb.) Bosser (Rubiaceae) root tips. Several obstacles were determined through micrograph observation, such as existing unwanted particles in cells, poor chromosome staining and chromosome clumping. To overcome these, root tip types, staining methodologies, squashing methods were among the factors assessed to obtain clear micrographs. The chromosome counts of N. cadamba under optimized procedure showed 2n = 44 chromosomes. We also apply digital technology in chromosome counts, such as online databases and graphic software that are open source and freely accessible to the public. Only basic laboratory equipment and chemicals were used throughout the study, thus making this study economical and applicable in a basic laboratory. The availability of online digital software and databases provide open-source platforms that will ease the efforts in chromosome count

Molecular Cloning of Hypervariable Regions (HVRII) from Cellulose Synthase (CesA) Gene in Neolamarckia cadamba

Neolamarckia cadamba or locally known as Kelampayan, is one of the fast growing plantation tree species that holds great prospect as a renewable bioresources for plywood, pulp and paper, and biofuel industries. Sufficient information on cellulose synthase (CesA) gene, especially the hypervariable region II (HVRII) component involved in wood formation of Kelampayan is imperative for future applications. This region is thought to play a role in interaction with other unique cell-type-specific proteins involved in the biosynthesis of cellulose. The aim of this study was to identify and clone the HVRII regions of cellulose synthase gene from the developing xylem tissues of Kelampayan. The cDNA of cellulose synthase HVRII regions was amplified using reverse transcription-PCR (RT-PCR) approach using degenerate primers. Three clones, namely NcCesA1HVRII (520bp), NcCesA2HVRII (580bp) and NcCesA3HVRII (620bp) were successfully sequenced and characterized. NcCesA1HVRII and NcCesA3HVRII were clustered into two distinct clades implicated with secondary cell wall development whereas NcCesA2HVRII has renamed to NcCslD1HVRII due its high similarity with various plants’ CslD-HVRII. This study provides an easier and faster access to NcCesAHVRII sequences to further understand the role of NcCesA/NcCslD protein for future applications such as selecting trees with optimal cellulose content required for specific industries

Comparative sensitivity to methyl eugenol of four putative Bactrocera dorsalis complex sibling species-further evidence that they belong to one and the same species B. dorsalis

Males of certain species belonging to the Bactrocera dorsalis complex are strongly attracted to, and readily feed on methyl eugenol (ME), a plant secondary compound that is found in over 480 plant species worldwide. Amongst those species is one of the world’s most severe fruit pests the Oriental fruit fly, Bactrocera dorsalis s.s., and the former taxonomic species Bactrocera invadens, Bactrocera papayae and Bactrocera philippinensis. The latter species have been recently synonymised with Bactrocera dorsalis based on their very similar morphology, mating compatibility, molecular genetics and identical sex pheromones following consumption of ME. Previous studies have shown that male fruit fly responsiveness to lures is a unique phenomenon that is dose species-specific, besides showing a close correlation to sexual maturity attainment. This led us to use ME sensitivity as a behavioural parameter to test if Bactrocera dorsalis and the three former taxonomic species had similar sensitivity towards odours of ME. Using Probit analysis, we estimated the median dose of ME required to elicit species’ positive response in 50% of each population tested (ED50). ED50 values were compared between Bactrocera dorsalis and the former species. Our results showed no significant differences between Bactrocera dorsalis s.s., and the former Bactrocera invadens, Bactrocera papaya and Bactrocera philippinensis in their response to ME.We consider that the Bactrocera males’ sensitivity to ME may be a useful behavioural parameter for species delimitation and, in addition to other integrative taxonomic tools used, provides further supportive evidence that the four taxa belong to one and the same biological species, Bactrocera dorsalis

Recommendation for a contouring method and atlas of organs at risk in nasopharyngeal carcinoma patients receiving intensity-modulated radiotherapy

Background and purpose To recommend contouring methods and atlas of organs at risk (OARs) for nasopharyngeal carcinoma (NPC) patients receiving intensity-modulated radiotherapy, in order to help reach a consensus on interpretations of OARs delineation. Methods and materials Two to four contouring methods for the middle ear, inner ear, temporal lobe, parotid gland and spinal cord were identified via systematic literature review; their volumes and dosimetric parameters were compared in 41 patients. Areas under the receiver operating characteristic curves for temporal lobe contouring were compared in 21 patients with unilateral temporal lobe necrosis (TLN). Results Various contouring methods for the temporal lobe, middle ear, inner ear, parotid gland and spinal cord lead to different volumes and dosimetric parameters (P < 0.05). For TLN, D1 of PRV was the most relevant dosimetric parameter and 64 Gy was the critical point. We suggest contouring for the temporal lobe, middle ear, inner ear, parotid gland and spinal cord. A CT-MRI fusion atlas comprising 33 OARs was developed. Conclusions Different dosimetric parameters may hinder the dosimetric research. The present recommendation and atlas, may help reach a consensus on subjective interpretation of OARs delineation to reduce inter-institutional differences in NPC patients. © 2013 Elsevier Ireland Ltd. All rights reserved.published_or_final_versio

RNA Viral Community in Human Feces: Prevalence of Plant Pathogenic Viruses

The human gut is known to be a reservoir of a wide variety of microbes, including viruses. Many RNA viruses are known to be associated with gastroenteritis; however, the enteric RNA viral community present in healthy humans has not been described. Here, we present a comparative metagenomic analysis of the RNA viruses found in three fecal samples from two healthy human individuals. For this study, uncultured viruses were concentrated by tangential flow filtration, and viral RNA was extracted and cloned into shotgun viral cDNA libraries for sequencing analysis. The vast majority of the 36,769 viral sequences obtained were similar to plant pathogenic RNA viruses. The most abundant fecal virus in this study was pepper mild mottle virus (PMMV), which was found in high concentrations—up to 10(9) virions per gram of dry weight fecal matter. PMMV was also detected in 12 (66.7%) of 18 fecal samples collected from healthy individuals on two continents, indicating that this plant virus is prevalent in the human population. A number of pepper-based foods tested positive for PMMV, suggesting dietary origins for this virus. Intriguingly, the fecal PMMV was infectious to host plants, suggesting that humans might act as a vehicle for the dissemination of certain plant viruses

Validation of the Children’s Eating Behavior Questionnaire in 5 and 6 Year-Old Children: The GUSTO Cohort Study

Revised subscales of the Children’s Eating Behavior Questionnaire (CEBQ) have been proposed to be more appropriate for assessing appetitive traits in Singaporean 3 year-olds, but the CEBQ has not yet been validated in older children in this population. The current study aimed to validate the CEBQ at ages 5 (n = 653) and 6 (n = 449) in the ethnically diverse GUSTO cohort. Confirmatory factor analysis (CFA) examined whether the established eight-factor model of the CEBQ was supported in this sample. Overall, the CFA showed a poor model fit at both ages 5 and 6. At both ages 5 and 6, an exploratory factor analysis revealed a six-factor structure: food fussiness, enjoyment of food, slowness in eating, emotional undereating, emotional overeating and desire to drink. Cronbach’s alpha estimates ranged from 0.70 to 0.85 for all subscales. Criterion validity was tested by correlating subscales with the weight status of 6 years of age. At age 5 and 6, lower scores of slowness of eating while higher scores of enjoyment of food was associated with child overweight. At age 6, higher scores of desire to drink was also associated child overweight. In conclusion, a revised six factor-structure of the CEBQ at ages 5 and 6 were more appropriate for examining appetitive traits in this sample