Biology of Tiger Moth (Atteva Sciodoxa Meyrick) Infesting Tongkat Ali (Eurycoma Longifolia Jack) and its Control by Beauveria Bassiana

Eurycoma longifolia is a widely used medicinal plant in South East Asia. Atteva sciodoxa, the small golden brown moth, became serious pest with the onset of E. longifolia plantations. The widespread medicinal use of E. longifolia and deleterious effects of chemical insecticides led to search non-chemical control of A. sciodoxa. The research was undertaken to study some biological aspects of A. sciodoxa and to assess potential of entomopathogenic fungus Beauveria bassiana to control A. sciodoxa. A. sciodoxa feeds gregariously by building communal webs on the terminal shoots. The infestation ranged between 65.0±2.03% and 92.6±1.13%. A. sciodoxa completed its five larval instars in 20.7±0.2 days while lifecycle duration in 46.3±0.49 days. The population rate of increase ranged between 0.33 and 1.39 female off springs per female. The net reproductive rate, mean generation time and population doubling time were 42.03 female offsprings per female, 11.41 days and 2.12 days respectively. The highest apparent, real and indispensable mortality were in first instar larvae. The lower threshold temperature was between 9.2°C and 14.7°C while the thermal constant ranged from 126.4 to 79.3 degree-days for different metamorphic stages. The mean food ingestibility, efficiency of conversion of ingested food, efficiency of conversion of digested food and approximate digestibility were 75.2±0.32%, 67.8±0.74%, 37.0±1.21% and 63.10.73%, respectively. The mean food consumption index was 0.23 mg dry leaf per mg larval body weight per day while relative growth rate was 0.08 mg body larval weight gain per mg larval body weight per day. Seven B. bassiana isolates obtained from different sources were screened for pathogenicity. All the isolates were found to be pathogenic. The degree of pathogenicity varied significantly among the isolates. The earliest mortality was recorded on day three after inoculation in five isolates. The most virulent isolate was Bba-Pp with 100% mortality and median effective time of 3.6 days. The least infective isolate was Bba-Sl3 with 24.9±2.10% mortality and the median effective time of 15.3 days. The median effective concentration was 9.89x105 and 3.85x106 conidia ml-1 for Bba-Pp and FS-11, respectively. Mycosis time differed significantly among isolates. Isolate Bba-Pp appeared earliest on cadavers in 24 h. The conidial production ranged between 1.2±0.84x106 and 1.5±3.30x107 conidia per mg cadaver in the seven tested isolates. Isolate Bba-Pp decreased food consumption by 72.5% at concentration of 1x107 conidia ml-1 as compared to the control. The age specific dose mortality response revealed high infectivity of B. bassiana Bba-Pp in all metamorphic stages of A. sciodoxa. The highest egg infectivity was 22.6±1.60% when 24 h-old eggs were inoculated at 1x108 conidia ml-1 while the highest delayed first instar larval mortality was 85.6±2.30% when eggs were inoculated at 24 h before hatching at 1x108 conidia ml-1. The third instar larva was most susceptible while the fifth instar larva was the least. The median effective concentration ranged between 9.87x105 and 21.3x105 conidia ml-1 for third to fifth instar larvae while the median effective time ranged from 3.3 to 8.2 days for three tested larval instars at different concentrations. There was a significant temperature effect on B. bassiana Bba-Pp infectivity with optimum range between 27°C and 30°C. Infectivity, mycosis and sporulation were strongly affected when larva, leaf, or both, were inoculated by B. bassiana Bba-Pp. Larval mortality ranged between 38.1±3.21% and 94.6±2.40% in three exposure methods. Larval mortality of 54.1±1.74% was recorded due to secondary acquisition of conidia from spray residues on the foliage of E. longifolia. The shortest mean mycosis time was 20.2±0.37 h when both larvae and leaves were inoculated and cadavers incubated at 30°C while the longest was 28.0±0.45 h when only leaves were inoculated and cadavers incubated at 21°C. The highest conidial production was 150.9±0.01x105 conidia per mg cadaver when both larvae and leaves were inoculated at a concentration of 1x108 conidia ml-1 and cadavers incubated at 27ºC. The lowest conidial production was 46.6±0.02x105 conidia per mg cadaver when only leaves were inoculated at a concentration of 1x107 conidia ml-1 and cadavers incubated at 33°C. The highest conidial germination and the longest germ tube length was 99.2±0.37% and 45.6±0.84 μm at 27ºC, respectively. The optimum temperature for mycosis, sporulation, conidial germination and germ tube growth rate was between 27ºC and 30ºC. B. bassiana Bba-Pp was transmitted horizontally from exposed to unexposed larvae, via infective cadavers and contaminated faeces. The highest net transmitted mortality was 87.5±1.17% when exposed larvae were inoculated at 1x108 conidia ml-1 and mixed with same number of unexposed larvae. There was significant effect of concentration and ratio on net transmitted mortality. The highest transmitted mortality via infective cadaver was 92.1±1.31% at a density of 0.12 cadaver cm-2. Viable B. bassiana Bba-Pp was isolated from faeces when larvae were inoculated by different exposure methods and at different concentrations. The highest number of B. bassiana Bba-Pp colonies isolated was 15.5±0.12x103 per mg faeces isolated on day one following inoculation of both larvae and leaves at concentration of 1x108 conidia ml-1. The number of B. bassiana colonies was influenced by exposure method, concentration and the time following inoculation. Larval mortality of 42.2±1.36% was caused when larvae exposed to faeces with 15.5±0.12x103 B. bassiana colonies per mg. The findings biological studies indicated that A. sciodoxa has characteristics of a serious pest. The results also showed high infectivity, residual effect, horizontal transmission and recycling capacity of B. bassiana in A. sciodoxa. Based on these findings it is concluded that B. bassiana Bba-Pp has potential to control A. sciodoxa

Pathogenicity of Beauveria bassiana against the tiger moth Atteva sciodoxa (Lepidoptera: Yponomeutidae)

Seven isolates of Beauveria bassiona were screened for pathogenicity and infectivity at a concentration of 5x107 conidia mL-1 against Attevo sciodoxa at 27±2°C and 75±5% relative humidity with 12 h photoperiod. Based on screening results, isolates Bba-Pp and FS-11 were further bioassayed at 1 x 106, 5x106 and 1x107 conidia mL-1. All the isolates were found to be pathogenic. However, the infectivity varied significantly among the isolates. The earliest mortality was recorded three days after inoculation, The most virulent isolate, Bba-Pp, caused 100% mortality with a median infective time (ET50) of 3.6 days on day seven following inoculation while FS-11 caused 83,3% mortality with an ET50 value of 4.1 days, Bba-S13 was the least infective isolate with 24.9% mortality and 15.3 days of median effective time. Mycelia appeared on 24 to 48 h old cadavers, The highest level of sporulation on two-week old cadavers was 150.6x105 Bba-Pp conidia mg -1 cadaver while the lowest was 12.23x105 Bba-S13 conidia. The median effective concentration (EC50) of Bba-Pp was 9.89x105 conidia mL-1 while that of FS-11 was 3.85x106 conidia mL-1. The ET50 values 1x106 1x107 conidia mL-1 of Bba-Pp ranged between 7.0 and 4.4 days, respectively, while that of FS-11 were 10.3 and 5.8 days. A strong negative correlation was found between inoculum concentrations and food consumption (R2 = -0.99). The infection by Bba-Pp and FS-11I resulted in 55.8 to 72.5% reduction in food consumption by A. sciodoxa compared to the controls

Life table and demographic parameters of the tiger moth, Atteva sciodoxa Meyrick (Lepidoptera: Yponomeutidae) fed on Eurycoma longifolia Jack.

Age-specific life and fertility tables of the tiger moth, Atteva sciodoxa Meyrick were constructed under controlled environmental conditions. The highest apparent mortality (qx), real mortality (RM) and indispensable mortality (IM) values were recorded in the 1st instar larvae whilst the lowest in the fifth instar larvae. The longest lifespan of female moth was 19 days with 50% natural mortality (NM50) on day 15 and that of male was 16 days with NM50 on day 11. The mean number of eggs female-1 was 106.2 and oviposition period was 13.3 days. Values for the net reproductive rate (RO), mean generation time (TC), intrinsic rate of increase (rc), innate capacity of increase (rm), finite rate of increase (λ) and doubling time (DT) were 42.03 female offsprings female-1, 11.41 days, 0.33 day-1, 0.37 day-1, 1.39 female offsprings female-1 day-1 and 2.12 days, respectively

A review of insect defoliators on teak with special reference to Paliga damastesalis Walker in Malaysia

Teak is a deciduous hardwood tree species native to India, Bangladesh, Myanmar, the Lao People's Democratic Republic, Thailand, Vietnam and Cambodia. It is renowned for its aesthetic qualities, durability and versatility for a wide range of uses including furniture manufacture, ship building, decorative panelling and flooring. However, the tree is predisposed to a spectrum of insect pests particularly when grown as a monoculture or mked plantation crop. More than 285 insect pests have been reported globally on teak. Of these, defoliators rank highest in the damage caused to teak saplings and plantations, worldwide. These primarily belong to three orders' namely Lepidoptera (139), Coleoptera (41) and Orthoptera (18). In Malaysia, 28 insect pests have been reported thus far. Among these, Paliga damastesalis Walker (Lepidoptera: Crambidae), Xyleutes ceramica Walker (Lepidoptera: Cossidae) and Hyblaea puera Cramer (Lepidoptera: Hyblaeidae) are common pests, with P. damastesalis as the major defoliator in Malaysia. The effects of defoliation is especially severe in young plantations. Although outbreaks are predominantly seasonal and has been frequently associated with flushing of leaves, the insect remains active throughout the year, with a total of 12 to 13 overlapping generations per year

Developmental biology of the tiger moth, Atteva sciodoxa Meyrick (Lepidoptera: Yponomeutidae) under laboratory conditions

The tiger moth, Atteva sciodoxa is a serious pest of tongkat Ali, Eurycoma longifolia. The morphology, development times and fecundity aspects were studied at 27±2°C, 90±5% relative humidity and 12 h photoperiod. The eggs were yellow and ovoid in shape with a mean length and width of 1.19±0.02 and 0.86±0.02 mm, respectively. Width measurements of larval head capsules showed that A. sciodoxa undergoes five larval instar stages. The mean head capsule widths of the first to fifth instar larvae were 0.55±0.01, 0.89±0.01, 1.23±0.02, 1.52±0.01 and 2.11±0.02 mm, while the body lengths were 4.71±0.1, 8.63±0.1, 12.87±0.1, 16.29±0.1 and 21.74±0.2 mm, respectively. The mean male and female pupal body lengths were 10.36±0.1 and 11.26±0.2 mm, respectively. The mean male and female wing span were 21.63±0.2 and 24.28±0.2 mm, respectively. The mean pre-oviposition and oviposition periods were 6.2±0.23 and 8.5±0.28 days, respectively. A single female laid on average 106.1±4.85 eggs with maximum production between days 8-15 of adult emergence. The maximum number of eggs laid per female per day was 20.1±0.5. The mean hatching time was 5.7±0.1 days with a mean hatchability of 81.1±0.6%. The mean larval, pupal and adult periods were 20.7±0.2, 6.2±0.8 and 13.2±0.5 days, respectively. The female pupal period and adult lifespan were significantly longer than the male. Atteva sciodoxa completed its life cycle in 46.28±0.49 days

The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy

Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations. Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves. Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p  90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score. Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care

Eco-biology, impact, and management of Sorghum halepense (L.) Pers

Sorghum halepense (L.) Pers. is ranked among the worst and extensively disseminated weed species. It is emerging as a potential menace for agroecosystems in 53 different countries across the world. This weed is adapted to warmer regions and is native to Mediterranean areas of Africa, Asia, and Europe. In the mid-1900s, cultivation of this weed species as a potential forage crop resulted in its escape from crop fields and invasion of agricultural and natural areas, but in some European countries, it has been introduced deliberately (e.g., as contamination of seeds and soil). S. halepense interferes with economically important agronomic and horticultural crops and cause 57–88% yield losses. Herbicide tolerance, diverse propagation mechanisms, rapid development, and strong competitiveness are key attributes in its invasion. Conventional management approaches are limited in their scope to control this weed due to its rapid vegetative growth and increasing herbicidal tolerance. Integration of chemical methods with cultural or mechanical approaches is important for restricting its future spread to non-infested areas. This review provides insights into the invasion mechanisms of S. halepense, which will help in its management. A better understanding of ecobiological aspects, survival mechanisms, and genetic variabilities of S. halepense, within a wide range of environmental conditions, will assist in designing more effective management strategies for this serious invasive weed. Collaborative research between the various countries impacted by this weed will assist in developing efficient, sustainable, and economical approaches to restrict its invasion in new areas

Eco-biology, impact, and management of Sorghum halepense (L.) Pers

Sorghum halepense (L.) Pers. is ranked among the worst and extensively disseminated weed species. It is emerging as a potential menace for agroecosystems in 53 different countries across the world. This weed is adapted to warmer regions and is native to Mediterranean areas of Africa, Asia, and Europe. In the mid-1900s, cultivation of this weed species as a potential forage crop resulted in its escape from crop fields and invasion of agricultural and natural areas, but in some European countries, it has been introduced deliberately (e.g., as contamination of seeds and soil). S. halepense interferes with economically important agronomic and horticultural crops and cause 57–88% yield losses. Herbicide tolerance, diverse propagation mechanisms, rapid development, and strong competitiveness are key attributes in its invasion. Conventional management approaches are limited in their scope to control this weed due to its rapid vegetative growth and increasing herbicidal tolerance. Integration of chemical methods with cultural or mechanical approaches is important for restricting its future spread to non-infested areas. This review provides insights into the invasion mechanisms of S. halepense, which will help in its management. A better understanding of ecobiological aspects, survival mechanisms, and genetic variabilities of S. halepense, within a wide range of environmental conditions, will assist in designing more effective management strategies for this serious invasive weed. Collaborative research between the various countries impacted by this weed will assist in developing efficient, sustainable, and economical approaches to restrict its invasion in new areas

Enhanced Degradation of Ciprofloxacin in Floating Treatment Wetlands Augmented with Bacterial Cells Immobilized on Iron Oxide Nanoparticles

Antibiotic contamination of water is an emerging global issue with severe implications for both public health and the environment. Ciprofloxacin (CIP) is a synthetic fluoroquinolone antibiotic, which is broadly used in human and veterinary medicines around the world to treat various bacterial infections. The presence of CIP in the aquatic environment poses serious health problems to human beings and other living entities. Floating treatment wetland (FTW) is a low-cost and eco-friendly wastewater remediation technology. In the current study, the Canna indica. (Indian shot) was vegetated in a floatable mat to develop FTWs. A consortium of three bacterial strains, Acinetobacter lwoffii ACRH76, Bacillus pumulis C2A1, and Acinetobacter sp. HN3, was immobilized on iron oxide nanoparticles (Fe3O4-NPs) and augmented in the FTWs for the remediation of CIP-contaminated (100 mg/L) water. The augmentation of bacteria (immobilized or free) in the FTWs significantly enhanced the removal of CIP from water. The maximum reduction in CIP (98%), chemical oxygen demand (COD; 90%), biochemical oxygen demand (BOD; 93%) and total organic carbon (TOC; 95%) was observed in FTWs that had Fe3O4-NP supported bacteria. This study reveals that FTWs have a great potential to remove the CIP from contaminated water, albeit its CIP removal efficiency was substantially enhanced by augmentation with Fe3O4-NPs supported bacteria

Enhanced Degradation of Ciprofloxacin in Floating Treatment Wetlands Augmented with Bacterial Cells Immobilized on Iron Oxide Nanoparticles

Antibiotic contamination of water is an emerging global issue with severe implications for both public health and the environment. Ciprofloxacin (CIP) is a synthetic fluoroquinolone antibiotic, which is broadly used in human and veterinary medicines around the world to treat various bacterial infections. The presence of CIP in the aquatic environment poses serious health problems to human beings and other living entities. Floating treatment wetland (FTW) is a low-cost and eco-friendly wastewater remediation technology. In the current study, the Canna indica. (Indian shot) was vegetated in a floatable mat to develop FTWs. A consortium of three bacterial strains, Acinetobacter lwoffii ACRH76, Bacillus pumulis C2A1, and Acinetobacter sp. HN3, was immobilized on iron oxide nanoparticles (Fe3O4-NPs) and augmented in the FTWs for the remediation of CIP-contaminated (100 mg/L) water. The augmentation of bacteria (immobilized or free) in the FTWs significantly enhanced the removal of CIP from water. The maximum reduction in CIP (98%), chemical oxygen demand (COD; 90%), biochemical oxygen demand (BOD; 93%) and total organic carbon (TOC; 95%) was observed in FTWs that had Fe3O4-NP supported bacteria. This study reveals that FTWs have a great potential to remove the CIP from contaminated water, albeit its CIP removal efficiency was substantially enhanced by augmentation with Fe3O4-NPs supported bacteria