IN VITRO PROPAGATION OF ANTHURIUM (Antlwrium andraeanum L)

Callus induction and shoot regeneration were studied using leaf and petiol cxplants of invitro cultures of white Anthuriurn and leaf ex plants of green house grown nine Anthuriumcultivars (Cassino, Tropical, SHP, Samangi, Maringue Lady Jane, White, Magic Red andPierot).Leaves from in vitro cultures of Anthuriurn were cultured in MS medium supplementedwith 1.0mgIL BA 0,0.2 & 0.5 mg/L IAA and incubated in dark at 25° C temperature. Theeffect of IAA was significant for callus induction and shoot regeneration. The highestcallus quantity (6.75) showed in 0.2mgIL IAA while only 2 shoots regenerated from Omg/lIAA. PeLioles from in vitro cultures of Anthurium were also cultured MS mediumsupplemented with combination of 2 levels of BA (lor 2mgIL) and 3 IAA levels (0,0.2 &0.5mglL).Cultures were incubated in dark at 25° C temperature. Significant differenceswere found between the two BA levels and 3 IAA levels for callus production and shootregeneration. The highest callus quantity (5.6) was given in ImgIL BA with 0.2mgIL IAAthan other combinations. Higher shoot regeneration was achieved in 0.2 and 0.5 mglL IAAwith I or 2 mgIL BA (2.7-2.9 shoots per explant).Leaf pieces (1cm* ICIII) from green house grown 9 cultivars were sterilized and cultured inMS medium supplemented with ImgIL BA and 0,0.2 or 0.5 mg/L IAA and incubated darkat 25° C temperature. Significantly higher callus quantity was observed in 0.2 mgfL IAAwhile the lowest callus quantity was from OmgIL IAA level. A significant difference wasobserved among 9 cultivars from callus production. The highest callus quantity (4.74) wasobserved from the cultivars "Lady Jane" while the lowest callus quantity (1 from cultivar)"Pierot". Shoot regeneration was observed in some cuItivars after 4-5 months. For example,cultivar "Meringue" produced 3 shoots per explant in O.5mg/L IAA level and cultivar"Cassino" produced I shoot per explant in 0.2mglL IAA level. Shoot regeneration was notachieved in other cultivars.

Epidemic of Plasmodium falciparum Malaria Involving Substandard Antimalarial Drugs, Pakistan, 2003

To prevent future epidemics, enhanced quality assurance is essential

Epochal changes in the association between malaria epidemics and El Niño in Sri Lanka

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

The dominant Anopheles vectors of human malaria in the Asia-Pacific region: occurrence data, distribution maps and bionomic précis

<p>Abstract</p> <p>Background</p> <p>The final article in a series of three publications examining the global distribution of 41 dominant vector species (DVS) of malaria is presented here. The first publication examined the DVS from the Americas, with the second covering those species present in Africa, Europe and the Middle East. Here we discuss the 19 DVS of the Asian-Pacific region. This region experiences a high diversity of vector species, many occurring sympatrically, which, combined with the occurrence of a high number of species complexes and suspected species complexes, and behavioural plasticity of many of these major vectors, adds a level of entomological complexity not comparable elsewhere globally. To try and untangle the intricacy of the vectors of this region and to increase the effectiveness of vector control interventions, an understanding of the contemporary distribution of each species, combined with a synthesis of the current knowledge of their behaviour and ecology is needed.</p> <p>Results</p> <p>Expert opinion (EO) range maps, created with the most up-to-date expert knowledge of each DVS distribution, were combined with a contemporary database of occurrence data and a suite of open access, environmental and climatic variables. Using the Boosted Regression Tree (BRT) modelling method, distribution maps of each DVS were produced. The occurrence data were abstracted from the formal, published literature, plus other relevant sources, resulting in the collation of DVS occurrence at 10116 locations across 31 countries, of which 8853 were successfully geo-referenced and 7430 were resolved to spatial areas that could be included in the BRT model. A detailed summary of the information on the bionomics of each species and species complex is also presented.</p> <p>Conclusions</p> <p>This article concludes a project aimed to establish the contemporary global distribution of the DVS of malaria. The three articles produced are intended as a detailed reference for scientists continuing research into the aspects of taxonomy, biology and ecology relevant to species-specific vector control. This research is particularly relevant to help unravel the complicated taxonomic status, ecology and epidemiology of the vectors of the Asia-Pacific region. All the occurrence data, predictive maps and EO-shape files generated during the production of these publications will be made available in the public domain. We hope that this will encourage data sharing to improve future iterations of the distribution maps.</p

Laboratory and field comparisons of pyriproxyfen, polystyrene beads and other larvicidal methods against malaria vectors in Sri Lanka.

Hand-dug gem pits are important breeding sites for larvae of malaria vectors in Sri Lanka. Therefore, studies were carried out to help to select an effective, economic and convenient method that could be used to control malaria vector mosquito breeding in gem pits in a mining area. The effectiveness of four types of floating layers of polystyrene was compared in the laboratory and it was found that 2 mm expanded beads were the most effective for suffocating Anopheles larvae and pupae. The insect growth regulator, pyriproxyfen at dosages of 0.01 and 0.1 mg/l were tested in the laboratory and complete inhibition of emergence was found at both concentrations. A small-scale field trial was carried out for over a year to assess the efficacy of two concentrations of pyriproxyfen, 2 mm diameter expanded polystyrene beads, temephos, used engine oil and filling pits with soil. Pyriproxyfen only required re-application twice a year, whereas temephos or oil require 12 applications per year. Due to re-excavation by gem miners, polystyrene beads and filling of pits were not as permanent solutions as was expected. Calculations based on all available data showed that two annual treatments with pyriproxyfen at 0.01 mg/l would be the most cost-effective method with oil only slightly more expensive. However, the reduced required frequency for visiting every pit made the pyriproxyfen method the one of choice. The same low concentration of pyriproxyfen also effectively inhibited emergence of adults from river-bed pools

Control of vectors and incidence of malaria in an irrigated settlement scheme in Sri Lanka by using the insect growth regulator pyriproxyfen.

An evaluation of pyriproxyfen as a larval control agent with the aim of reducing malaria vector populations and incidence of malaria was conducted in 12 villages in an irrigated settlement scheme in the dry zone of central Sri Lanka. In these villages, there are many pools in the beds of rivers, streams, and irrigation ditches during the dry season of the year. These are the major breeding places of the malaria vectors Anopheles culicifacies and An. subpictus. Collections of adult mosquitoes were carried out by using standard methods and parasitological data were collected by daily malaria clinics set up for the project and through the 2 government hospitals. All villages in the study area were under residual house spraying with lambdacyhalothrin water-dispersible powder. Using the 1st year's baseline data collection, the villages were stratified into 6 villages with high malaria incidence and 6 villages with low incidence. Within each group, 3 villages were randomly assigned for larval control by treating all the pools in the beds of rivers, streams, and irrigation ditches and agricultural wells with a granular formulation of the insect growth regulator pyriproxyfen at the rate of 0.01 mg active ingredient/liter. The field bioassays indicated that a single treatment of pyriproxyfen effectively inhibited the emergence of adult mosquitoes in the riverbed pools for a period of 190 days. The treatment caused significant reduction of the adult populations of An. culicifacies (78%) and An. subpictus (72%). Similarly, incidence of malaria was reduced in the treatment villages by about 70% (95% confidence interval 58-78%) compared with the controls. The conclusion is made that pyriproxyfen can be a very effective means of malaria control if all possible vector breeding places in the area can be located

Control of malaria vectors with the insect growth regulator pyriproxyfen in a gem-mining area in Sri Lanka.

The study was conducted in eight adjacent villages in central Sri Lanka where there are many shallow pits dug by gem miners that fill with water. These become breeding places of the main malarial vector Anopheles culicifacies, and of the second most important vector Anopheles subpictus, but not of Anopheles varuna, the third most important vector. With the help of local volunteers, data on the adult populations of these three species was collected by various standard methods, and data on the incidence of malaria cases was collected by two clinics set up for the project and through the existing hospitals. Prevalence of malaria infection in symptom-less people was investigated by mass blood surveys. On the basis of a year's pre-intervention data the villages were stratified into four with high levels of malaria transmission and four with lower transmission. Within each stratum two villages were randomly assigned for mosquito control by treating all the gem pits, as well as river bed pools, with a granular formulation of the insect growth regulator pyriproxyfen at a target dose of 0.01 mg a.i./litre. The intervention caused significant reductions in the adult populations of An. culicifacies and An. subpictus. Similarly, incidence of malaria was reduced in the intervention villages to about 24% (95% c.l. 20-29%) of that in the controls. Prevalence of parasitaemia also declined significantly. It is concluded that in this situation where, with active community participation, the breeding sites of the main vectors could be located; vector control by a highly active and persistent insect growth regulator can be a very effective means of malaria control

Evaluation of alternatives to expanded polystyrene beads for mosquito control

Expanded polystyrene (EPS) beads have been shown to be an effective tool for controlling immature stages of mosquitoes, as well as preventing oviposition by adults. Polystyrene does not biodegrade quickly, resulting in some concerns about its effect on the environment. A potential solution is the use of biodegradable materials that cover the surface of mosquito breeding sites in the same way as EPS beads. Two candidates are polylactic acid (PLA) beads and corn starch shreds. Larval mortality and adult emergence of Culex quinquefasciatus Say (Diptera: Culicidae) were monitored in bowls with each of four treatments: EPS beads, PLA beads, corn starch shreds and a control. The PLA beads were as effective as EPS beads at preventing mosquito emergence, whereas the shredded corn starch treatment resulted in significantly higher rates of emergence to the control. Similarly, EPS and PLA beads resulted in 100% mortality after 10days, while there was low mortality of larvae in the corn starch (9%) and control treatments (20%). PLA beads provided similar levels of mortality and reduction in adult emergence as EPS beads. However, the production requirements of PLA beads may limit its use in field conditions

Vectors and malaria transmission in a gem mining area in Sri Lanka.

Anopheline vectors of malaria were studied in the Kaluganga gem mining area in the dry zone of central Sri Lanka. Adult mosquitoes were collected using cattle-baited huts and nets, pyrethrum spray sheets, window exit traps and light traps and partial and full-night human landing collections over a period of 17 mo. The collections produced a total of 13,591 anophelines belonging to 14 species. Using ELISA for circumsporozoite proteins of Plasmodium vivax and P. falciparum, Anopheles culicifacies, An. subpictus and An. varuna were incriminated as malaria vectors. For these species, estimated entomological inoculation rates were 5.9, 5.7, and 6.7 infective bites per person per year, respectively. An. culicifacies and An. subpictus show endophagic behavior, while An. varuna were exophagic. Mosquito larval surveys indicated that the gem pits, when filled with water, contributed 60% of the larvae of the three vector species. Parasitological data were collected by two mobile malaria clinics and by hospitals. The incidence rates of fever per 1,000 person-years with P. vivax and P. falciparum were 122.8 and 26.1 respectively, with a significantly higher rate in males over 15 years of age than in females of that age. Changes in the environment due to gem mining may have caused the emergence of An. subpictus and An. varuna as significant malaria vectors. The conventional view of An. culicifacies being the main vector of malaria in Sri Lanka needs to be reconsidered when planning the vector control programs in this study area. Due to migration of malaria patients, there is a likelihood the disease could be spread to other parts of the island. Therefore, action should be taken to eliminate these pits as breeding sites