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The current study was designed to evaluate the efficacy of four plant extracts, i.e., cassia (Acacia farnesiana Willd), arbor-vitae (Platychladus [Thuja] orientalis Endl, mahogany [Swietenia mahogany (Linn.) Jaq], and pancratier-lily (Pancratium maritimum L.), as protectants against the cowpea weevil (Callosobruchus maculatus). Results obtained showed that at a concentration of 5 g crude extract/kg seed, there was a significant reduction in the percentage of egg hatching. The cassia and arbor-vitae extracts from leaves or seeds appear to reduce egg hatching (0.5 and 30.0%) and (4.0 and 26.0%), respectively. Complete inhibition in adult emergence was found by the ethanolic extract of cassia seeds. The extracts obtained from cassia mahogany leaves also showed strong ovicidal activity. The egg hatching percentage significantly decreased during the 8-month storage of cowpea treated with ethanol extract of cassia and arbor-vitae seeds with values of (52-53%) and (51-58%), respectively. The results also demonstrated that surface treatment of cowpea seeds with most selected extracts did not affect the germinative potential of cowpea seeds compared with the control extract the ethanol extract of cassia and arbor-vitae leaves which had 80 and 75% germination, respectively compared to the control 95%. Water absorption did not also differ significantly between all treatment and control samples. In conclusion, current study investigated that tested plant extracts can be used as cowpea seeds protectants and can be used in IPM program. [ABSTRACT FROM AUTHOR]

In this study, eight invasive plant species were processed into botanical pesticides, and their bioefficacy was tested against the two-spotted spider mite, Tetranychus urticae. The evaluated botanical pesticides showed high toxicity against adult females of T. urticae, where the mortality ranged from 39.5–99.5% in the treatment groups, while the mortality was 0.5% in the control. Moreover, the oviposition deterrence activity of the botanical pesticides was reflected by the lower number of eggs laid in the treatment groups (9.1–255.5 eggs) compared to the control (504.8 eggs). The ovicidal activity bioassay revealed that the hatchability of eggs following the application of botanical pesticides was reduced to 63.5–95.5%, while the hatchability was 98.8% in the control. However, the ethanolic leaf extract of Mimosa pudica seemed to be the most efficacious botanical pesticide in all parameters observed since it showed high efficacy even when applied at a concentration of 7.5 g/L instead of 10 g/L. Through gas chromatography-mass spectrometry (GC/MS) analysis, 15 phytoconstituents that might be responsible for the anti-mite features were identified. The botanical pesticides used in this study have the potential to be used as environmentally friendly measures to manage T. urticae particularly in organic farming. [ABSTRACT FROM AUTHOR]

Background: Trematode infections are of great importance as they affect the health of many species of mammals as cattle, sheep and goat. Fasciola hepatica represents the main trematode zoonosis and risks to human and cattle and paramphistomosis is one emerging parasitic diseases of ruminants widely distributed in the world. The economic expenses are incurred by the use of ineffective anthelmintics for trematode control. Besides to faecal egg count reduction test (FECRT) to determine the anthelmintic efficacy, can be used in vitro assays, by this the aim of the study was to determine the lethal doses (LD) with hatching egg test (EHT) of the main commercial anthelmintics used for the control of trematodes in cattle. Materials, Methods & Results: Liver and rumen were examined from cattle slaughtered in Tabasco, Chiapas and Campeche states from Mexico. F. hepatica eggs were recovered from gallbladder and rumen fluke eggs collected from adult parasites in saline solution. Subsequently, the hatching egg assays were performed placing 100 trematode eggs in distilled water in each one of 96 wells of polystyrene plates. After making the appropriate dilutions, several concentrations of commercial anthelmintics were evaluated, ranging from 0.04 to 80.63 mM for triclabendazole + 0.046 to 96.87 mM febendazole (TC+FBZ), from 0.04 to 91 mM for rafoxanide (RAFOX), from 0.02 to 43.74 mM for closantel (CLOS), from 0.036 to 76.18 mM for clorsulon + 0.002 to 3.31 mM ivermectin (CLORS+ IVM) and from 0.163 to 334.47 mM for nitroxynil (NITROX). A control group (water) was included in each plate. Lethal doses were obtained using the Probit procedure and analysis of the means with a one-way statistical design. Most drugs used against rumen fluke eggs presented a high LD50 and therefore were ineffective to cause egg mortality, such was the case of RAFOX that presented LD50 from 4,580 to 10,790 µg/mL (7 to 17 mM). CLOS presented the lowest LD50 (80 µg/mL or 0.12 mM) on rumen fluke eggs. TC+FBZ was found to be effective drug against the development of F. hepatica eggs in many samples. In the same way NITROX showed a low LD50 (37 to 63 µg/mL or 0.13 to 0.22 mM), but RAFOX presented a highest LD50 (1,450 µg/mL or 2.32 mM). Discussion: The present study focused on screen the ovicidal activity and determining in vitro lethal doses 50 of main commercial anthelmintics used to control F. hepatica and rumen fluke as rapid tests in a tropical region from Mexico. The FECRT is the main method to detect effectiveness of anthelmintic and other method is the coproantigen reduction test (CRT) by ELISA. Both tests require many infected animals depending the number of treatments and by this the egg hatch assay (EHA) represent a complementary diagnosis of effectiveness of anthelmintic products to compare between regions and even between farms, because few animals are required from the farm to collect trematode eggs, and it is possible to know the effectiveness against various anthelmintics at the same time. Efficacy studies on trematodes using egg hatching tests are scarce, although they have the advantage that they can be applied to both F. hepatica and rumen fluke. TC+FBZ was one of the most effective products in inhibiting the development of F. hepatica eggs. However, RAFOX showed low effectiveness against trematode eggs, with very high lethal doses. These results agree with a study that show low efficacy against the development of Paramphistomum cervi eggs and with the FECRT test reductions of 75% and 80.58% were obtained, in times from 7 to 84 days after treatment with RAFOX. NITROX and CLORS were drugs that had good efficacy on the development of F. hepatica eggs. A differential response between liver and rumen fluke was observed. The anthelmintics used against rumen fluke eggs show low ovicidal activity and in Fasciola hepatica TC+FBZ show the best activity. [ABSTRACT FROM AUTHOR]

Abstract Background The limited ovicidal activity of currently available acaricides is a significant obstacle to efficacious scabies treatment. Several essential oils or their respective components have proved to be active against the eggs of arthropods, mainly lice and ticks. Information on the activity of these oils and/or components against the eggs of mites remains very limited. The aim of this study was to assess the activity of six terpenes (carvacrol, eugenol, geraniol, citral, terpinen-4-ol and linalool) commonly found in essential oils against the eggs of Sarcoptes scabiei. Methods Sarcoptes eggs were exposed to paraffin oil containing 1, 2.5, or 5% of each terpene tested. After a 12-h exposure period, the eggs were washed and placed in paraffin oil for hatching. Embryonic development following treatment was assessed every day to determine the stage of developmental arrest. Results The median effective concentration to obtain 50% egg mortality (EC50) was 0.5, 0.9, 2.0, 4.8, 5.1 and 9.8% for carvacrol, eugenol, geraniol, citral, terpinen-4-ol and linalool, respectively. The microscopic images of eggs after each treatment indicated that these six terpenes may act by penetrating through the aeropyles on the egg surface. Conclusions In conclusion, carvacrol, eugenol and geraniol possess significant ovicidal activities, which should be considered as promising ovicidal agents for the treatment of scabies. Graphical Abstract

Abstract Background The use of plant-based formulations is an easy and economical method to control insect pests. The objectives of the present study were to evaluate ovicidal and larvicidal potential of ethanolic leaf extracts of four plants, Cyathocline purpurea, Blumea lacera, Neanotis lancifolia, and Neanotis montholonii, and their effects on gut histology of Aedes aegypti (Diptera: Culicidae) larvae. We identified the phytochemicals present in the ethanolic extracts of these plants by LC-MS analysis. The eggs and larvae of A. aegypti were exposed to four concentrations (0.05, 0.1, 0.2, and 0.3 mg/mL) of crude ethanol extracts for different time durations. We observed egg hatching for 48 h, mortality, and gut histology of the 3rd instar larvae after 24, 48, and 72 h of treatments. Results LC-MS analysis revealed the presence of various active compounds such as alkaloids, tannins, saponins, and flavonoids in the ethanol extracts of all these plants. The extracts of all plants showed ovicidal activity. The extracts of C. purpurea showed the highest larvicidal activity (LC50 at 72 h = 0.088 mg/mL) followed by B. lacera (LC50 at 72 h = 0.758 mg/mL) while N. lancifolia and N. montholonii extracts did not show significant larvicidal activity. All plant extracts affected gut morphology in concentration and treatment duration-dependent manner. The plant extracts used in the present study have ovicidal properties and affected the gut histology of A. aegypti larvae. Conclusion These results suggest that C. purpurea has the highest larvicidal activity against A. aegypti larvae and can be further evaluated for application purposes.

The objective of this study was to evaluate the in vitro ovicidal activity, phytochemistry, and toxicity of a saline extract obtained from peel of Punica granatum L fruits. The ovicidal activity was evaluated by the hatching inhibition of eggs recovered from fecal samples of naturally infected goats; the phytochemical analysis was carried out using the fruit peel; and the toxicity was tested on Artemia salina, using saline extract. The results showed that the ovicidal effect of the tested extract was 99% (25 mg mL−1), 99% (12.5 mg mL−1), 98% (6.25 mg mL−1), and 95% (3.12 mg mL−1), higher than that of the control drug, thiabendazole (83%). The phytochemical analysis showed presence of phenols, anthraquinones, and condensed and hydrolysable tannins in the fruit extract. The toxicity test of the extract of P. granatum showed an LC50 of 6.19 mg mL−1, which indicates a safe use for a concentration of 3.12 mg mL−1, since it was the tested concentration that was below the reliable LC50. The saline extract from peels of P. granatum has ovicidal activity, important secondary metabolites, and absence of toxicity at the lowest concentration tested. However, in vivo tests in experimental models are recommended before performing experiments in ruminants. [ABSTRACT FROM AUTHOR]

Haemonchus contortus (HC) is a gastrointestinal nematode of worldwide importance due to the economic losses it causes directly and indirectly in sheep production. Plant extracts rich in secondary metabolites have been proposed as an alternative method of gastrointestinal nematode control in sheep and goats, as they fulfill their biological function and a sustainable environmental accompaniment. The objective of the present experiment was to determine the effect of the hydroalcoholic extract of Leucaena leucocephala leaves (EHLL) on the hatching of Haemonchus contortus in vitro. The extract was obtained by the maceration technique and was subjected to qualitative phytochemical characterization, in which instaurations, phenolic oxydryls, lactones, flavonols, floratanins, coumarins, saponins and aromatic compounds were identified. Concentrations of 100, 90, 80, 70, 60 and 50 mg/mL of the extract were evaluated on the inhibition of egg hatching (IEH) of HC. The hydroalcoholic extract of L. leucocephala showed 71% IEH at 100 mg/mL, an EC50 and EC90 of 52.22 and 302 mg/mL, respectively. The hydroalcoholic extract of L. leucocephala leaves contains bioactive compounds (phenolics, terpenes and flavonoids) that inhibit HC egg hatching with dose-dependent effect. Therefore, EHLL could be considered as an alternative control on this nematode, however, it is necessary to determine the specific metabolite that confers the activity, determine its toxicity and perform in vivo assays. [ABSTRACT FROM AUTHOR]

Background: The limited ovicidal activity of currently available acaricides is a significant obstacle to efficacious scabies treatment. Several essential oils or their respective components have proved to be active against the eggs of arthropods, mainly lice and ticks. Information on the activity of these oils and/or components against the eggs of mites remains very limited. The aim of this study was to assess the activity of six terpenes (carvacrol, eugenol, geraniol, citral, terpinen-4-ol and linalool) commonly found in essential oils against the eggs of Sarcoptes scabiei. Methods: Sarcoptes eggs were exposed to paraffin oil containing 1, 2.5, or 5% of each terpene tested. After a 12-h exposure period, the eggs were washed and placed in paraffin oil for hatching. Embryonic development following treatment was assessed every day to determine the stage of developmental arrest. Results: The median effective concentration to obtain 50% egg mortality (EC50) was 0.5, 0.9, 2.0, 4.8, 5.1 and 9.8% for carvacrol, eugenol, geraniol, citral, terpinen-4-ol and linalool, respectively. The microscopic images of eggs after each treatment indicated that these six terpenes may act by penetrating through the aeropyles on the egg surface. Conclusions: In conclusion, carvacrol, eugenol and geraniol possess significant ovicidal activities, which should be considered as promising ovicidal agents for the treatment of scabies. [ABSTRACT FROM AUTHOR]

Anacyclus pyrethrum Lag. is a medicinal plant. In this study we evaluated the susceptibility of larvae of Aedes aegypti Linn. against potential larvicidal effects of root extract of A. pyrethrum. Bioassays were performed using World Health Organization methodologies. GC-MS analysis was employed to determine the contents of the extract. The underlying mechanisms of larvicidal activity were analyzed by using morphological, histological, and Reactive Oxygen species (ROS) studies. The GC-MS of A. pyrethrum root extract showed nine compounds. During initial screening, the root extract killed 90% of 3rd instar larvae of A. aegypti at 0.2 mg/mL concentration as compared to standard permethrin. Different larval stages exhibited 100% larvicidal activity, especially more naive 1st and 2nd instar larvae. The dose dependent larvicidal activity against 3rd instar larvae, showed reduced effect with decreased concentration. Disruption in gut line of 3rd instar larvae is proposed to be mediated from the ROS production, evident in fluorescent oxidant sensitive assay. The extract exhibited non-cytotoxic profile in brine shrimp lethality assay with IC50 of 126.93 ± 0.3 µg/mL as compared to standard etoposide i.e., IC50 = 7.46 ± 0.05 µg/mL. The study inferred that the root extract of A. pyrethrum can serve as promising biopesticide for the control of A. aegypti, which is a vector of many viral diseases. [ABSTRACT FROM AUTHOR]

Background: The use of plant-based formulations is an easy and economical method to control insect pests. The objectives of the present study were to evaluate ovicidal and larvicidal potential of ethanolic leaf extracts of four plants, Cyathocline purpurea, Blumea lacera, Neanotis lancifolia, and Neanotis montholonii, and their effects on gut histology of Aedes aegypti (Diptera: Culicidae) larvae. We identified the phytochemicals present in the ethanolic extracts of these plants by LC-MS analysis. The eggs and larvae of A. aegypti were exposed to four concentrations (0.05, 0.1, 0.2, and 0.3 mg/mL) of crude ethanol extracts for different time durations. We observed egg hatching for 48 h, mortality, and gut histology of the 3rd instar larvae after 24, 48, and 72 h of treatments. Results: LC-MS analysis revealed the presence of various active compounds such as alkaloids, tannins, saponins, and flavonoids in the ethanol extracts of all these plants. The extracts of all plants showed ovicidal activity. The extracts of C. purpurea showed the highest larvicidal activity (LC50 at 72 h = 0.088 mg/mL) followed by B. lacera (LC50 at 72 h = 0.758 mg/mL) while N. lancifolia and N. montholonii extracts did not show significant larvicidal activity. All plant extracts affected gut morphology in concentration and treatment duration-dependent manner. The plant extracts used in the present study have ovicidal properties and affected the gut histology of A. aegypti larvae. Conclusion: These results suggest that C. purpurea has the highest larvicidal activity against A. aegypti larvae and can be further evaluated for application purposes. [ABSTRACT FROM AUTHOR]

Pulses have 20-27% proteins which is 2- 3 times higher than traditional cereals. These constitute the main source of proteins for developing countries, like India where per capita consumption of the animal protein is low, thus they are rightly considered the poor man’s meat. India is largest pulse consumer, importer and producer country of the world occupying an area of 228.47 lakh hectares with the production of 17380 million tones every year. With the United Nations declaration of 2016 as International Year of Pulses to replace the social evil of malnutrition by legume, the research pertaining to the biology and bio intensive management of bruchids pests has become increasingly important. Therefore, laboratory bioassay of essential oils which are regarded as “Green Chemicals” extracted from Zanthoxylum armatum DC., Rabdosia rugosa Wall. ex Benth, Artemisia maritima Linn. and Colebrookea oppositifolia Sm. by hydro distillation was carried out against Callosobruchus analis (F.) to evaluate biopesticidal potential in terms of oviposition and progeny deterrence and ovicidal activities. There was a significant difference in the number of eggs laid on treated and control sets and among the different treatments of essential oils. Z. armatum at 100 µl/ml allowed the bruchid to lay only 19.15±3.6 eggs as compared to 82.35±4.5 in control and proved to be most effective treatment with 76.74% oviposition deterrence. R. rugosa and A. maritima oil were found most effective in reducing the egg hatchability to 48.00±3.2 and 49.52±2.2% respectively at a lowest dose of 10 µl/ml. Egg hatching inhibition percentage increased with an increase in concentration of all the treatments. R. rugosa oil at 100 µl/ml proved to be most effective in reducing the adult emergence with 85.48% progeny deterrence followed by A. maritima showing 81.67% deterrence. All the tested essential oils revealed a wide range of bioactivities against the bruchid pest.

Background: Fasciolosis is an important zoonotic disease affecting the productive performance of farm animals in Egypt. Aim: The aim of the present study was comparing the ovicidal effect of different extracts as an alcoholic (Methanolic and Ethanolic) and aqueous Moringa oleifera leaf extracts on Fasciola gigantica non-embryonated and developed eggs. Materials and Methods: Tested concentrations of extracts ranged from 12.5 to 800 mg/ml. Nitroxynil was used as reference drug with a dose of 100 mg/ml. Results: M. oleifera alcoholic and aqueous extracts showed a concentration-dependent ovicidal effect on F. gigantica non-embryonated and developed eggs. Based on LC50 values, water extract showed the highest ovicidal activity since it registered the lowest values of 2.6 mg/ml on non-embryonated eggs. Non-embryonated eggs were more susceptible to aqueous extract than developed eggs. On the other hand, the developed eggs were more susceptible to ethanolic extract than non-embryonated eggs even the lowest LC50 (12.38 mg/ml). Conclusion: M. oleifera leaf extracts especially aqueous extract could be a promising step in the field of controlling fascioliasis. Further, in vivo studies are needed to enlighten the therapeutic potential of M. oleifera extracts in treating F. gigantica infection.

Essential oils and their components represent an appealing alternative strategy against parasitic mites. The chemical complexity and variability of essential oils limit their use and additional work is required to analyze the efficacy and application rate of essential oils' individual components. In the present study, the activity of five terpenes (terpinen-4-ol, citral, linalool, eugenol, and geraniol) was evaluated against Psoroptes cuniculi motile stages and eggs collected from naturally infected rabbits. Eugenol presented the best acaricidal efficacy with a median lethal concentration (LC50) value of less than 0.1% at 24 h, followed by geraniol (0.33%), linalool (0.38%), citral (0.46%), and terpinen-4-ol (0.66%). Geraniol and eugenol were able to kill all mites within 5 min at 1% concentration. The effective concentration to inhibit 50% (EC50) of egg hatching was 0.65%, 0.66%, 0.85%, 1.47%, and 2.87% for eugenol, geraniol, citral, terpinen-4-ol, and linalool, respectively. In conclusion, eugenol, geraniol, citral, terpinen-4-ol, and linalool should be considered as promising agents for the development of botanical acaricides against Psoroptes cuniculi. [ABSTRACT FROM AUTHOR]

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Recently, donkeys have gained popularity mainly due to the use of donkey milk by the cosmetic industry and for human consumption. Gastrointestinal strongyles (GIS) are considered a potential cause of disease and reduced production in infected donkeys. European laws limit the use of anthelmintic drugs for the control of GIS in dairy donkey farms, thus the need to develop alternative control methods. This study aimed to test the in vitro inhibiting effects of three chitin degrading fungi (Scopulariopsis brevicaulis, Metarhizium anisopliae, and Beauveria bassiana) on the hatch and viability of donkey GIS eggs by using the egg hatch test, and to compare their activity to that of Pochonia chlamydosporia. About 150 eggs were added to 0.5 mL of sterile saline solution containing about 1.4 x 108 spores of each fungal species or with 0.5 mL of sterile saline solution only (untreated controls). After incubation, the percentage of egg hatch reduction was calculated, and data were statistically analyzed. All fungi were able to significantly reduce (p < 0.05) the hatch of GIS eggs compared to the untreated controls. Further studies that aim to investigate the efficiency of these fungi in reducing donkey GIS eggs in contaminated environments are encouraged. [ABSTRACT FROM AUTHOR]

This study evaluated the larvicidal activity, and ovicidal activity of Origanum vulgare EO and its major components against the cotton bollworm, Helicoverpa armigera. The chemical composition of the O. vulgare EO was analyzed by gas chromatography-mass spectroscopy. GC-MS analysis revealed that the O. vulgare EO was composed of ten compounds. The major constituents were carvacrol (78.35%), followed by p-cymene (6.85%) and γ-terpinene (3.70%). In larvicidal activity assay, the O. vulgare EO achieved a LC50 value of 265.51 μg/ml. The three major constituents from the O. vulgare EO were tested individually for toxicity against larvae of H. armigera. Carvacrol, p-cymene, and γ-terpinene appeared to be most effective against H. armigera, with LC50 values of 51.53, 121.32, and 150.15 μg/ml, respectively. Moreover, EC50 values of carvacrol, p-cymene, and γ-terpinene against H. armigera eggs were 33.48, 47.85, and 56.54 μg/ml, respectively. Overall, this study showed that O. vulgare EO and its major constituents have the potential to develop as new eco-friendly insecticides against H. armigera. [ABSTRACT FROM AUTHOR]

The water-soluble Moringa oleifera lectin (WSMoL) exhibits larvicidal, ovicidal, and oviposition-stimulant effects on Aedes aegypti. Here, we evaluated the influence of gamma irradiation on the activity of WSMoL against A. aegypti. Irradiation with 10 mGy and 10 Gy did not result in the loss of protein molecules; however, irradiated samples presented a distinct profile on gel filtration chromatography. Bis-ANS probe fluorescence was similar when incubated with non-irradiated and 10 mGy-irradiated samples, but less intense fluorescence was observed when incubated with 10 Gy-irradiated WSMoL, indicating the exposure of lectin hydrophobic pockets to water. Irradiation of WSMoL with 10 mGy potentiated its larvicidal and ovicidal activities, while irradiated WSMoL with 10 Gy did not affect the survival of larvae and eggs. The stimulation of oviposition by WSMoL was not observed with irradiated samples. Nevertheless, the hatching rate of eggs laid on vessels containing 10 mGy-irradiated lectin (37%) was lower than that in vessels containing non-irradiated WSMoL (59%). In conclusion, a low dose of gamma irradiation (10 mGy) can be used to improve the deleterious effects of WSMoL on A. aegypti larvae and eggs, while a higher dose (10 Gy) was found to impair the insecticidal effects on this mosquito. These changes are probably linked to conformational changes in the structure of WSMoL. • The lectin WSMoL was exposed to gamma radiation at 10 mGy and 10 Gy. • There was no loss of protein molecules but conformational change was detected at 10 Gy. • Irradiation of WSMoL with 10 mGy potentialized larvicidal and ovicidal activities on A. aegypti. • Hatching of eggs laid on 10 mGy-irradiated lectin solution was lower than in non-irradiated WSMoL. [ABSTRACT FROM AUTHOR]

Nanotechnology is a relatively new field which is making advancements each day. It is making a huge impact on our day-to-day lives. Nanoparticles possess unique properties which makes it viable to use it in a wide variety of fields such as in cosmetics, parasitology and catalysis. We used a plant-mediated, nature-friendly method which does not involve the usage of any harmful chemicals. Syzgium cumini seed extract was taken as the reducing agent for the preparation of zinc oxide nanoparticles. Green-synthesized zinc oxide nanoparticles were confirmed using X-ray diffraction, Fourier-transform infrared, UV–Vis spectroscopy, scanning electron microscope and transmission electron microscope. The average particle size was found to be around 50–60 nm. Additionally, larvicidal and ovicidal activity of the prepared nanoparticles against dengue causing vector was also carried out which resulted in LC50 and LC90 of 51.94 ppm and 119.99 ppm, respectively. [ABSTRACT FROM AUTHOR]

The objective of this work is eco-friendly synthesis of Carbon/Copper oxide nano composites (C/CuO nano composites) from the aqueous extract of Aristolochia bracteolata (ABLPAE) via response surface methodology (RSM). Here we optimized various parameters to find out the absorption maximum value using RSM technique. Then the synthesized C/CuO nano composites were processed using different analytical tools. The crystanality of C/CuO was investigated using XRD analysis which exhibited crystalline size of 43 ± 2 nm. Additionally, synthesized C/CuO nano composites were used to study larvicidal activity using MANOVA; LSD-DMRT test. We found that results showed LC50 value at 26.42 ppm and 86.13 ppm for LC90. Ovicidal activity by anti-feedant method resulted in a dose dependent manner with a high mortality rate at higher concentrations. [ABSTRACT FROM AUTHOR]

Chemical and synthetic insecticides used for controlling Spodoptera litura (Fab.) resulted in the development of resistance to several classes of insecticides. In the present study, five organic products including cow urine, panchagavya, darekastra, agneystra, dashaparni, neem seed kernel extract (NSKE) and one biopesticide i.e., Neem Baan 1500 ppm were evaluated for their ovicidal activity at different concentrations against Spodoptera litura under laboratory conditions. Maximum ovicidal activity of 100 per cent was recorded by NSKE (at 10%) and Neem Baan 1500 ppm (at 0.15 and 0.30%) followed by darekastra (61.93 at 80% conc.). The study indicated that all the test products have variable ovicidal properties and may be used for the pest control at the time of appearance of the pest. [ABSTRACT FROM AUTHOR]

In developing countries, crop deterioration is mainly caused by inappropriate storage conditions that promote insect infestation. Synthetic pesticides are associated with serious adverse effects on humans and the environment. Thus, finding alternative “green” insecticides is a very pressing need. Calotropis procera (Aiton) Dryand (Apocynaceae) growing in Saudi Arabia was selected for this purpose. LC-MS/MS analysis was applied to investigate the metabolic composition of different C. procera extracts. Particularly, C. procera latex and leaves showed a high presence of cardenolides including calactin, uscharidin, 15β-hydroxy-calactin, 16β-hydroxy-calactin, and 12β-hydroxy-calactin. The ovicidal activity of the extracts from different plant organs (flowers, leaves, branches, roots), and of the latex, against Cadra cautella (Walker) (Lepidoptera, Pyralidae) was assessed. Extracts of C. procera roots displayed the most potent activity with 50% of C. cautella eggs not hatching at 10.000 ppm (1%).

Recently, donkeys have gained popularity mainly due to the use of donkey milk by the cosmetic industry and for human consumption. Gastrointestinal strongyles (GIS) are considered a potential cause of disease and reduced production in infected donkeys. European laws limit the use of anthelmintic drugs for the control of GIS in dairy donkey farms, thus the need to develop alternative control methods. This study aimed to test the in vitro inhibiting effects of three chitin degrading fungi (Scopulariopsis brevicaulis, Metarhizium anisopliae, and Beauveria bassiana) on the hatch and viability of donkey GIS eggs by using the egg hatch test, and to compare their activity to that of Pochonia chlamydosporia. About 150 eggs were added to 0.5 mL of sterile saline solution containing about 1.4 × 108 spores of each fungal species or with 0.5 mL of sterile saline solution only (untreated controls). After incubation, the percentage of egg hatch reduction was calculated, and data were statistically analyzed. All fungi were able to significantly reduce (p < 0.05) the hatch of GIS eggs compared to the untreated controls. Further studies that aim to investigate the efficiency of these fungi in reducing donkey GIS eggs in contaminated environments are encouraged.

The ovicidal potential of a diatomaceous earth based formulation Protect-it® was assessed against eggs of the date moth Ectomyelois ceratoniae. Three doses were tested: 50, 100 and 200 mg/kg. Hatching data showed a high sensitivity of the date moth eggs to the diatomaceous earth based formulation and a clear dose-response relationship was observed. For the doses 50, 100 and 200 mg/kg, the respective egg hatching rates were 25, 16 and 3% against 83.33% for the control. Moreover, the percentages of emergence of adults coming from treated eggs were respectively 2, 10 and 20% for the doses 200, 100 and 50 mg/kg against 73.32% for the control. Additionally, results indicated that the diatomaceous earth based formulation exhibited an ovicidal toxicity with corresponding LD50 and LD95 values of 0.019 and 1.307 mg/kg, respectively. This work clearly indicates the interest in the use of diatomaceous earth and its formulations as an alternative for controlling stored date pests.

Background: Head lice infestation is an important public health problem worldwide. Chemical pediculicides have lost their efficacy because lice have developed resistance to them. Therefore, alternative pediculicides such as essential oils and herbal products have been proposed for treating head lice infestation.Study Design: To determine the efficacy of essential oils from three Zingiberaceae plants (Curcuma xanthorrhiza, Curcuma zedoaria and Zingiber zerumbet) against head lice eggs and to investigate an augmenting substance (Eucalyptus globulus EO) for improving the efficacy of these essential oils in killing head lice eggs, especially on the inhibition of their hatching process. Permethrin pediculicide, soyabean oil, and drinking water were used as positive, negative, and neutral controls, respectively.Methods: An immersion test was used to evaluate the ovicidal activity of 12 essential oil formulations. Head lice eggs were immersed for 1, 5 and 10 min in the treatments. Mortality rate was observed on day 7 and day 14; mortality was checked under a stereomicroscope.Results: All head lice eggs that were immersed in a combination of 10% C. zedoaria EO and 10% E. globulus EO for 5 min did not hatch at all for 7-14 days of incubation. All head lice eggs that were immersed in soyabean oil and drinking water for 1, 5, and 10 min showed 100% hatching rate in 7-14 days of incubation. All head lice eggs that were immersed in permethrin pediculicide for 1, 5 min, showed 100% hatching rate, but when they were immersed for 10 min, permethrin provided 4.0-6.0% inhibition rate with 94.0-96.0% hatching rate for 7-14 days of incubation. All combinations of Zingiberaceae EOs and E. globulus EO at low and high concentrations (5 and 10%) exhibited high ovicidal activities against head lice eggs, and the combinations showed a synergistic effect with an increase in the inhibition rate of more than 50%.Conclusion: These results demonstrated that Zingiberaceae EOs augmented with E. globulus EO are promising ovicidal agents for head lice control. [ABSTRACT FROM AUTHOR]

Bioassays were conducted to determine the susceptibility of egg masses and young larvae of two pine processionary moth species, Thaumetopoea pityocampa and Thaumetopoea wilkinsoni, to two strains (ARSEF4556, V275) of the entomopathogenic fungus Metarhizium brunneum. Mortality of treated eggs by both strains ranged from 96% to 99% but not all of this was caused by M. brunneum since control groups also experienced egg mortality due to saprophytic fungi. Still, larvae hatched in the laboratory from eggs treated with M. brunneum were all killed by this fungus, acquiring M. brunneum conidia, whereas larval mortality was 0% in the control groups. Young larvae of both pine processionary moth species were also highly susceptible to ARSEF4556 and V275 with larval mortality ranging between 94% and 100%, 8 days post-inoculation, with the vast majority of larvae being killed within the first 2-4 days. Larval mortality was dose dependent. Results were consistent across the two pine processionary moth species, showing that the pathogenicity of M. brunneum to both eggs and young larvae might be promising for biological control of these insect pests. The study also showed that non-target parasitoids of pine processionary moth eggs were also susceptible to M. brunneum. Further work is required to understand and reduce the M. brunneum effect on non-target insects. [ABSTRACT FROM AUTHOR]

Background: Insect vector control is facing the challenges of resistance development and environmental hazards caused by synthetic pesticides. This has led to a considerable market opportunity for botanical insecticides. In this scenario, our study investigated the potential of selected bioactive monoterpenoids, carvacrol and thymol, as safe and effective tools to control the West Nile vector Culex pipiens. Furthermore, the combined effect of thymol-carvacrol mixtures and their possible interactions were assessed. Methods: For determining larvicidal and ovicidal 50% lethal concentration (LC50), each monoterpenoid was tested at different concentrations (5–500 mg/L). Then, the fixed ratio method was used for evaluating their combinational efficacy. Results: Carvacrol was more toxic against larvae of Cx. pipiens, with a LC50 value of 14 mg/L, whereas thymol exhibited a LC50 value of 49 mg/L. Comparable trends of efficacy were observed when toxicity on Cx. pipiens eggs was investigated, with LC50 values of 7 and 13 mg/L for carvacrol and thymol, respectively. In combinational toxicity assays, the mixture thymol-carvacrol at 1:4 ratio achieved a synergistic effect against larvae of Cx. pipiens, whereas an additive effect was observed on eggs. Other ratios showed antagonistic effects. Conclusions: Overall, our findings pointed out that the 1:4 ratio of thymol-carvacrol blend can enhance the insecticidal efficacy on Cx. pipiens young instars and can be considered further as active ingredient for developing botanical insecticides to be used in mosquito control operations.

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Based on the structural framework of a pyriproxyfen metabolite, nineteen oxime ester derivatives were synthesized via reaction of the carboxylic acids with 4-(2-(2-pyridinyloxy) ethoxy)benzaldehyde oxime. The corresponding structures were comprehensively characterized by 1H-nuclear magnetic resonance (NMR), 13C-NMR, and electrospray ionization high-resolution mass spectrometry (ESI-HRMS). All of the compounds were screened for their insecticidal activities against Plutella xylostella and Myzus persicae, and for their ovicidal activities against Helicoverpa armigera eggs. The results obtained show that most of the oxime ester derivatives displayed moderate to high insecticidal activities and ovicidal activities at a concentration of 600 μg/mL. In particular, the ovicidal activity of compounds 5j, 5o, 5p, 5q, and 5s was determined to be 100%. Importantly, some of the compounds presented even higher biological activities than the reference compound pyriproxyfen. For example, compound 5j displayed an insecticidal activity value of 87.5% against Myzus persicae, whereas the activity value of pyriproxyfen was 68.3% at a concentration of 600 μg/mL. Among the synthesized compounds 5j and 5s exhibited broad biological activity spectra. [ABSTRACT FROM AUTHOR]

Mosquitoes are insects of huge public health importance, since they act as vectors for important pathogens and parasites. Here, we focused on the possibility of using the neem cake in the fight against mosquito vectors. The neem cake chemical composition significantly changes among producers, as evidenced by our HPTLC (High performance thin layer chromatography) analyses of different marketed products. Neem cake extracts were tested to evaluate the ovicidal, larvicidal and adulticidal activity against the rural malaria vector Anopheles culicifacies. Ovicidal activity of both types of extracts was statistically significant, and 150 ppm completely inhibited egg hatching. LC50 values were extremely low against fourth instar larvae, ranging from 1.321 (NM1) to 1.818 ppm (NA2). Adulticidal activity was also high, with LC50 ranging from 3.015 (NM1) to 3.637 ppm (NM2). This study pointed out the utility of neem cake as a source of eco-friendly mosquitocides in Anopheline vector control programmes. [ABSTRACT FROM AUTHOR]

A fumigant toxicity tests were performed by using airtight plastic jars, in which five small glass tubes with perforated lids containing 20 cowpea seeds and four newly emerged Callosobruchus maculatus were placed. Filter paper impregnated with an appropriate volume (5, 10, 20, 40 µl/ml) of the oils were attached to the lower surface of the jar lid. Mortality counts were made at 6, 12, 24 and 48 h after treatment. For ovicidal activity, seeds having 20 eggs altogether were put in a glass vial and the treatments were followed as mentioned earlier. After 48 h of exposure the seeds with eggs were transferred and ovicidal activity was calculated based on the adult emergence. Among the essential oils tested, five oils, viz. camphor, eucalyptus, nutmeg and rosemary showed 100 % mortality even at lower dosages (5 µl) when adults were exposed for 48 h.Onthe other hand, seven oils showed 100% mortality at higher concentration (40 µl). Ovicidal activity revealed that 9 oils showed good activity against C. maculatus at higher concentrations. Among them four oils, viz. camphor, eucalyptus, rosemary and wintergreen showed 100 % egg mortality. In this work, it can be concluded that camphor, eucalyptus, nutmeg, rosemary, wintergreen oils showed very good fumigant and ovicidal activity. However, the possibility of utilising these plant oils to control C. maculatus in storage conditions may warrant further investigation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Plant extract mixtures were tested against the Asian spongy moth eggs. • Penetrating surfactant increased the toxicity of plant extract mixtures. • Ovicidal efficacy of plant extract mixture was enhanced with egg maturation. The Asian spongy moth (ASM, Lymantria dispar asiatica) is a destructive pest of forests, agricultural fields, and urban areas. Plant extract mixtures were evaluated as alternative tools for integrated pest management targeting the overwintering eggs of ASM. When formulated with an adjuvant able to penetrate the hairy egg mass, plant extract mixtures inhibited egg hatching. The extract mixture (cinnamon extract 5% + citronella oil 10% + citrus oil 30% + derris extract 10% + neem extract 20% + penetrating surfactant 25%) with the highest ovicidal activity (97.6% mortality) is a potential botanical insecticide for use against ASM eggs. Susceptibility to mortality from plant extract mixtures increased with egg maturation. Optimal timing for control of overwintering ASM eggs corresponded to the period in spring when larvae inside eggs were fully differentiated. These results will help improve control efficacy with a day-degree model that predicts egg hatch as well as future development nano-formulations. [ABSTRACT FROM AUTHOR]

The purpose of this work was to assess the ovicidal activity of Chrysosporium merdarium, Trichoderma harzianum, Fusarium oxysporum, F. moniliforme and F. sulphureum isolated from public areas in the city of La Plata, Argentina, on Toxocara canis eggs in vitro. Each species were cultured on water agar 2% with a suspension of immature-stage T. canis eggs. At 4, 7, 14, 21 and 28 days post-culture, they were observed by light and scanning electron microscopy. One hundred eggs were evaluated and scored according to Lỳsek’s ovicidal effect classification. These procedures were repeated three times which each fungal species. Chrysosporium merdarium and F. oxysporum showed very high ovicidal activity, F. sulphureum high ovicidal activity, F. moniliforme intermediate ovicidal activity and T. harzianum did not affect the viability of T. canis eggs. Taking into account the effects on human and animal health and the environment, the species with better prospects for studying its potential use as biological control was F. sulphureum.

Mosquitoes transmit serious diseases to humans and animals, causing millions of deaths every year. Effective insecticides of natural origin for eco-friendly vector control are a priority. In this study, silver nanoparticles (AgNPs) biosynthesized using as cheap Psychotria nilgiriensis leaf extract were tested on larvae and pupae of Aedes aegypti (Diptera: Culicidae). Biophysical characterization was carried out with UV–vis spectrophotometry, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Larvae were exposed to varying concentrations of aqueous extract of synthesized AgNPs for 24 h. The maximum mortality was observed for green-synthesized AgNPs. Moreover, the combined treatment of leaf extract of P. nilgiriensis and AgNPs lowered the plant extract LC 50 to 92.87, 115.27, 140.37, 169.30 and 212.55 μg/ml. The effectiveness of green synthesized AgNPs was confirmed against eggs and adults of A. aegypti . Furthermore, we showed that the predatory efficiency of Poecilia sphenops on A. aegypti was not reduced after the exposure at sublethal doses of AgNPs. Predation in the control was 65% (larva I) and 49.62% (larva II). Predation against late-instar larvae was minimal. In AgNPs-treated environment (3 ppm), predation was boosted to 90.25% (larva I) and 76.50% (larva II), respectively. Overall, P. nilgiriensis -synthesized AgNPs could be proposed at ultra-low doses to reduce larval population of dengue vectors enhancing predation rates of P. sphenops. [ABSTRACT FROM AUTHOR]

Currently phytochemical approach for the synthesis of metal nanoparticles plays a major role. In this manuscript phytochemical synthesis of Ni-Pd bi-metallic nanoparticles (Ni-Pd NPs) were subjected for various biological applications like pesticidal, larvicidal and ovicidal activities. The synthesized Ni-Pd NPs were confirmed by various characterization techniques, The XRD pattern confirms the formation of Ni-Pd NPs in purest crystalline form and it matches with the Joint Committee Powder Diffraction Standard data of JCPDS: 65-5788. The crystalline sizes of bi-metallic nanoparticles were found to be 33 nm which is calculated from Scherrer equation. TEM images clear cuts the spherical particle of Pd NPs with over layered by Ni NPs. The TEM histogram analysis helps to find the average particle size of Ni-Pd NPs as 34 ± 2 nm. The EDAX spectrum also confirms the presence of palladium and nickel atom. Further the synthesized bi-metallic nanoparticles were subjected for larvicidal activity against Aedes aegypti ( A. aegypti ) which resulted in LC 50 and LC 90 of 288.88 ppm and 483.06 ppm respectively. Also in this manuscript phyto-synthesized Ni-Pd NPs were subjected to antifeedant activity against Callosobruchus maculatus ( C. maculatus ) and ovicidal activity against eggs of C. maculatus were performed. [ABSTRACT FROM AUTHOR]

The fumigant action of four plant oils viz., garlic (Allium sutivumL.), clove [Syzygium aromaticum(L.) Merr. & Perry], attarasa [Litsea cubeba(Lour.) Pers.] and coriander (Coriandrum sativumL.) oils, was tested against eggs ofCallosobruchus chinensis(L.). After 72 h of exposure, garlic oil exhibited the highest fumigant toxicity against eggs ofC.chinensis, which was followed by clove, attarasa and coriander oils, with LC50values of 0.34, 1.12, 3.78 and 5.29 μL/L air, respectively. Binary mixtures of clove/coriander oil and clove/attarasa oil showed significant synergism with the co-toxicity factor of 241.77 and 114.15, respectively, while other combinations did not show any synergism. Optimal volume proportions of these synergistic combinations were 24:76 for clove/coriander oil and 41:59 for clove/attarasa oil, which were screened out with the toxicity index and were further confirmed by the co-toxicity coefficient. GC-MS analysis of these oils showed that eugenol, aceteugenol and β-caryophyllene were major components of clove oil, linalool, α-pinene, camphor, geranyl acetate and γ-terpinolene of coriander oil, α-citral, β-citral, D-limonene, linalool and sulcatone of attarasa oil, and sulphur compounds of garlic oil. Based on high toxicity againstC.chinensiseggs and synergistic action of plant oil mixtures, clove oil can be used as another potential grain fumigant for the management of stored legume pests. [ABSTRACT FROM AUTHOR]

Anthelmintic resistance in livestock parasites is currently a worldwide problem. Fasciola hepatica is a cosmopolitan parasite which causes considerable loss in sheep and cattle production systems all over the world. Chemotherapy is currently the main tool available for its control. The intensive use of triclabendazole, the drug of choice for more than 20 years, has resulted in the development of resistant strains. The therapeutic options are adulticides such as closantel (salicylanilide anthelmintic that binds extensively to plasma albumin) to treat chronic fascioliasis in sheep, and cattle. In the present work, an Egg Hatch Assay (EHA) and morphometric studies were used to evaluate in vivo the ovicidal activity and morphology F. hepatica eggs, recovered from closantel treated sheep collected at different time intervals post treatment. Statistically significant differences (p < 0.0001) were observed in egg morphometry between the control and the treated groups in all the parameters studied. Eggs recovered from treated animals tend to be narrower and longer. Significant differences were found in the embryonation and hatching of eggs between 36 h post treatment (32, 5%) vs. approximately 85% in control, 12 h and 24 h post treatment. Our results confirm that closantel affects in vivo the normal development of the eggs. As one of the first effects, this drug affects the performance of the trematode's reproductive physiology. Even though closantel treated animals may still eliminate eggs in the first days post treatment, these are not viable. [ABSTRACT FROM AUTHOR]

To introduce ecologically safe acaricide, effects of essential oils derived from Cuminum cyminum (Cumin), Syzygium aromaticum (Clove), and Mentha spicata (Spearmint) were determined on Tetranychus urticae at 25±1°C, 65±5% RH and a photoperiod of 16:8 (L:D) hour. The essential oils extracted by hydro-distillation were characterized by means of GC and GC-MS. Bioassays were performed by filter paper diffusion without allowing direct contact. Cumin, clove, and spearmint oils contained α- Pinene (29.1%), eugenol (78.5%) and carvone (59.4%), respectively, as the major compounds. The lowest LC50 value for adults was recorded for cumin oil (3.74 μL L-1 air) followed by clove (6.13 μL L-1 air) and spearmint (7.53 μL L-1 air). The highest ovicidal activity was recorded for cumin oil (LC50 = 7.65 μL L-1 air) followed by clove (LC50 = 8.73 μL L-1 air) and spearmint (LC50 = 9.01 μL L-1 air). According to repellency tests, by increasing concentration of oils, the repellency effects were increased. The most potent repellency effect was recorded for clove, followed by spearmint and cumin oils. The three extracted essential oils seem to be suitable sources of active vapors that can be used as alternatives for chemical pesticides for controlling this pest. [ABSTRACT FROM AUTHOR]

Little is known about the ovicidal effects of fungi that attack nymphs and adults of triatomine vectors. A combined formulation of Metarhizium anisopliae IP 46 conidia prepared with diatomaceous earth ( DE) and vegetable oil was tested against eggs of Triatoma infestans. Eggs were highly susceptible to fungal infection at relative humidity close to saturation [>98% relative humidity ( RH)] but not at 75% RH regardless of the formulation applied. Susceptibility of eggs decreased with longer post-ovipositional embryonation periods before treatments. The eventual eclosion of nymphs was best suppressed by application of conidia prepared with DE + oil and at a >98% RH incubation. Moreover, nymphs were less affected by the fungus when exposed for only a 24-h period after eclosion to a treated surface than individuals that were in constant contact with the conidia. These findings contribute to a better understanding of the potential of M. anisopliae as an agent against all developmental stages of T. infestans. [ABSTRACT FROM AUTHOR]