Reduction In Number Of Eggs Research Articles

Effects of Commercial Sunscreens on Survival, Reproduction and Embryonic Development of the Aquatic Snail Biomphalaria glabrata (SAY, 1818).

Over the past few years, there has been a significant increase in the use of sunscreens. Consequently, the occurrence in aquatic environments of ultraviolet filters has also increased. The present study aims to evaluate the toxicity of two commercial sunscreens to the aquatic snail Biomphalaria glabrata. Acute assays were performed with adult snails exposed to solutions of the two products in synthetic soft water. Reproduction and development assays were carried out, involving individual adult and egg masses exposure to assess fertility and embryonic development. Sunscreen A showed a LC50-96h of 6.8g/L and reduction in number of eggs and egg masses per individual in the concentration of 0.3g/L. Sunscreen B presented higher malformation rates in 0.4g/L with 63% of malformed embryos. Results indicate that the formulation used in sunscreens is an important factor in aquatic toxicity and needs to be evaluated before the final product is commercialized.

A critical role for ecdysone response genes in regulating egg production in adult female Rhodnius prolixus.

Ecdysteroids control ovary growth and egg production through a complex gene hierarchy. In the female Rhodnius prolixus, a blood-gorging triatomine and the vector of Chagas disease, we have identified the ecdysone response genes in the ovary using transcriptomic data. We then quantified the expression of the ecdysone response gene transcripts (E75, E74, BR-C, HR3, HR4, and FTZ-F1) in several tissues, including the ovary, following a blood meal. These results confirm the presence of these transcripts in several tissues in R. prolixus and show that the ecdysone response genes in the ovary are mostly upregulated during the first three days post blood meal (PBM). Knockdown of E75, E74, or FTZ-F1 transcripts using RNA interference (RNAi) was used to understand the role of the ecdysone response genes in vitellogenesis and egg production. Knockdown significantly decreases the expression of the transcripts for the ecdysone receptor and Halloween genes in the fat body and the ovaries and reduces the titer of ecdysteroid in the hemolymph. Knockdown of each of these transcription factors typically alters the expression of the other transcription factors. Knockdown also significantly decreases the expression of vitellogenin transcripts, Vg1 and Vg2, in the fat body and ovaries and reduces the number of eggs produced and laid. Some of the laid eggs have an irregular shape and smaller volume, and their hatching rate is decreased. Knockdown also influences the expression of the chorion gene transcripts Rp30 and Rp45. The overall effect of knockdown is a decrease in number of eggs produced and a severe reduction in number of eggs laid and their hatching rate. Clearly, ecdysteroids and ecdysone response genes play a significant role in reproduction in R. prolixus.

Effects of scent leaf (ocimum gratissimum) on intestinal helminths affecting local free range chickens

Scent leaf or Ocimum gratissimum is introduced to test its effectiveness as herbal purgatives in the treatment/eradication of gastrointestinal parasites in native chickens. Therefore, considering the side effects and the extracts and biologically protozoan builds against drugs, more attention should be given to the extracts and biologically active compounds which are isolated from plant species commonly used in herbal medicine. Hence, there is need for the study of potentials use of scent leaf (Ocimum gratissimmum) in the control of gastro-intestinal parasites of local free range chicken. A total of 18 local free range chickens were used for the study. The birds were sourced from the local community market at 17 weeks of age. The local birds were weighed to determine their initial body weight. Six (6) local chickens were allocated to three (3) treatment. The results reveals that all the free range chicken that were given scent leaf extract and commercial dewormer shows great reduction in number of eggs in their feaces. This indicates that scent leaf extract are equally effective as commercial dewormer (mebendazole). From the studies, Ocimum gratissimum is a good antioxidant and also has some medicinal and nutritive values. This method of gastrointestinal helminthes control/eradication is cheap and easy to practice and could be adopted to replace conventional use of anti-helminthic drugs because of recent development of resistance of the helminthes to these drugs. The formulation of the plant extract regimen could be carried out without much technical know-how and the use of highly sophisticated equipment. Consequently, rural dwellers could access this nascent method of eradication of gastrointestinal helminthes in local free range chickens with little training/orientation. From the results of this study it is recommended that Ocimum gratissimum extract and commercial dewormer (Mebendazole) be incorporated into the treatment of local free range chickens without any detrimental effect.

Lavandula dentata L.: Phytochemical Analysis, Antioxidant, Antifungal and Insecticidal Activities of Its Essential Oil.

Antioxidant, antifungal and insecticidal activities of essential oil (EO) extracted from the Moroccan lavender (Lavandula dentata) were investigated and their chemical constituents determined. Gas chromatography with flame ionization detection (GC-FID) and gas chromatography-mass spectrometry analyses (GC-MS) were used to examine the phytochemical composition of EO. Antioxidant potential was examined in vitro by use of three tests: DPPH inhibition, reducing power (FRAP) and total antioxidant capacity (TAC). Antifungal activity was assessed by calculating inhibition of growth of Alternaria alternata, Botrytis cinerea and Fusarium oxysporum. Repellent potential and toxicity of EO by contact and inhalation were performed against Callosobruchus maculatus. Sixteen constituents were detected in the EO of Lavandula dentata. The major component was linalool (45.06%) followed by camphor (15.62%) and borneol (8.28%). EO exhibited a significant antioxidant activity, as measured by DPPH and FRAP assays, with IC50 and EC50 values of 12.95 ± 1.300 mg/mL and 11.88 ± 0.23 mg/mL, respectively. EO of lavender exhibited total antioxidant capacity of 81.28 ± 2.28 mg AAE/g EO. EO of lavender showed an inhibitory effect on mycelial growth against tested fungi and was 100% in the case of B. cinerea. EO caused total mortality of adult C. maculatus from 5 µL/L air with LC50 value of 4.01 µL/L air. Significant reduction in numbers of eggs laid (99.2%) and emergence (100%) was observed in a dose-dependent manner up to maxima of 100% and 99.2%, respectively. EO of lavender also showed a moderate potency to repel insects with a mean of 34.44%. EO of Moroccan Lavandula dentata has potential to be an effective natural agent against free radical damage and could be an environmentally friendly alternative bio-fungicide and bio-insecticide.

Host-delivered RNA interference in tomato for mediating resistance against Meloidogyne incognita and Tomato leaf curl virus

Tomato is a key vegetable crop cultivated in nearly all agricultural regions of the world. It is a protective food very rich in vitamin A and C. Worldwide two major biotic stresses namely root-knot nematode (Meloidogyne incognita) and tomato leaf curl virus (ToLCV) pose a serious threat to its production. Serious environmental concerns associated with the chemical pesticides used for management of these pests compel researchers to look for alternate management strategies. Many recent publications indicate engineering resistance through host delivered RNAi to be an important, sustainable and efficient tool for nematode and virus management. In this study, we have attempted to engineer resistance against M. incognita and ToLCV by stacking dsRNA constructs of the Integrase gene of M. incognita and AC4 genes of ToLCV, using co-transformation protocol in tomato. Transgenic events, so produced, were confirmed at the molecular level by PCR and southern blot. Such T2 events showed absolute absence of leaf curl virus disease symptoms and 62–63% reduction in the number of galls, 51–70% reduction in the number of eggs, 31–38% reduction in number of eggs per egg mass and 66–81% reduction in nematode multiplication factor when compared to the untransformed control plants.The study provides an evidence for generating resistance through RNAi against multiple biotic stresses. This study provides an insight into generating resistance against multiple biotic stresses in tomato through host generated RNA

Field Response of Cowpea, Vigna unguiculata Walper to Four Insecticidal Compounds and Their Residual Toxicity to Callosobruchus maculatus (F.) [Coleoptera: Chrysomelidae] in The Laboratory

There have been paradigm shift to the use of biopesticides as alternative to synthetic pesticides in recent years due to its environment friendliness and non-toxic to the non-target organisms. Therefore, three synthetic insecticides and water extract from neem back powder were evaluated on cowpea in the field and their residual toxicity tested against C. maculatus in the laboratory. The insecticides were applied at the rate of 2ml in 2L of water and 2L of extract from neem back powder on the field. The harvested seeds were infested with C. maculatus to evaluate the residual toxicity of the insecticides. Data on growth and yield parameters were taken on the field while data on adult mortality, oviposition, adult emergence and weight loss were recorded for the laboratory experiment. The results showed positive response of cowpea to the applied chemicals as they had higher values for the number of leaves, branches and reduced number of holes. Number of holes was significant (p< 0.05) at the 8th week with the control having highest number of holes. Cowpea treated with cypermethrin had highest number of pods at both 7th and 8th week and showed significant difference at 7th week. Highest weight of seeds per pod was obtained from the cowpea treated with water extract from neem back powder and was significantly different (p< 0.05) from other treatments. Seeds treated with the three insecticides had the same number of mortality while neem extract had highest but was not significantly different (p> 0.05). There was a reduction in number of eggs laid, adult emergence, seeds with holes and weight loss in the seeds treated with the four insecticide compounds. It was concluded that application of the insecticidal compounds positively enhanced the performance of cowpea on the field and could protect the seeds against C. maculatus in the laboratory. This study revealed that water extract from back powder of neem could be used as a botanical in the protection of cowpea against seed beetles.

Longevity-promoting efficacies of rutin in high fat diet fed Drosophila melanogaster.

Composition of diet significantly impacts lifespan in Drosophila melanogaster. Diet-composition becomes even more crucial while assessing a phytocompound for probable pro-longevity effects in flies. Rutin is a flavonol glycoside present in apple, buckwheat, black tea and green tea. Our previous study had reported hormetic efficacy of rutin to improve longevity and other physiological parameters in Drosophila melanogaster fed with standard diet. This study aimed to understand whether rutin could exhibit similar longevity promoting effects in flies fed with a high fat diet (HFD). In this study, wild type Canton-S males and females were reared on high fat diet (HFD) treated with or without rutin at different doses (100-800 µM) and assessed for survival, food intake, fecundity, locomotion, development, resistance to various forms of stresses and relative mRNA expression of specific genes associated with ageing, namely dFoxO, MnSod, Cat, dTsc1, dTsc2, Thor, dAtg1, dAtg5, dAtg7 and dTor. Rutin at only 400 µM significantly improved survival in males fed with HFD; while at 200 µM and 400 µM it significantly improved survival in females. Doses beyond 400 µM proved detrimental for both sexes. Rutin at 200 µM and 400 µM significantly reduced average food intake in both males and females fed with HFD. A significant reduction in number of eggs laid per female per day was observed in females treated with rutin at 400 µM. Rutin at 200 µM and 400 µM significantly improved climbing efficiency in males and females. A significant reduction in eclosion time was observed in larvae fed with HFD and treated with rutin at 400 µM. Rutin at 400 µM significantly improved resistance of males and females to different stresses namely heat shock, cold shock and starvation stresses. Interestingly, rutin at 400 µM significantly reduced survival of males and females exposed to oxidative stress. In males fed with HFD, rutin at 200 µM showed significantly increased relative expression of dFoxo, MnSod, Cat, dAtg1, dAtg5 and dAtg7; at 400 µM it significantly increased the relative expression of dFoxO, MnSod, Cat, dTsc1, dTsc2, Thor, dAtg1, dAtg5, dAtg7 while decreasing relative expression of dTor. Thus, data from this study collectively showed that rutin at 400 µM and to an extent 200 µM positively impacted lifespan and modulated other physiological parameters in males and females fed with HFD.

Characteristics and function of cathepsin L3 from Schistosoma japonicum.

Schistosomiasis is still prevalent and seriously endangering the health of people and livestock in many countries. There have been great efforts to develop vaccines against schistosomiasis for prolonged protection in epidemic areas. Molecules from lung-stage schistosomula have been regarded as potential vaccine candidates against schistosomiasis. Our previous work has shown that cathepsin L3 from Schistosoma japonicum (SjCL3) is expressed in lung-stage schistosomula, but its role is not well known. In the present study, we characterized SjCL3 and detected its effect as a possible vaccine in vivo and in vitro. From the results of quantitative PCR (qPCR) and western blot, SjCL3 was present throughout the lifecycle of the worm, and its relative expressed level was higher in the liver eggs and adult worms than other stages. Additionally, immunofluorescence assay showed that SjCL3 was mainly concentrated in the eggshell, alimentary canal, and musculature of worms. Compared with the adjuvant group, the immunization of SjCL3 in mice resulted in a 28.9% decrease in worm burden and a 29.2% reduction in egg number in the host liver. In antibody-dependent cell-mediated cytotoxicity (ADCC) insecticidal experiments in vitro, the existence of SjCL3 could in part suppress adherence between macrophages and worm. The above results indicated that the immunization of SjCL3 could induce limited immune protection against S. japonicum infection in mice, and this protease played a role in breaking the process of ADCC, which was beneficial to the survival of worms.

Co-exposure to ketoconazole alters effects of bisphenol A in Danio rerio and H295R cells

Chemicals are present in combination in ambient water, however toxicities of their mixtures are not well understood. This study investigated the effects of ketoconazole (KCZ) on the responses induced by bisphenol A (BPA) in zebrafish and in human adrenocarcinoma (H295R) cells. After exposure to BPA alone or mixed with KCZ for 21 d, egg production, relative tissue weights, sex hormone levels, cytochrome P450 (CYP)3a activity, and transcriptions of genes related to CYP metabolism, vitellogenesis, and steroidogenesis were determined in zebrafish. Male fish were more sensitive to the adverse effects of BPA than females, and the presence of KCZ potentiated the BPA-induced estrogenic responses in the male and anti-estrogenic responses in the female fish. In male zebrafish exposed to BPA, a significant reduction in egg number and relative gonad weight, an increase in 17β-estradiol (E2) to testosterone (T) ratio, and an upregulation of vtg, erα, and cyp19a genes were observed. Under KCZ, BPA exposure resulted in a significant downregulation of cyp3a65 and pxr genes and an increase in estrogenic responses in males. In female fish, anti-estrogenic effects, such as a decrease in E2 concentration, were observed following the combined exposure. These results indicate that KCZ could increase the toxicity of the chemicals that depend on the given CYP metabolism for their elimination or other crucial functions such as steroidogenesis. Co-exposure to BPA and KCZ in H295R cells also increased E2 and decreased T production. Release and presence of this azole compound warrant caution, because it could modify adverse effects of BPA.

Effects of Short-term Climate Variation on a Long-lived Frog

We assessed the effects of short-term, naturally oscillating, climate variation on Crawfish Frogs (Lithobates areolatus), a long-lived member of the family Ranidae. Our data demonstrate 1) no relationship between drought conditions (high temperatures, low precipitation) and either breeding onset (phenological shifts) or breeding peaks; 2) no relationship between drought and adult survivorship (although there were trends; both females and males experienced their lowest survivorship estimates during the wettest years, a contrary finding related to crayfish burrow occupancy); 3) a strong relationship between drought and breeding duration; 4) a strong, inverse correlation between drought and body condition in both females and males; and as a result, 5) a relationship between drought and fecundity with potentially serious demographic consequences. If we assume that the mass of an individual egg remains constant under various climate conditions—i.e., that a reduction in egg mass equals a reduction in egg number...

Developmental Dynamics of Globodera ellingtonae in Field-Grown Potato.

Globodera ellingtonae is a recently described nematode parasite of potato, which is closely related to the economically significant potato cyst nematodes G. rostochiensis and G. pallida. Because of the close relationship of G. ellingtonae to the potato cyst nematodes, a greater understanding of its biology is critical. Two experiments were conducted in Oregon to explore the developmental biology of G. ellingtonae in field-grown potato. The first experiment was conducted in 2013 and 2014 to determine the developmental timing of G. ellingtonae life stages and reproduction by inoculating potato with soil containing cysts followed by weekly collection of soil and root samples. Life stages; second-stage juveniles (J2) in soil and roots, third-stage juveniles (J3) and fourth-stage (J4) females and males in roots, males and females or cysts in soil, and egg number and developmental state were quantified. Normalizing across years using accumulated developmental degree days above 6°C (DD6), J2 of G. ellingtonae were found in soil from 41 to 588 DD6; two peaks of J2 invasion of roots were observed. The first adult females were observed at 387 and 449 DD6 in 2013 and 2014, respectively. The next generation of eggs was first observed from 675 to 854 DD6 and 50% egg development (containing a vermiform juvenile) occurred at approximately 920 DD6. A second J2 hatch was observed in both years at 927 to 1,073 DD6. The developmental dynamics of G. ellingtonae observed here are similar to those reported for G. rostochiensis and G. pallida from several geographical locations. In the second experiment, the effect of potato and bare soil on G. ellingtonae egg hatch was evaluated; in 2014 and 2015, packages containing cysts in soil were buried under potato or in bare soil at the time of planting and eggs per cyst determined weekly. Across years, a significant reduction in eggs per cysts under potato (>50%) was observed 35 days after planting (DAP) and, at 63 DAP, eggs per cyst were reduced by 76 to 96% compared with initial egg per cyst densities. In bare soil, the maximum reduction in densities of eggs per cyst was 55 to 73%. This annual reduction in egg numbers of G. ellingtonae in bare soil is similar to that reported for G. pallida and G. rostochiensis.

Effect of cultural practices on potato cyst nematode population dynamics and potato tuber yield

Health concerns related to the use of pesticides are increasing the interest in alternate use of pest and disease control strategies. Accordingly, different cultural practices, viz., trap cropping, soil solarization and nonsolanaceous crops were evaluated for the management of potato cyst nematode during summer 2013–14 and 2014–15. Among the potato cultivars used as trap crop, Kufri Jyoti attracted more PCN juveniles and recorded maximum reduction in cyst population than Kufri Swarna. In the succeeding crop Kufri Girdhari, wherein Kufri Jyoti used as trap crop recorded more yield than Kufri Swarna in both the spacings. In the soil solarisation experiment, minimum PCN reproduction factor (Rf) was recorded in soil solarisation followed by application of neem cake (@ 5 t/ha) in combination with Trichoderma viride (@ 5 kg/ha). The same treatment also produced significantly maximum yield during 2013–14 however, during 2014–15 the yield was found to be on par with soil solarisation + carbofuran (2 kg a.i./ha). All the non-solanaceous crops tested reduced the PCN multiplication ratio. Among different non-solanaceous crops, radish recorded 19.6–21.0% reduction in number of cysts and 12.2–16.2% reduction in number of eggs per cyst. Which was followed by garlic, it recorded 15.9–17.7% and 10.3–11.6% reduction in number of cysts and eggs respectively, during 2013–14 and 2014–15. Therefore, the above said treatments either alone or in combination can be used to manage the PCN.

Coadministration of nematophagous fungi for biological control over gastrointestinal helminths in sheep in the semiarid region of northeastern Brazil

This study aimed to evaluate coadministration of Duddingtonia flagrans and Monacrosporium thaumasium in a sodium alginate matrix for controlling gastrointestinal helminths in young and adult sheep in the semiarid region of northeastern Brazil. An area of 1ha was divided into two paddocks, in which two experimental groups (fungus and control) were formed, each consisting of six adult females and ten young males. In each group, two subgroups were formed in accordance with the animal category (adult or young). In the fungus group, each animal received 3g of pellets containing 0.6g of fungal mycelium, with 0.3g of D. flagrans and 0.3g of M. thaumasium for each 10kg of body weight, in their feed twice a week, for six months. In the control group, each animal received 3g of pellets without fungus for each 10kg of body weight, in their feed twice a week, for six months, serving as a witness group. Reductions in numbers of eggs per gram of feces of 76% among the adult sheep in the fungus group and 83% among the young sheep in the fungus group were observed, in comparison with their respective control subgroups. The groups that received these fungi needed less salvage deworming and presented better packed cell volume percentages, better weight gain and lower levels of L3/kg dry matter in their paddock than the control groups. Thus, it was concluded that coadministration of D. flagrans and M. thaumasium was effective in controlling gastrointestinal helminths of adults and young sheep in the semiarid region of northeastern Brazil.

Fumigant Toxicity of camphor Against Tetranychas urticae Koch and Two Phytoseid Predators (Tetranychidae: phytoseiidae)

In attempt to find a new fumigant acaricide could be used in green houses fumigant toxicity of camphor was studied against Tetranychus urticae Koch and two predators i.e. Neoseiulus californicus (Mc.Gr.) and Phytoseiulus persimilis A.-H. Camphor vapor gave a reasonable toxicity. Increasing temperature resulted in increasing toxicity as raise of temperature from 20 to 35°C decreased LC50 values from 3.28 to 2.61 mg/L and from 7.13 to 2.76 mg/L in case values 3.48 and 3.97 mg/L under 25°C, respectively. Subjecting protonymphs to LC50 for 24h resulted in significant shortage in the oviposition period and reduction in egg number reflecting reduction in finite rate of increase from 1.349 (non-treated mites) to 1.239 female/ female/day.

Efficacy of indoxacarb applied to cats against the adult cat flea, Ctenocephalides felis, flea eggs and adult flea emergence

BackgroundA study was conducted to evaluate the effect of indoxacarb applied to cats on adult cat fleas, Ctenocephalides felis, flea egg production and adult flea emergence.MethodsSixteen cats were selected for the study and allocated to two treatment groups. Eight cats were treated with a 19.5% w/v topical spot-on solution of indoxacarb on day 0 and eight cats served as untreated controls. Each cat was infested with 50 fleas on Days -2, 7, 14, 21, 28, 35 and 42. On Days 1, 2, and 3, and at 2 and 3 days after each post treatment reinfestation flea eggs were collected from the pan under each cat cage. Eggs were counted and viability assessed by evaluating adult flea emergence 28 days after egg collection. Three days after treatment or infestation, each cat was combed to remove and count live fleas.ResultsTreatment with indoxacarb provided 100% efficacy following infestations on day -2, 7, 14, 21 and 28 and efficacy was 99.6% following infestations on days 35 and 42. Egg production from indoxacarb treated cats was reduced by 99.9% within 72 hours of treatment. For subsequent infestations no eggs were produced from treated cats from day 8 through day 30. Egg production was still reduced by ≥95.8% through day 45. Indoxacarb treatment also reduced adult flea emergence from eggs for 5 weeks after treatment. The combination of reduction in egg numbers and egg viability from indoxacarb treated cats reduced predicted flea emergence by 100% from days 2 – 31 and 99.9%, 100%, 96.4% and 99.0% on days 37, 38, 44 and 45, respectively.ConclusionsA topical spot-on formulation of indoxacarb provided ≥99.6% efficacy against flea infestations on cats for 6 weeks following a single treatment. Indoxacarb also eliminated or markedly reduced egg production for the entire evaluation period and reduced the viability of the few eggs that were produced from Day 1 through Day 38. Given indoxacarb’s effect on adult fleas, egg production and egg viability; this formulation can interrupt flea reproduction on treated cats for at least 6 weeks after treatment.

Effects of Chlorantraniliprole and Thiamethoxam Rice Seed Treatments on Egg Numbers and First Instar Survival of <I>Lissorhoptrus oryzophilus</I> (Coleoptera: Curculionidae)

Effects of treatment of rice seeds with an anthranilic diamide, chlorantraniliprole, and a neonicotinoid, thiamethoxam, on egg laying and first instar survival in rice water weevil, Lissorhoptrus oryzophilus Kuschel, were examined under greenhouse conditions. Exposure of adult weevils to rice (6-7 leaf stage) grown from seeds treated with chlorantraniliprole and thiamethoxam resulted in reduction in numbers of eggs and first instars. The low egg numbers by adults exposed to chlorantraniliprole-treated plants was confirmed as a sublethal effect on adults: adult survival was not impacted after 4 d of feeding on foliage from chlorantraniliprole-treated plants but the number of eggs laid by these weevils was reduced when released on untreated plants. Furthermore, a comparison of first instar emergence from chlorantraniliprole-treated plants and from untreated plants infested with weevils previously exposed to this chemical suggested that chlorantraniliprole was also reducing egg or first instar survival. In contrast, adults that fed on foliage from thiamethoxam-treated plants showed increased mortality. Possible sublethal effects of thiamethoxam on the number of eggs laid by adults were investigated by infesting untreated plants with weevils that survived exposure to thiamethoxam via foliar feeding (7 microg active ingredient/seed). Prior exposure to thiamethoxam through adult feeding reduced egg numbers. However, potential larvicidal or ovicidal effects of thiamethoxam seed treatments could not be detected in this study because of low first instar emergence from both thiamethoxam-treated plants and from untreated plants infested with weevils previously exposed to this chemical. These experiments revealed that the two seed treatments accomplish weevil control in different ways.

Maternal care in the Neotropical harvestman Liogonyleptoides tetracanthus (Opiliones: Gonyleptidae)

We describe post-ovipositional maternal care in Liogonyleptoides tetracanthus Mello-Leitão 1932 (Gonyleptinae) and experimentally evaluate the protective role of this behavior against egg predation under laboratory conditions. Females laid 138.8 eggs on average and remained close to the clutch during the entire day. Eggs hatched after 11–15 days and nymphs dispersed from maternal protection after one to two days. Most of the experimental clutches left unattended were entirely consumed by conspecifics in 2–3 days. There was no reduction in egg number in the clutches protected by females. Although biological data are scarce, there are cases of egg hiding, paternal and maternal care within the subfamily Gonyleptinae. This diversity of forms of parental care is unusual when compared to other gonyleptid subfamilies, and future systematic revisions of the polyphyletic Gonyleptinae should include parental care as a potential source of phylogenetic information.

Estimation of genetic parameters for body weight and egg production traits in Mazandaran native chicken

Native chicken breeding station of Mazandaran was established in 1988 with two main objectives: genetic improvement through selection programs and dissemination of indigenous Mazandarani birds. (Co)variance components and genetic parameters for economically important traits were estimated using (bi) univariate animal models with ASREML procedure in Mazandarani native chicken. The data were from 18 generations of selection (1988-2009). Heritability estimates for body weight at different ages [at hatch (bw1), 8 (bw8), 12 (bw12) weeks of ages and sex maturation (wsm)] ranged from 0.24 ± 0.00 to 0.47 ± 0.01. Heritability for reproductive traits including age at sex maturation (asm); egg number (en); weight of first egg (ew1); average egg weight at 28 (ew28), 30 (ew30), and 32 (ew32) weeks of age; their averages (av); average egg weight for the first 12 weeks of production (ew12); egg mass (em); and egg intensity (eint) varied from 0.16 ± 0.01 to 0.43 ± 0.01. Generally, the magnitudes of heritability for the investigated traits were moderate. However, egg production traits showed smaller heritability compared with growth traits. Genetic correlations among egg weight at different ages were mostly higher than 0.8. On the one hand, body weight at different ages showed positive and relatively moderate genetic correlations with egg weight traits (ew1, ew28, ew30, ew32, ew12, and av) and varied from 0.30 ± 0.03 to 0.59 ± 0.02. On the other hand, low negative genetic correlations were obtained between body weight traits (bw1, bw8, bw12, and wsm) and egg number (en). Also, there is low negative genetic correlation (-24 ± 0.04 to -29 ± 0.05) between egg number and egg weight. Therefore, during simultaneous selection process for both growth and egg production traits, probable reduction in egg production due to low reduction in egg number may be compensated by increases in egg weight.

Evaluation of leaf and vine powders of Secamone afzelii (Schult) K. Schum for control of Callosobruchus maculatus (Fab.) (Coleoptera: Bruchidae) in stored cowpea Vigna unguiculata (L.) Walp.

The experiment was carried out to evaluate the efficacy of Secamone afzeliileaf and vine powders applied at the rate of 0.5g, 1.0g, 1.5g and 2.0g underambient laboratory conditions on Callosobruchus maculatus on stored cowpea.Mortality of adult insects at 48 h post treatment, number of eggs laid,adult emergence, adult exit holes and percentage weight loss in each treatmentwere compared with those of control. The results indicated that vinepowder caused significantly greater kill (P < 0.05) of C. maculatus adultswhen applied at 2.0g than other dosages. The application rate of 2.0g of leafpowder was able to cause reduction in number of eggs laid by the weevil(5.67/20g seed) and significantly (P < 0.05) suppressed adult emergence(21.12). Adult exit holes and percentage weight loss were significantly reducedat all levels of application. It is concluded that Secamone afzelii hasgreat potential for use as a plant‐based biopesticide for controlling C. maculatuson stored cowpea.

Repellency and toxicity of extract from Francoeria crispa (Forsk.) to Eutetranychus orientalis (Klein) (Acari: Tetranychidae)

Laboratory bioassays were conducted to characterise the activity of the extract Francoeria crispa (Forsk.) (Family: Compositae) against the citrus brown mite, Eutetranychus orientalis (Klein). Ethyl acetate was tested for preparing the crude extract of F. crispa. The extract was tested for its toxicity against eggs and adult females of the pest E. orientalis. Ethyl acetate extract of F. crispa affected the behaviour, toxicity and fecundity of females under laboratory conditions. The extract had similar toxic effects on egg stage and adult females of E. orientalis (LC50 = 0.00050 g/ml), respectively. Leaf discs treated with increasing concentrations of ethyl acetate extract of F. crispa showed a high percentage of repellency (97.45%), respectively. Treated females with LC50 concentration of ethyl acetate extract showed a higher remarkable percentage of mortality as well as a reduction in the total number of eggs laid during 7 days. Ten isolated fractions of ethyl acetate crude extract from F. crispa were detected. The results clearly indicate that the isolate number (10) was the most toxic isolate on eggs and females of E. orientalis (LC50 = 0.00014 and 0.000125 g/ml), respectively.