In evaluating the effect of plant extract of bitter melon ( Citrullus colocynthis ) on the Ch. trachypterus grasshopper revealed that the extract has insecticidal effect and the mortality rate rises with increasing concentrations and with the passage of time. Other studies also show the sensitivity difference of the insect and the plant lethal power in different concentrations (Torkey et al., 2009; Abdul Rahman and Venkatesan, 2008). Mullai and Jebanesan in 2007 examined the effect of bitter melon extract against the mosquito of Culex quinquefasciatus (Dip: Culicidae). The results suggested that bitter melon extract has toxic and lethal effects on the insect studied and mortality enhanced with increasing concentration. The results of Rawi et al., 2011 indicate that the methylene chloride extract of bitter melon has insecticidal effect on larvae of Spodoptera littoralis . According to the results of this research and other studies, it can be concluded that the Chrotogonus trachypterus grasshopper has reasonable sensitivity to bitter melon extract. This plant extract can be introduced as an alternative to conventional synthetic pesticides against the mentioned pests. It should be noted that further scientific studies in biochemistry and technical levels are required to use of the plant compounds and formulating them.
Studies have shown that the essential oil of Cinnamomum zeylanicum is mainly composed of cinnamaldehyde . Some American companies have recently taken advantage of this situation and have been able to bring essential oil based on cinnamon pesticides to market, with cinnamaldehyde as the active ingredient . However, it would be difficult to think that the insecticidal activity of this oil is limited only to some of its major constituents; it could also be due to certain minor constituents or to a synergistic effect of several components .
Crataeva religiosa is of the family of Capparidaceae. Several studies showed that spe- cies of the family of Capparidaceae showed the insecticidal effect of the organic extracts on the devastating insects of stocks of harvest. Among this work, one can et al . quote those of Gueye   which showed the insecticidal activity of Boscia senegalensis on Caryedon serratus (groundnut beetle) . It is interesting to mention work of Seck et al .  which obtained in direct application of fruits and sheets of B. senegalensis to amounts from 2% to 4% (P/P) 80 to 100% of mortality of the adults of C. maculatus and significantly reduces at the same time the emergence and the damage of F1. Many work also showed that the organic extracts of plants give insecticidal effects on the de- vastating insects of stored food products. The toxicity of the extracts with organic sol- vents of Afrostyrax lepidophilus , Trichilia gilgiana , Drypetes gossweileri and Zanha golungensis with regard to Sitophilus zeamaïs , Tribolium castaneum and Rhyzopertha dominica is shown by work of Toumnou .
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A glycoside Cucurbitacin E separated from Citrullus colocynthis was examined for insecticidal activity against Aphis craccivora with extraction with extraction acquired from various solvents like methylene chloride, chloroform 50, ethanol and n-hexane. The ethanolic extract demonstrated the most noteworthy insecticidal effect (LC 11003 ppm) against A. craccivora. After further extraction of the deposit staying after vanishing of ethanolic extract with nine solvents, the butanol portion demonstrated the most noteworthy insecticidal effect (LC3123.10 ppm). This insecticidal strength of C. colocynthis extract is because of the presence of active ingredients like glycosides, saponin, and alkaloids. Overall analysis, conclude that this compound showed an insecticidal effect against Aphis craccivora .
Background: Long-lasting insecticidal mosquito nets (LLINs) are highly effective for malaria prevention. However, it is also clear that durability monitoring is essential to predict when, post-distribution, a net population, no longer meets minimum WHO standards and needs to be replaced. Following a national distribution campaign in 2013, we tracked two durability indicators, physical integrity and bio-efficacy at six and 12 months post-distribution. While the loss of net integrity during this period was in line with expectations for a one-year net life, bio-efficacy results suggested that nets were losing insecticidal effect faster than expected. The rate of bio-efficacy loss varied significantly between different net brands.
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Five empty tins were washed and dried using a neat piece of cloth material. The tins were perforated at the base center using a sharp knife and were all tightly covered with their lids. Three pairs of adult cockroaches were placed into the different containers through the perforated base and the ground plant materials were added to each of the different containers having the cockroach except the control. The perforated bases were then blocked with cotton lint to prevent the cockroaches from escaping and to allow adequate ventilation into the cans. The cans were allowed to stand undisturbed for 24 hours, after which the lids were removed for observation. The method used for the adult cockroach above was also used on Diphtheria specie (wall fly) and brown field hoppers one after the other. The insecticidal effect of the plant material was tested on mosquito larva as well. Water was collected in five big bowls and kept in a grass lawn for 9 days. At the end of the 9 th day, mosquito larva were seen thriving on the stagnant water in large numbers in different bowls. The different plant materials were crushed and poured into the mosquito larva habitat and allowed to stand for 24 hours, the control was not treated with any plant samples. After 24 hours, almost all the mosquito larva breeding in these bowls died and there was little or no movement in the water contained in the bowls. However mosquito continued to breed in the control.
Previous studies of permethrin sandfly anti-feeding ef- ficacy, either as the single active ingredient or in various combination spot-on formulations [7-9], have shown a similar pattern of extended blood feeding prevention over two to four weeks after treatment, together with relatively shorter and lower knock-down effect. Molina et al . , particularly, demonstrated that 65% permeth- rin applied to dogs as a spot-on had satisfactory anti- feeding effect (> 65%) lasting 3 weeks and immediate insecticidal effects (> 40%) lasting 2 weeks after initial application, which is consistent with the present results . Similarly, highly comparable results were reported by Miró et al .  with a combination of imidacloprid 10% (w/v)/permethrin 50% (w/v) spot-on, with an imme- diate insecticidal effect (assessed after 1 hour of sand fly exposure) within the first week of application (> 40%), and an anti-feeding effect of over 90% during the first 3 weeks of the study . Recent results obtained with the addition of 4.95% dinotefuran in the combination 36.08% permethrin-0.44% pyriproxyfen have demon- strated both persistent knock-down effect and insecticidal activity 7 days (> 95%), 2 weeks (> 70%) and up to 4 weeks after treatment (about 40%) .
Regarding the two LLINs, unwashed Permanet 3.0 induced significantly higher BFI and mortality than Per- manet 2.0 in Vallée du Kou and Malanville. In the local- ity of Pitoa, the BFI was however higher with Permanet 2.0 than Permanet 3.0 but the mortality was still higher with Permanet 3.0. After 20 washes, the PermaNet® 3.0 also induced higher insecticidal effect than PermaNet® 2.0 in the pyrethroid resistance areas of Pitoa and Vallée du Kou, but performed equally in the area of Malanville. One should note that in areas with high resistance levels (Vallée du Kou) 50% of resistant mosquitoes sur- vived after exposure to PermaNet® 3.0 relative to 75% survival after exposure to PermaNet® 2.0. It remains to be seen if the gain of efficacy of PermaNet® 3.0 over Per- maNet® 2.0 is enough to control highly pyrethroid-resis- tant malaria vector populations. Here, it is difficult to conclude on the benefit of using PBO on the roof because the deltamethrin content on PermaNet® 3.0 was approximately twice higher than that of PermaNet® 2.0. So the better efficacy on resistant mosquitoes could be impeded either to the higher deltamethrin concentration or to the PBO itself or both. Other field studies did not show an increase of efficacy on resistant Culex and pyrethroid susceptible An. gambiae s.s.  as well as deltamethrin-resistant Anopheles epiroticus .
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The Cruiser with its insecticidal effect also pro- vides control against persistent virosis transmitted by sucking insects. According to our experiences, the effective duration even of the best dressing preparations remains about 4–5 weeks. In the case of next pressure of pests shows necessary applica- tion of an insecticide. The same effective duration of imidacloprid seed treatment against Cabbage Aphid (Brevicoryne brassicae) detected by Schroeder et al. (2001). The effectiveness of seed treatment considerably decreased six weeks after sowing.
Several studies showed that species of the family of Capparidaceae showed the insecticidal effect of the or- ganic extracts on the devastating insects of stock of harvest. Among this work, it can quote those of Gueye et al.  which showed the insecticidal activity of Boscia senegalensis on Caryedon serratus (groundnut beetle). Many work also showed that the organic extracts of plant give insecticidal effects on the devastating in sects of stored food products. The toxicity of the extracts with organic solvents of Afrostyrax lepidophilus, Trichilia gil- giana, Drypetes gossweileri and Zanhagolungensis with regard to Sitophilus zeamaïs, Tribolium castaneum and Rhyzopertha dominica is shown by work of Aba Toumnou 22 .
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From March to September 2013, children 6–59 months who presented to the under-five outpatient clinic at Machinga District Hospital were recruited into a case– control study to assess the personal protective effect of LLINs on malaria morbidity . Inclusion criteria were residence within 15 km of the hospital and axillary tem- perature ≥ 37.5 °C (as measured by the survey team) or history of fever within the past 48 h (per caregiver report). After written informed consent was obtained from the caregiver, participants were enrolled in an overall study of the association between bed net use and malaria risk. Surveyors administered a questionnaire that included information on illness history, socioeconomic status, malaria risk factors, and LLIN use. Thick and thin blood films as well as an RDT for malaria (Paracheck Pf ® device, Orchid Biomedical Systems, India) were
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Bacillus thuringiensis, commonly known as Bt, is a Gram positive, rod-shaped, ubiquitous soil-dwelling and endospore forming bacterium (Hofte and Whiteley, 1989; Glare and O’Collaghan, 1998; Ibrahim et al., 2010). Colonies of B. thuringiensis are described as circular to irregular with entire or undulate edges, and have matt to granular surface textures (Logan and De Vos, 2011). B. thuringiensis belongs to the Bacillus cereus group but it is mainly characterized by its capability of producing crystalline protein inclusions that contain one or more insecticidal δ-endotoxins, during the sporulation phase of its life cycle (Glare and O’Collaghan, 1998; Helgason et al.,1998; Stotzky, 2004; Ibrahim et al., 2010).
resulting in a destruction of cell membranes (Kuhn-Nentwig et al., 2002). Histamine, a neurotransmitter in insect nerve systems (Nässel, 1999) and present in the spider venom, caused a significant mortality increase of 20% when co-injected with CSTX-1, but was less effective in combination with CSTX-9 or CSTX-13 in Drosophila flies (Wullschleger et al., 2004). Taurine, a neuromodulator in insects (Bicker, 1991) and also present in the spider venom had no paralytic effect when co- injected with CSTX-1, CSTX-9 or CSTX-13. By contrast, we were previously able to show in a blow fly bioassay that the neurotoxicity of CSTX-1 was enhanced by both taurine and histamine when injected in its physiological venom concentrations (Kuhn-Nentwig et al., 1998). This could indicate that synergistic interactions are highly species and neurotoxin specific, despite the close relationship between both fly families.
larvae of Culiseta longiareolata were studied. The toxicity observed was in the order: gyrophoric acid > (+)-usnic acid > atranorin > 3-hydroxyphysodic acid. In a study, compounds viz. 2-hydroxy-4-methoxy-6-propyl-methyl benzoate and the (+)-usnic acid isolated from the methanol extract of Ramalina usnea by column chromatography were capable of exhibiting larvicidal activity against III instar larvae of A. aegypti with LC50 value of 4.85 and 4.48 µg/ml, respectively (Moreira et al., 2016). Study carried out by Martins et al. (2018) showed dose- dependent insecticidal activity of usnic, fumarprotocetraric, and barbatic acids isolated from the lichens Cladonia substellata, C. verticillaris, and Cladia aggregata, respectively, against the termite Nasutitermes corniger. It is shown in a recent study that fluorine-containing usnic acid and the fungus Beauveria bassiana were shown to exhibit synergistic insecticidal activity against Colorado potato beetle larvae (Kryukov et al., 2018). More information on the insecticidal activity of lichen metabolites is presented in Table 2. Structure of some lichen metabolites (that are reported to possess insecticidal properties) is shown in Table 3.
Sarcanthus pauciflorus is a pendulous epiphytic orchid belonging to the family Orchidaceae. The present study was conducted to determine antimicrobial, antioxidant, anthelmintic and insecticidal efficacy of methanol extract of S. pauciflorus. Antimicrobial activity of methanol extract was determined against four bacteria and two fungi by Agar well diffusion method. Antioxidant activity was performed by DPPH free radical scavenging and Ferric reducing assay. Anthelmintic activity was studied on the basis of time taken for paralysis and death of adult Indian earthworms by the extract. Insecticidal activity, in terms of larvicidal effect, was evaluated using II instar larvae of Aedes aegypti. Total phenolic content of extract was estimated by Folin-Ciocalteau reagent assay. Phytoconstituents viz., tannins, saponins and glycosides were detected in methanol extract. Content of total phenolics was found to be 258.65 mg GAE/g of extract. All test bacteria and fungi were susceptible to extract of orchid. Bacillus subtilis and Cryptococcus neoformans were susceptible to high extent among bacteria and fungi respectively. Gram positive bacteria have shown greater susceptibility than Gram negative bacteria to extract. The extract exhibited marked dose dependent scavenging of DPPH free radicals. An increase in absorbance at 700nm revealed reducing power of the extract. The extract caused paralysis and death of adult Indian earthworms in a dose dependent manner. The lethal effect of extract on II instar larvae of Aedes aegypti was found to be dose dependent. The results of the present study shows that the methanol extract of S. pauciflorus is found to possess antimicrobial, antioxidant, anthelmintic and insecticidal activities which might be attributed to the presence of secondary metabolites. Further experimentations concerned with isolation of the bioactive components present in the orchid and determination of their biological activities are under progress.
Crossandra infundibuliformis is a popular tropical flower known as “Firecracker”, It is a species of flowering plant in the family Acanthaceae, native to southern India and Sri Lanka. It is traditionally used for the treatment against various ailments in tropical and subtropical parts of India without any scientific knowledge. In the present study the anticancer and insecticidal activity of the ethanolic extract of the leaves of Crossandra infundibuliformis were investigated. Anticancer activity evaluated against human breast cancer cell line (MCF-7) by MTT assay method and the insecticidal activity was evaluated against Wheat weevil (Sitophilus oryzae). Both the activities were dose dependent. IC 50 value of anticancer activity against MCF-7 cell line was found to be 404.66 µg/ml. Maximum
The binary combinations of the essential oils of C. ambrosioides and Cu. sempervirens tested on maize were very efficient insecticides against the maize weevils. These potentials to control the proliferation of S. zeamais in stored maize was also dose dependent and increased with period of exposure. Therefore both EOs can be recommended for their insecticidal, progeny control effects, high repellence and ability to prevent grain from damage caused by maize weevils and can be easily used in an integrated pest management practice.
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E. tirucalli is widely used in traditional medicinal system. Most recently E. tirucalli is reported for various medicinal properties (Figure1). Stem bark and leaves are reported to possess antibacterial activity. 2 Aerial parts of E. tirucalli are reported to possess antioxidant activity. 4 Organic solvent exhausted material of E. tirucalli is reported to have antiarthritic activity. 5 Latex is reported to possess proteolytic activity 6 , anticancer activity 7 , molluscidal activity 8 and larvicidal activity. 9 Stem of E. tirucalli is reported to possess insecticidal activity. 10 The present review is focused on overall outline of the medicinal properties and biomolecules of E. tirucalli and its future prospects for the further scientific investigation for the development of effective therapeutic compounds.
Long-lasting insecticidal nets (LLINs) are a key vec- tor control intervention used to reduce malaria trans- mission and recommended to be used by all popula- tions at risk of malaria (World Health Organization 2008). LLINs provide a combined physical and chem- ical barrier protecting those who sleep under them. In addition, sustained wide-spread LLIN use can provide a community-wide and mass effect where vector lon- gevity, density, and humanÐvector contact is reduced (Hawley et al. 2003, Lengeler 2004, Killeen et al. 2007). LLINs were speciÞcally developed to overcome the cost and logistical issues of having to retreat bednets with insecticide, as with LLIN the insecticide is im- pregnated into the Þlaments of the fabric during man- ufacture, producing a slow release effect over 3Ð5 yr
Pesticides may be applied to protect new flushes of growth when the leaves are most vulnerable to CLM damage. However, the best foliar insec- ticides keep leaves free of leaf miner infestations for only two weeks (Michaud & Grant 2003). Recently, Mafi and Ohbayashi (2006) found that the percentage corrected mortality of eggs of the citrus leafminer exposed to insecticides (dipping method bioassay) ranged from 3% to 44%, while all tested insecticides gave almost over 90% mortality to the first instar larvae of the citrus leafminer. It is important to select chemicals that are less toxic to the natural enemies to take advantage of both the activity of natural enemies and the control effect of insecticides for suppressing the infestation by CLM.