Percentage Egg Hatch Research Articles

Determining the Sterilization Doses under Hypoxia for the Novel Black Pupae Genetic Sexing Strain of Anastrepha fraterculus (Diptera, Tephritidae).

Simple SummaryThe sterile insect technique is an environmentally-friendly method that can be used to manage populations of the South American fruit fly Anastrepha fraterculus, but its sterilizing doses have been determined only under normoxia. To maintain sterile male fly quality without jeopardizing sterility, a strategy of applying the radiation dose under an oxygen-reduced atmosphere is commonly used. Therefore, this study tested a range of gamma radiation doses under hypoxia on pupae from a bisexual strain and a novel genetic sexing strain (GSS) of A. fraterculus. Four types of crosses between irradiated flies under hypoxia and nonirradiated flies of the bisexual strain were set to assess sterility for each strain and radiation dose. For males from both strains, the effect of radiation dose on the percentage of egg hatch, egg-to-pupa recovery, and recovery of adults were determined. A dose of 74 Gy reduced egg hatch by 99% regardless of the male strain and was considered the sterilizing dose. The fertility of irradiated females and development of their offspring were severely affected, even at low doses under hypoxia, and no eggs were laid with doses above 50 Gy.A common strategy used to maintain sterile fly quality without sacrificing sterility is to irradiate the insects under an oxygen-reduced atmosphere. So far, sterilizing doses for the South American fruit fly Anastrepha fraterculus have only been determined under normoxia. Our study reports for the first time the dose-sterility response under hypoxia for two different A. fraterculus strains. The pupae were derived from a bisexual strain (a Brazilian-1 population) and a recently developed genetic sexing strain (GSS-89). Two hours prior to irradiation, pupae were transferred to sealed glass bottles and irradiated when oxygen concentration was below 3%. Four types of crosses with nonirradiated flies of the bisexual strain were set to assess sterility for each radiation dose. For males from both strains, Weibull dose–response curves between radiation doses and the proportion of egg hatch, egg-to-pupa recovery, and recovery of adults were determined. The GSS males revealed high sterility/mortality levels compared to males from the bisexual strain at doses < 40 Gy, but a dose of 74 Gy reduced egg hatch by 99% regardless of the male strain and was considered the sterilizing dose. The fertility of irradiated females was severely affected even at low doses under hypoxia.

Evidence-based investigations into the ethnoveterinary use of Mimosa pudica L. (Fabaceae) as an anthlemintic

Purpose: To investigate the toxicity, clinical outcome and anthelmintic effects of M. pudica in vitro and in vivo.Methods: Dried leaves of M. pudica were extracted using 70 % methanol cold maceration method. Acute toxicity inquiry was evaluated using Lorke’s method. Anthelmintic effects were investigated in vitro using the egg hatch assay and in vivo using Heligmosomoides bakeri experimentally infected adult albino mice. Coprological and haematological parameters were recorded during the experiment while the serological analysis and post mortem worm burden were assessed at the conclusion of the research.Results: No mortality was recorded in oral acute toxicity test up to a dose of 5000 mg/kg. A probit-log analysis of the percentage egg hatch of the extract and albendazole gave lethal concentration 50 (LC50) values of 1.160 and -1.042, respectively. A reduction in worm count was observed in all the extracttreated groups post mortem, with the maximum extract group having the least worm count (p &lt; 0.05). Treatment with extract resulted in improvement in the haematological parameters. Serum chemistry revealed no significant differences (p &gt; 0.05) in alanine aminotransferase and blood urea nitrogen in all groups. However, a dose-dependent increases in the total protein and albumin was observed.Conclusion: These results show that although M. pudica has weak anthelmintic effects compared to albendazole (standard anthelmintic), in vivo and in vitro, at the doses used in this study, nonetheless, it reduces worm burden and improves haematologic parameters, serum total protein, albumin and overall weight gain of the treated mice. Thus, increased doses may be effective in anthelmintic chemotherapy.&#x0D; Keywords: Mimosa pudica, Anthelmintic, Toxicity, Heligmosomoides bakeri, Ethnoveterinary medicine, Anthelmintic

Lethal and sublethal effects of the insecticides d-limonene, mineral oil, and potassium salts of fatty acid on Dactylopius Opuntiae potential predator Cryptolaemus Montrouzieri

In the last few years, Dactylopius opuntiae has seriously harmed the cactus pear in Morocco. Chemical control and predators are presently the predominant method used to control this scale pest. In this study the lethal and sublethal effects of the insecticides: d-limonene (60 g/l) 150 cc/hl, mineral oil (780 g/l) 2400 cc/hl, and potassium salts of fatty acid (500 g/l) 40 cc/hl on Cryptolaemus montrouzieri (mealybug destroyer) were evaluated under laboratory conditions at 26±2°C, 60±10 % RH and 12:12 h L:D regime. The results of this study show that potassium salts of fatty acid (500 g/l) 40 cc/hl seems to be less compatible with C. montrouzieri. This chemical insecticide was decreased oviposition period, adult longevity, fecundity, significantly decreased females fertility compared to other treatments, caused a high percentage of mortality for all larval stages and pupa compared to all other treatments tested, caused significant reductions in percentage of egg hatching, and decreased significantly the longevity of adult stage compared to others treatments. Mineral oil (780 g/l) 2400 cc/hl seems to be most compatible with C. montrouzieri. This biological insecticide does not affect significantly the females fertility and does not cause any significant reduction in percentage of egg hatching (100 %) compared to the control treatment. In addition, d-limonene (60 g/l) 150 cc/hl, and mineral oil (78 %) 2400 cc/hl treatments do not affect significantly long term population parameters, including T, rm, λ, and DT compared to control treatment. Thus, both biological insecticides mineral oil (780 g/l) 2400 cc/hl and d-limonene (60 g/l) 150 cc/hl could be used as part of the integrated pest management strategy using C. montrouzieri and more attention should be paid to the use of chemical insecticide potassium salts of fatty acid (500 g/l) 40 cc/hl.

Antiparasitic potentiality of ethanol and methanol extracts of Azadirachta indica leaf for eggs and copepodid stage of Argulus japonicus: in vitro study.

In the present study, eggs and copepodid stages of Argulus japonicus were treated with ethanol and methanol extract of Azadirachta indica (neem) leaf and its antiparasitic efficacy (AE %) was determined. The experiments were performed in triplicate along with the positive (2% DMSO) and negative (without DMSO and extract) control groups. The reduced cumulative hatching percentage of eggs by 13% (in ethanolic) and 17% (in methanolic) extract of neem leaf at 1.5g L-1 was obtained during 15-day exposure compared to the control group showing 70-85% eggs hatching. The AE of 100% for ethanolic and 91.66% for methanolic extract against the copepodid stage was found at 1.25 and 1.5g L-1 respectively in 6h. The histological analysis of the eggs showed the undifferentiated decaying mass of cells with extensively damaged eggs when treated with ethanolic extract of neem leaf. Further, severe degeneration in the branchial region, digestive tract and eye cells was observed in the copepodids treated with ethanol extract than the methanol extract. The terpenoids a potential antiparasitic compound of ethanolic extract produced more AE than the methanolic extract. Thus, the ethanolic extract of neem leaf can be potentially utilized as a natural parasiticide to disrupt the egg and other life phases of A. japonicus.

Comparison of the Hatch of Newly Laid Lycorma delicatula (Hemiptera: Fulgoridae) Eggs From the United States After Exposure to Different Temperatures and Durations of Low Temperature.

Comparisons were made of the effects of temperature and duration of low temperature on hatch of newly laid egg masses of the invasive spotted lanternfly, Lycorma delicatula (White). Egg masses were collected in mid-October 2019 and estimated to be less than 14 d old. There was a significant positive nonlinear relationship between temperature and developmental rate (1/d) for eggs held at constant temperatures. The lower threshold for egg development was estimated as 7.39°C. Eggs held at constant 10, 15, and 20°C were estimated to require 635, 715, and 849 DD7.39, respectively, to develop. Egg hatch was variable, egg hatch rates were highest (58.4%) when held at a constant 15°C, though high rates (52.7%) were also obtained when eggs were held for 84 d at 10°C, then moved to 25°C. Almost all eggs enter diapause since very few eggs were able hatch when moved to 25°C after 7 d of chill at either 5 or 10°C. Chilling at 5 or 10°C increased percentage egg hatch as the duration in chill increased up to ~100 d and eggs held at 10°C were able to complete some or all the post-diapause development before being moved to 25°C. All egg masses were held at constant 16:8 (L:D) photoperiod and 65%RH. Our data suggest that temperature is the driving factor for diapause termination in spotted lanternfly, but other abiotic factors should be investigated. These identified developmental temperature threshold and degree day requirements for egg hatch will improve predictive distribution and phenological models.

Impact of mycolactone produced by Mycobacterium ulcerans on life-history traits of Aedes aegypti (L.) and resulting habitat selection for oviposition.

Buruli ulcer (BU) is a globally recognized, yet largely neglected tropical disease whose etiologic agent is Mycobacterium ulcerans. Although the exact mode of transmission is unclear, epidemiological evidence links BU incidence with slow-moving or stagnant, aquatic habitats, and laboratory-based experiments have shown disease manifestation in animals with dermal punctures. Therefore, hypotheses for transmission include contact with slowmoving aquatic habitats and associated biting aquatic insects, such as mosquitoes. Recent research demonstrated the toxin produced by M. ulcerans, mycolactone, is an attractant for adult mosquitoes seeking a blood-meal as well as oviposition sites. In the study presented here, we examined the impact of mycolactone at different concentrations on immature lifehistory traits of Aedes aegypti, which commonly occurs in the same environment as M. ulcerans. We determined percent egg hatch was not significantly different across treatments. However, concentration impacted the survivorship of larval mosquitoes to the adult stage (p < 0.001). Resulting adults also showed a slight preference, but not significant (p > 0.05), for oviposition in habitats contaminated with mycolactone suggesting a legacy effect.

Effects of UV Radiation on Egg Hatching Population Growth and Reproductive Parameters of Indianmeal Moth Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae)

In this research, three age groups of Plodia interpunctella (Hübner) eggs (1-, 2- and 3-day-old eggs) were exposed to ultraviolet irradiation (UVC) with 254nm wavelength for 0.5, 1, 1.5, 2, 4, 8, 16, 24, 32 and 40 minutes, under controlled conditions. The effect of UVC-irradiation on reproduction and population growth parameters investigated for eggs irradiated for 0.5, 1 and 1.5 minutes. The percentage of egg hatching decreased with increase in UVC exposure time, while for each exposure time, the older eggs were more sensitive than the younger ones. The results indicated that different exposure times of UVC-irradiation could affect the reproduction and population growth parameters. The highest value of net fertility rates was observed in 1, 2 and 3-day-old eggs which were treated with 0.5 min exposure. Both the intrinsic rate of increase (rm) and the net reproductive rate (R0) decreased with increasing exposure time from 0.5 to 1.5 min while the mean generation time (Tc) and doubling time (DT) increased within this irradiation range. The lowest amount of rm was obtained in 1, 2 and 3-day-old eggs which were treated with 1.5 min exposure time. The results showed that UVC-irradiation is an appropriate technique for controlling P. interpunctella.

Artificial Larval Diet Mediates the Microbiome of Queensland Fruit Fly.

Larval diets used for artificial rearing can have a significant effect on insect biology. The Queensland fruit fly (aka “Qfly”), Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), is one of the greatest challenges for fruit growers in Australia. The sterile insect technique (SIT) is being developed to manage outbreaks in regions that remain free of Qfly and to reduce populations in regions where this species is endemic. Factory scale rearing is essential for SIT; however, artificial larval diets are known to affect the microbiome of Qfly, which may then affect fly performance. In this study, high-throughput Illumina sequencing was used to assess the Qfly microbiome in colonies reared, for five generations from nature, on two common artificial diets (carrot and gel). At generation five (G5), the microbiome was assessed in larvae, pupae, adult males and adult females and standard fly quality control parameters were assessed together with additional performance measures of mating propensity and survival under nutritional stress. At the genus level, bacterial communities were significantly different between the colonies reared on the two larval diets. However, communities converged at Phyla to family taxonomic levels. Bacterial genera of Morganella, Citrobacter, Providencia, and Burkholderia were highly abundant in all developmental stages of Qfly reared on the gel diet, when compared to the carrot diet. Despite abundance of these genera, a greater percentage of egg hatching, heavier pupal weight and a higher percentage of fliers were found in the Qfly reared on the gel diet. Mating propensity and survival under nutritional stress was similar for adult Qfly that had been reared on the two larval diets. Overall, our findings demonstrate that the artificial larval diet strongly influences the microbiome and quality control measures of Qfly, with likely downstream effects on performance of flies released in SIT programs.

Parental Microbiota Modulates Offspring Development, Body Mass and Fecundity in a Polyphagous Fruit Fly.

The commensal microbiota is a key modulator of animal fitness, but little is known about the extent to which the parental microbiota influences fitness-related traits of future generations. We addressed this gap by manipulating the parental microbiota of a polyphagous fruit fly (Bactrocera tryoni) and measuring offspring developmental traits, body composition, and fecundity. We generated three parental microbiota treatments where parents had a microbiota that was non-manipulated (control), removed (axenic), or removed-and-reintroduced (reinoculation). We found that the percentage of egg hatching, of pupal production, and body weight of larvae and adult females were lower in offspring of axenic parents compared to that of non-axenic parents. The percentage of partially emerged adults was higher, and fecundity of adult females was lower in offspring of axenic parents relative to offspring of control and reinoculated parents. There was no significant effect of parental microbiota manipulation on offspring developmental time or lipid reserve. Our results reveal transgenerational effects of the parental commensal microbiota on different aspects of offspring life-history traits, thereby providing a better understanding of the long-lasting effects of host–microbe interactions.

Biomarkers Changes Induced in The Mediterranean Fruit Fly, Ceratitis capitata (Wied.) Irradiated by Sterilising And Substerilising Doses of Gamma Radiation

Radiation technology is widely used to produce changes in biosystems. The goal of this work is to determine the variation induced in male parents and F1 Ceratitiis capitata when gamma-irradiated as pupae using substerilising doses (50 and 70 Gy and sterilising dose 90 Gy. Biological studies showed that the percent adult emergence of irradiated pupae decreased as the dose increased and also the percent egg hatchability decreased as the dose increased, also percent pupation and percent emergence of F1 decreased as the dose increased. Comparing DNA (using RAPD-PCR) of untreated adults, adults irradiated with sterilising dose of 90 Gy and parents irradiated with substerile dose (50 and 70 Gy) and their resultant F1. The results revealed that some extra bands appeared and others disappeared, as a result of irradiation. The appearance of extra bands may be due to the repair mechanism of the irradiation damaged DNA. The banding patterns obtained and the dendrograms drawn on the basis of presence and absence of bands revealed that irradiation of parents with 50 and 70 Gy and their F1 are different from the unirradiated pupae It was concluded that the sterile male technique could be used as a benefit tool in controlling Ceratitiis capitata.

In Vivo and In Vitro Pharmacodynamics of Anthelmintic Medication Used in Sheep

Our research aimed to evaluate the efficacy of anthelmintic treatments in sheep, as well as the resistance occurrence risk for the most commonly used substances. Anthelmintic medication efficacy was evaluated on 30 animals from a private farm, located in Sânmihaiu Almaşului, Sălaj County. In vivo studies were performed by using Fecal Egg Count Reduction Test (FECRT) and testing an albendazole-based (ABZ) product. In vitro, we used Egg Hatch Assay (EHA) and Larval Development Assay (LDA) for albendazole (ABZ), mebendazole (MBZ), fenbendazole (FBZ), thiabendazole (TBZ) and ivermectin (IVM) (only for LDA). FECRT showed that intestinal nematodes developed resistance phenomena against the ABZ-based product, with an extensivity of 80% at seven days post therapy, an egg reduction percentage of 41.89% at seven days post-therapy and 43.9% at 14 days post-therapy. The in vitro EHA highlighted a superior efficacy of TBZ (egg hatch percentage at reference concentration being 51.21) compared to ABZ (71.89%), MBZ (84.46%) and FBZ (79.22%), with a minimum risk of anthelmintic resistance. The LDA test revealed the superior efficacy of FBZ (MIC 0.59 mcg/ml) and IVM (MIC 0.078 mcg/ml), with a minimal risk of inducing parasitic resistance. All in vivo and in vitro tests revealed a limited ABZ efficacy, recommending avoiding the therapy with this substance.

Male age affects female mating preference but not fitness in the monandrous mothDendrolimus punctatusWalker (Lepidoptera: Lasiocampidae)

AbstractIt is widely accepted that male age can influence female mating preference and subsequent fitness consequences in many polyandrous species, yet this is seldom investigated in monandrous species. In the present study, we use the monandrous pine mothDendrolimus punctatusto examine the effects of male age on female mating preference and future reproductive potential. In multiple male trials, when permitted free mating from an aggregation consisting of virgin males aged 0 (young), 2 (middle‐aged) and 4 (old) days, virgin females preferentially mate with young and middle‐aged males, although mating latency and mating duration are independent of male age. In single male trials, when virgin females are randomly assigned single virgin males of known age, a negative correlation is found between mating success and male age in this species. However, we find that male age also has no effect on mating latency and mating duration. Further fitness analysis reveals that females do not receive benefits in terms of oviposition period, total egg production, average daily egg production, percentage of egg hatching, longevity, expected reproduction and relative expected reproduction from mating with young and middle‐aged males compared with mating with old males. The results of the present study are the first demonstrate that females mated preferentially with younger males but gain no apparent fitness benefits in a monandrous moth species.

The effect of Neem oil in controlling Khapra beetle Trogoderma granarium (Dermestidae : Coleoptera) and reducing its associated fungal isolates in wheat grains

The khapra beetle, Trogoderma granarium is an important pest of stored wheat worldwide. The current study was carried out to evaluate the lethal and the sublethal three concentrations of neem oil on T. granarium. We also assessed the effect of neem oil on the growth of fungal species associated with T. granarium infected wheat grains. The results demonstrate that treating of wheat grains with 5% neem caused the highest mortality of T. granarium (82.3%). The results were also shown that application of neem oil decreased the percentage of weight loss of wheat grains and the percentage of egg hatching. In addition, the total number of fungal isolates associated with T. granarium infecting neem-treated wheat grains were 4 fungal isolates, compared to 13 fungal isolates from untreated wheat grains. The results demonstrate that neem oil has potential use as a biological control agents of T. granarium; however, further studies under commercial storage conditions are required.

Prophylactic efficacy of Boerhavia diffusa L. aqueous extract in toluene induced reproductive and developmental toxicity in Drosophila melanogaster

BackgroundEnvironmental exposure to toxicants poses high risk to develop reproductive and developmental chronic toxicity in man. Toluene is one of the commonest industrial agents whose exposure is attributed with potential to induce reproductive and developmental toxicity. Since they contaminate the immediate environment of air and water to which humans are exposed, its containment is of great public health importance. Conventional treatment modalities fail owing to the difficulty to detect these highly volatile agents in environment and human body. The peril of such hazardous exposures is evident only when irreversible structural and functional damages have incurred. In such instances, prevention gains an upper hand when compared to therapeutic interventions. Several natural compounds derived from medicinal herbs possess potential to curb toxicities induced by such xenobiotic agents. Among them Boerhavia diffusa Linn. is a widely distributed and common herb attributed with antitoxic potential and capability for antioxidant defence. A study was performed on the prophylactic efficacy of aqueous extract of B. diffusa in curbing toluene induced developmental toxicity in Drosophila melanogaster. MethodsThe study consisted of a preliminary phytochemical screening and HPTLC profiling of B. diffusa aqueous extract (BDAE). LC50 of toluene was assessed and a sublethal dose of 200ppm was fixed for the study. Four doses of BDAE; 25, 50, 100 and 200mg/ml designated as Low dose, medium dose 1, medium dose 2 and high dose was used for the study. The parameters used for the study included the determination of larval period, pupal period, percentage of egg hatching, morphometric analysis of egg, larvae, pupae and adults, fertility, fecundity, lifespan and levels of antioxidant enzymes such as catalase, glutathione-S-transferase and superoxide dismutase. ResultsThe phytochemical and HPTLC characters were as per the pharmacopoeial standards. LC50 of toluene was found to be 430ppm in this study. BDAE at medium dose 2 and high dose significantly prevented the deterioration of reproductive and developmental toxicity parameters of larval period, pupal period, percentage of egg hatching, morphometric characters of larva, pupa and adult, fertility, fecundity and lifespan in drosophila. Also the drug significantly elevated the levels of antioxidant enzymes. ConclusionToluene exposure during lifetime is inevitable. B. diffusa, equipped with its rich active ingredients prevented toluene induced developmental and reproductive toxicity in Drosophila. This medicinal herb provides a ray of hope in preventing environmental toxin induced reproductive and developmental toxicity.

Effect of some nanoparticles on the stages biology of the southern cowpea beetle Callosobruchus maculatus (Fab.) (Coleoptera:Bruchidae)

Nano particle of Zinc oxide size (5nm) and (100nm) and silver nano Particle (100 nm) were used in This study at concentrations (100, 250, 500, 750 and 1000) ppm to know their effect on some biological aspects of the southern cowpea beetle Callosobruchus maculatus (Fab.) through treating the food of these insects (chick pea seeds) by these nanoparticles. The study proved that the above Particles had a significant effect on the parentage of eggs hatching as it reached 49.4% compared to 86.9% of control Also, the some treatment led to high at 1000 ppm concentration mortality percentage 98%. Moreover, the treatment had an effect on the pupa stage and on the period of insect development, which was elongated significantly in the treatments of the zinc oxide size (100 nm). The maximum period was 40.60 days at the concentration of 1000 ppm Which differed significantly from its comparative coefficient. The productivity of insect decreased significantly to 16.6%in zinc oxide nano Particle size (5 nm) clearly. This study showed that the treatments effected the vitality of the first-generation females as the percentage of egg hatching decreased to 50% more than that egg retention was observed on these females which reached to 50% at treatment of zinc oxide size (5 nanometer).

Effect of alcoholic extract of the plant Nigella Sativa on viability of eggs and adults of the liver giant worm Fasciola gigantica In vitro.

The study aimed to examine the effect of Nigella sativa extract on viability of eggs and adults of Fasciola gigantica In vitro. N.sativa brought from local markt of Al-Najaf city while eggs and adults worm of the parasite collected from cows and buffaloes infected and in the abattoir of Al-Najaf city.Result showed a significant effect for extract in reducing of the percentage of egg hatching and increasing of the mortality percentage of adult worms compar with control groups.

Evaluating the effects of anticoagulants on Rhodnius prolixus artificial blood feeding.

Blood-sucking insects are responsible for the transmission of several important disease-causing organisms such as viruses, bacteria, and protozoans. The hematophagous hemipteran Rhodnius prolixus is one of the most important vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. Due to the medical importance of this insect, it has been used as a study model in physiology and biochemistry since the 1930s. Artificial feeding has been recognized as a feasible and a more ethical alternative method of feeding these hematophagous insects. To prevent clotting after blood collection defibrination or treatment with anticoagulants are necessary. Although anticoagulants have been routinely used for stabilizing the collected blood, there is a gap in demonstration of the effects of using anticoagulants on the feeding and development of the hematophagous insect Rhodnius prolixus. In this study, we compared the survival rate, molting efficiency, fertility, and infection development between insects that were fed on blood containing three different anticoagulants (citrate, EDTA, and heparin). We observed that fifth instar nymphs that were fed on blood containing EDTA and citrate could not perform digestion properly, which resulted in molting inefficiency. Adult insects that were fed on EDTA-containing blood laid lower number of eggs, and also had a diminished egg hatch percentage. When we delivered T. cruzi parasites in blood containing citrate or EDTA to the insects, a lower number of parasites and metacyclic trypomastigotes was observed in the intestine compared to the group fed on heparin-containing blood. Since heparin could potentially inhibit DNA polymerase activity in DNA samples extracted from the intestine, we analyzed different heparin concentrations to determine which one is the best for use as an anticoagulant. Concentrations ranging between 2.5 and 5 U/mL were able to inhibit coagulation without severely impairing DNA polymerase activity, thus indicating that this should be considered as the range of use for feeding experiments. Our results suggest that among the three anticoagulants tested, heparin can be recommended as the anticoagulant of choice for R. prolixus feeding experiments.

Evaluation of Using Certain Sources of Protien for Feeding Mediterranean Fruit Flies, Ceratitis capitata Adults

Mass rearing cost is one of the important tools for successful implementation the sterile insect technique (SIT) programme. Yeast hydrolyzed (YH) is an effective protein source for feeding the adult flies of C. capitata and widely used in the mass rearing facilities in spite of it is imported product in many countries and very expensive. Three local protein sources, meat bone meal (MBM), plant protein meal (PPM) and soybean protein (SP) were evaluated as adult feed instead of YH. The life span of adult flies, fecundity, fertility and the other reproductive biology were studied to explore the feasibility of these alternative protein sources for maintaining the performance of medfly colony. The results indicated that the fecundity and fertility were drastically reduced in the case of using the three protein sources as compared with the stander one (YH). While, the percentages of adult survival of male and female flies were relatively similar in the different protein sources and it was clearly higher than those fed on only sugar. The results revealed that when the tested protein sources were supplied with YH (1:1), the reproductive biology parameters were improved, the percentages of egg hatch were insignificantly increased to (84.1, 83.5 and 82.4 %) in YH/PPM, YH/MBM and YH/SP treatments, respectively as compared to YH (80.6%). Also, in the same treatments, the egg laid per female per day were higher (24.5, 23.4 and 22.6 eggs/day), respectively than YH tratment (22.2 eggs/day). Moreover, the pupation were significantly reduced and the larval durations were prolonged in PPM, MBM and SP treatments and not affected in YH/PPM, YH/MBM and YH/SP treatments as compared to YH treatment. The results indicated that the three commercial protein sources were effective dietaries when used with the yeast hydrolysate at the ratio 1:1, this procedure will significantly diminished the mass rearing cost of C. capitata.

Semi-field assessment of Spinosad in combination with Altosid briquet and Dudim DT tablets against Aedes aegypti mosquito larvae reared in pond water.

This study aims at evaluating the larvicidal efficacy of slow-release formulations of bacterial insecticide Spinosad blended with two insect growth regulators (IGRs), Altosid XR–briquets and Dudim DT tablets against mosquito larvae of Aedes aegypti. This insect is the cause of dengue arthropod-borne viral disease. Treatment based on vector control using chemicals poses risks to human and environment, while the strategy based on the use of natural products poses lower risks. The results of the present study indicated that the mixture of Spinosad plus Dudim or Altosid tablets continued their fatal activity against the 3rd instar larvae for a longer period than the treatment with Spinosad, Altosid or Dudim tablets alone. The treatment of Spinosad plus either Altosid or Dudim has given effect to female mosquitoes in laying eggs in egg cups containing the treated pond water compared to the control egg cups. The results also showed that the treatment of Spinosad plus Altosid did not affect the egg hatching rate in the treated pond water, while the treatment of Spinosad combination with Dudim showed a significant decrease in the percentage of egg hatching. Use of natural products with larvicidal activities offers better approaches to integrated pest management and insecticide resistance management.

Efficacy of larvicides for the control of dengue, Zika, and chikungunya vectors in an urban cemetery in southern Mexico.

Many countries in Latin America have recently experienced outbreaks of Zika and chikungunya fever, in additional to the usual burden imposed by dengue, all of which are transmitted by Aedes aegypti in this region. To identify potential larvicides, we determined the toxicity of eight modern insecticides to A. aegypti larvae from a colony that originated from field-collected insects in southern Mexico. The most toxic compounds were pyriproxyfen (which prevented adult emergence) and λ-cyhalothrin, followed by spinetoram, imidacloprid, thiamethoxam, and acetamiprid, with chlorantraniliprole and spiromesifen the least toxic products. Field trails performed in an urban cemetery during a chikungunya epidemic revealed that insecticide-treated ovitraps were completely protected from the presence of Aedes larvae and pupae for 6 and 7weeks in spinosad (Natular G30) and λ-cyhalothrin-treated traps in both seasons, respectively, compared to 5-6weeks for temephos granule-treated ovitraps, but was variable for pyriproxyfen-treated ovitraps with and 1 and 5weeks of absolute control in the dry and rainy seasons, respectively. Insecticide treatments influenced the mean numbers of Aedes larvae + pupae in each ovitrap, mean numbers of eggs laid, and percentage of egg hatch over time in both trials. The dominant species was A. aegypti in both seasons, although the invasive vector Aedes albopictus was more prevalent in the rainy season (26.7%) compared to the dry season (10.2%). We conclude that the granular formulation of spinosad (Natular G30) and a suspension concentrate formulation of λ-cyhalothrin proved highly effective against Aedes spp. in both the dry and rainy seasons in the cemetery habitat in this region.