Population genetic structure of Culex quinquefasciatus in India by ISSR marker

Objective:To characterize the genetic structure of various populations of Culex quinquefasciatus (Cx.quinquefasciatus) from India representing different geoclimatic locations.Methods:Inter simple sequence repeat(ISSR) markers were used.A set of 20 primers were screened with the laboratory populations of mosquito species.Finally the IS 40 primer was chosen based on the scorable banding pattern showing 100 percent polymorphism among the various populations.The statistical analysis was done using POPGENE 1.31 software.The consensus tree was generated based on UPGMA modified from NEIGHBOR procedure of PHYLIP Version 3.5.Results:The cluster analysis shows the main cluster which is divided into two sub cluster representing all the populations separated as per their phylogeographic and geoclimatic condition.Conclusions: The findings will be helpful in understanding the population variation under different ecological conditions and development of effective vector management strategies.

中国大平叩甲属一新种及种检索表(鞘翅目:叩甲科:齿胸叩甲亚科)（英文）

记述中国凹缘大平叩甲Ohirathous emarginatus sp. nov.,提供了形态特征图以及种检索表和名录及分布图。

Status and Constrain for Mechanization of Rice Harvesting System in Bangladesh

To know the position, problems and suggestion of harvest mechanization of rice, the study conducted in 21 upzillas under seven regions (Dhaka, Mymensingh, Sylhet, Comilla, Bogra, Rajshahi and Rangpur) based on different agro-climatic condition and cropping intensity and 126 farmers participated in the interview. For collecting data, a structured questionnaire was used and statistical analysis of the collected data was carried out. In study area, the average cultivable area was 225 to 1239 decimal (1 decimal = 40 m2) and 97.60% farmer reaping by sickle and only 0.80% used combine harvester. Cut paddy transported by head (13.49%), shoulders (12.7%) or both of them of 11.11% farmer and 44.44% of farmers used small truck or field threshed. Threshing was mainly done using (49.21%) closed drum thresher and open drum thresher (26.20%), likewise 1 of 126 farmer use head-feed combine harvester. The study area, most farmers (37.3%) used kula for the cleaning of rice, but only 8.74% of farmers used winnower. In considerable amount, 80.95% of farmers had machinery, while the remaining (19.05%) did not have machines. Farmers agreed that harvesting was a labor-intensive method (35.71%) and time consuming (28.57%). Transporting of harvested paddy was dangerous and painful for head, shoulder, hand, waist, backbone, leg, etc. With mechanization and the introduction of machinery, 40.48% of farmers identified the main ceiling as the price of the machine and information/lack of credit system (21.43%). In survey area, most farmers (36.51%) identified the vital advantage of mechanized harvesting as lower labor requirement, while 21.43% of farmers said that a lower loss of rice. All farmers who participated in the interview expressed their need for machinery and mentioned agricultural credit with easy terms and conditions, subsidy for buying machinery and the ensuring of a fair market price for their rice.

Evaluation of different formulations of IGRs against Aedes albopictus and Culex quinquefasciatus(Diptera:Culicidae)

Objective: To test the relative efficacy of pyriproxyfen and methoprene on mortality,deformity, inhibition and emergence to adult stages of Culex quinquefasciatus and Aedes albopictus.Methods: Serial dilutions(0.01–0.05 mg/L) of methoprene, pyriproxyfen 0.5 water dispersible granules(WDG) and pyriproxyfen 1.0 WDG were used to assess mortality and inhibition of 3rd instar larvae of Aedes albopictus and Culex quinquefasciatus. Each concentration and control was replicated four times in completely randomized design.Data on larval mortality, growth inhibition, deformities and adult's emergence was recorded weekly. On the basis of best comparative performance, the efficacy of pyriproxyfen 1.0 WDG at 0.1 g/m3 was also tested in the field by collecting treated water samples monthly for 1–6 months after field application. Twenty five 3rd instar larvae of Aedes and Culex spp. of the same cohorts were used for bioassays and compared with larvae in control cups containing 1 L of untreated tap water.Results: Results revealed variations in fatality of different insect growth regulators(IGRs) to the 3rd instar larvae of Culex and Aedes mosquitoes. Among the IGRs, pyriproxyfen 1.0 WDG was found best that exhibited significantly high emergence inhibition against Culex and Aedes spp. Based on the results, the IGRs were classified in terms of the tested parameters in order of pyriproxyfen 1.0 WDG > pyriproxyfen 0.5WDG > methoprene. In case of field studies, pyriproxyfen 1.0 WDG, pool data of the entire target treated sites showed minimum adult emergence from water sampled of habitats treated with 0.1 g/m3 of pyriproxyfen 1.0 WDG.Conclusions: It is thus concluded that IGRs can be utilized as environment friendly control measures for Culex and Aedes spp. of mosquitoes on small and large scale. This will reduce the use of conventional insecticides by the public health authorities and help in reducing selection pressure of insecticides.

Influence of Weather Factors on Seasonal Population Dynamics of <i>Coelaenomenodera elaeidis</i>(Coleoptera: Chrysomelidae) and Its Natural Enemies in NIFOR, Nigeria

The leaf miner (Coelaenomenodera elaeidis) is the major pest of the oil palm. Seasonality of C. elaeidis, its natural enemies and their relationship with temperature, rainfall and relative humidity were observed between January 2009 and December 2010 at the main station of the Nigerian Institute for Oil Palm Research. Leaf miner population estimates were obtained from NIFOR entomology division from 1976-1980. This study analyses temporal patterns in leaf miner abundance, and elucidates general patterns and factors influencing leaf miner abundance. Multiple linear regressions were used to analyse the relationship between abundance of leaf miner, its parasitoids and predators and the following climatic variables: maximum and minimum temperature (°C), rainfall (mm) and relative humidity (%). Climate variables from the month of pest collection (control variable) or from the month before collection (delayed variable) were used. The abundance of leaf miner and predatory ants peaked in the dry season, while parasitoids were most abundant in the rainy season. Significant correlations (P ≤ 0.05) were found between leaf miner, its natural enemies and both control and delayed weather variables. For all years, maximum temperature was the most dominant for all the leaf miner stages. This indicates that the weather variables at both the month of collection and with a delayed month in relation to collection are critical for pest-weather evaluation and important for leaf miner control. Temperature, rainfall and relative humidity had an effect on the population of C. elaeidis, and this effect is manifested primarily in seasonal fluctuations in oil palm agroecosystems. Weather influenced the seasonal population dynamics of C. elaeidis, facilitating early season build-up on the oil palm host crop. Dry season months with resultant higher temperatures recorded higher population of C. elaeidis.

Intercropping Empower Reduces Insect Pests and Increases Biodiversity in Agro-Ecosystem

Currently insect pest management solely depends on chemical pesticide that continuously affects on environment, biodiversity, animal as well as human health. Outbreak of secondary insect pest is also the cost of pesticide use in field leading crop more vulnerable to more pests. These negative impacts of pesticides have provoked growing interest in the adoption of multi-function agricultural biodiversity that promote pest management, creating interesting challenge for traditional approaches to regulatory compliance. To address multi-function agricultural practice, we tested several intercropping systems with mustard and their effect on pest management. Our results revealed that intercropping systems mustard with onion, garlic, radhuni and coriander significantly reduced pest population over sole crop. However, intercropping mustard with wheat and gram increased pest population in mustard field. This result indicated that all crops are not suitable for intercropping system. Among the tested intercropping systems, mustard with onion and coriander significantly reduced branch and flower infestation and increased pod formation per plant. These four intercropping systems did not significantly affect on honeybee pollinator which are crucial for mustard crop yield. A significant linear relationship was also found between honeybee population and pod formation. Our results indicate that suitable intercropping system can be a potential multi-functional agricultural practice for pest management in mustard crop.

Determination of Organochlorine and Synthetic Pyrethroid Pesticide Residues in Water Samples Collected from Different Locations of Bangladesh

The present study was aimed to validate an analytical method for the quantification of 19 organochlorine and 2 synthetic pyrethroid pesticide residues in water samples using modified quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction and Gas Chromatography coupled with Electron Capture Detector (ECD). The selected pesticide residues were determined by in-house validated method. The analytical method was validated by evaluating the accuracy, precision, linearity, limit of detection (LOD) and limit of quantification (LOQ). The average recoveries of the selected pesticides ranged from 78% to 117% with RSDr ≤ 12% in two fortification levels of 0.02 and 0.1 mg/L. The linearity was ≥0.995 for all of the selected pesticides. The LOD ranged from 0.003 to 0.006 mg/L and the LOQ was 0.02 mg/L for all the selected analytes. This method was applied satisfactorily for the residue analysis of 108 water samples collected from nine districts of Bangladesh. Among the analyzed samples, only 4 had cypermethrin residues (0.026 mg/L, 0.034 mg/L, 0.045 mg/L and 0.05 mg/L). The level of detected cypermethrin residues were above the WHO recommended guide line values of water quality.

Incidence and management of white grub, Schizonycha ruficollis on seedlings of teak （Tectona grandis Linn, f,）

In investigation was conducted annually from 2002 to 2005 between the second week of May and the end of September on the incidence of scarab beetle, Schizonycha ruficollis （Fabricius） in a teak （Tectona grandis L.f.） nursery at Ramdongari, Nagpur, India. The immature stages, that is white grubs of the scarab beetle damaged 14%-52% of teak seedlings in the nursery beds, whereas the adult of the species, that is scarab beetles, were recorded on three new host trees （ Ziziphus xylopyra, Acacia catechu and A. leucophloea） in addition to the reported hosts such as ziziphus （Z. jujuba and Z. mauritiana）. Beetles of the S. ruficollis started emerging from the nursery beds just after the pre-monsoon showers and continued for 10-18 days. While beetle of S. ruficollis defoliated tree hosts available in the surroundings, the immature stages of the beetle caused major damage by feeding on root systerfls of teak seedlings with symptoms of wilting and mortality in forest nursery beds. The result of chemical and biological treatments for the management of grubs of S. ruficollis in nursery beds indicated phorate 10% granular at the rate of 20 g/m^2 and chlorpyriphos 20% emulsifiable concentrate at the rate of 5.0 mL/m^2 to be effective. Grubs of S. ruficollis have not been recorded previously as a major pest of teak （T. grandis）. This is also the first report on occurrence of S. ruficollis adults on tree hosts such as Z. xylopyra, A. catechu and A. leucophloea. White grubs being pests of economic importance and the toughest insects to manage, information given in this paper on incidence, pest status and management of Schizonycha ruficollis is of importance to researchers and forest nursery managers.

Role of Ocimum sanctum leaf extract on dietary supplementation in the transgenic Drosophila model of Parkinson's disease

AIM: To evaluate the effect of Ocimum sanctum leaf extract on the dietary supplementation in the transgenic Drosophila model of Parkinson's disease. METHOD: The effect of Ocimum sanctum leaf extract was studied on the transgenic Drosophila model of flies expressing normal human alpha synuclein(h-αs) in the neurons. O. sanctum extract at final concentrations of 0.042 8 × 10-4, 0.87 × 10-4, and 1.85 × 10-4 g·mL-1 of diet were established and the flies were allowed to feed for 21 days. The climbing assay and lipid peroxidation were taken as parameters for the study. RESULTS: The supplementation of O. sanctum extract showed a dose-dependent significant delay in the loss of climbing ability and reduction in oxidative stress in the brain of PD model flies. CONCLUSION: The results of the present study showed that the O. sanctum extract is potent in reducing the PD symptoms in transgenic Drosophila model.