Oviposition Deterrent Activity of Some Wild Plants for Adult Females of Chrysomya albiceps with Medical and Veterinary Importance.

<b>Background and Objective:</b> <i>Chrysomya albiceps</i> is widely spread worldwide, causing myiasis in both humans and animals and playing a mechanical role in the spreading of helminths, viruses and bacteria. Searching for new and safe alternative control methods is very important to eliminate the transmission of pathogens. This study aims to determine the oviposition-deterrent activity of <i>Juniperus procera</i>, <i>Artemisia absinthium</i>, <i>Rosmarinus officinalis</i> and <i>Hypoestes forskaolii</i> wild plants against adult <i>Chrysomya albiceps</i>. <b>Materials and Methods:</b> The effect of plant extracts from <i>Juniperus procera</i>, <i>Artemisia absinthium</i>, <i>Rosmarinus officinalis</i> and <i>Hypoestes forskaolii</i> plants were tested against adult females of <i>Chrysomya albiceps</i> for oviposition deterrent or repellency. These extracts resulted in oviposition deterrent efficacy for adult females of <i>C. albiceps</i> based on the plant type, plant part (leaves or stems), extract type (methanol, acetone and petroleum ether) and tested dose. <b>Results:</b> The highest anti-oviposition activity against <i>C. albiceps</i> females presented from <i>A. absinthium</i> stems acetone extract at a dose of 1 mg cm² by 100 %, while at 0.5 mg cm² recorded remarkable repellency by 86.7% as compared with the control treatment. According to the dose-response relationship, <i>A. absinthium</i> methanol and acetone extracts were ED₅₀ values of 0.85, 0.319 mg cm² (leaves) and 1.88, 0.576 mg cm² (stems), followed by <i>J. procera</i> methanol extract by 0.983 mg cm² (leaves) and 0.98 mg cm² (stems), respectively achieved highest oviposition deterrent efficiency as compared with other extracts. <b>Conclusion:</b> The high repellency activities of these extracts can be utilized to stop <i>C. albiceps</i> flies from laying eggs on wounds and transmitting myiasis diseases to humans and animals and could potentially replace pesticides used in the future control programs of flies.

Circadian regulation of calcium and phosphorus homeostasis during the oviposition cycle in laying hens.

Maintenance of calcium and phosphorus homeostasis in laying hens is crucial for preservation of skeletal integrity and eggshell quality, though physiological regulation of these systems is incompletely defined. To investigate changes in mineral and vitamin D3 homeostasis during the 24-h egg formation cycle, 32-wk-old commercial laying hens were sampled at 1, 3, 4, 6, 7, 8, 12, 15, 18, 21, 23, and 24 h post-oviposition (HPOP; n ≥ 4). Ovum location and egg calcification stage were recorded, and blood chemistry, plasma vitamin D3 metabolites, circulating parathyroid hormone (PTH), and expression of genes mediating uptake and utilization of calcium and phosphorus were evaluated. Elevated levels of renal 25-hydroxylase from 12 to 23 HPOP suggest this tissue might play a role in vitamin D3 25-hydroxylation during eggshell calcification. In shell gland, retinoid-x-receptor gamma upregulation between 6 and 8 HPOP followed by subsequently increased vitamin D receptor indicate that vitamin D3 signaling is important for eggshell calcification. Increased expression of PTH, calcitonin, and fibroblast growth factor 23 (FGF23) receptors in the shell gland between 18 and 24 HPOP suggest elevated sensitivity to these hormones toward the end of eggshell calcification. Shell gland sodium-calcium exchanger 1 was upregulated between 4 and 7 HPOP and plasma membrane calcium ATPase 1 increased throughout eggshell calcification, suggesting the primary calcium transporter may differ according to eggshell calcification stage. Expression in shell gland further indicated that bicarbonate synthesis precedes transport, where genes peaked at 6 to 7 and 12 to 18 HPOP, respectively. Inorganic phosphorus transporter 1 (PiT-1) expression peaked in kidney between 12 and 15 HPOP, likely to excrete excess circulating phosphorus, and in shell gland between 18 and 21 HPOP. Upregulation of FGF23 receptors and PiT-1 during late eggshell calcification suggest shell gland phosphorus uptake is important at this time. Together, these findings identified potentially novel hormonal pathways involved in calcium and phosphorus homeostasis along with associated circadian patterns in gene expression that can be used to devise strategies aimed at improving eggshell and skeletal strength in laying hens.

Effects of Dietary Supplementation of Arginine-Silicate- Inositol and Phytase Complex on Performance and Blood Biochemical Traits of Laying Hens.

Arginine silicate inositol complex (ASI; Arg = 49.47%, silicone = 8.2%, inositol = 25%) is a novel, bioavailable source of Si and Arg and may offer potential benefits for laying hens' performance. The aim of this study was to evaluate the effect of Arginine-Silicate and inositol/phytase on the performance of laying hens. A total of 90 laying hens, 25 weeks old, were randomly assigned to 6 treatments with 3 replicates (5 birds per replicate). The treatments were as follows: 1ST treatment PC: positive Control group (basal diet without additives (, 2nd treatment: basal diet +1000 mg/kg arginine-silicate complex (49.5±8.2 % respectively), 3d treatment: basal diet +1000 mg/kg arginine-silicate- inositol (ASI) complex (49.5, 8.2 , 25 % respectively) , 4th treatment: T 2 +500 FTU/kg , 5th treatment: T2 +1000 FTU/kg and 6th treatment: T2+2000 FTU/kg . Results indicate a significant increase (P<0.05) in hen house production (H.H. pro.%) of T5 (95.06 %)compared with T1(91.67%) and no significant differences between T2, T3, T4, T6 (91.84, 93.21, 93.46, 92.98%) and compared with T1 and T5. were no significant difference observed in average egg weight and egg mass between the experimental treatments all over the period. Daily feed intake (DFI) significantly decreased (P<0.05) with supplementing diets with deferent levels of phytase with arginine-silicate mixture T4, T5, andT6 (113.56،113.06، 112.10 g) compared with T1 (114.34 g ) which has no significant differences compared with T2 and T3 (113.96, 113.92 g). Phytase supplementation significantly (P<0.05) improved FCR g feed/egg in T5 (119.02) compared with T1 and T2 (124.89, 124.32), while no significant differences between T3.T4.T6 treatments (122.39, 121.80, 120.69) respectively and compared with other treatments. The experimental treatments observed no significant difference in g feed/ g egg.

Dietary exogenous phytase improve egg quality, reproductive hormones, and prolongs the lifetime of the aging Hy-Line brown laying hens fed nonphytate phosphorus.

The study examined how adding phytase to nonphytate phosphorus (NPP) diets affected performance, egg quality, reproductive hormones, and plasma biochemical indices in 73- to 80-wk-old laying hens. Six treatments with 5 replicates of 18 Hy-Line brown laying hens each were randomly assigned. Three isonitrogenous, isocaloric diets containing consistent calcium levels (3.8%) were formulated to contain 0.20, 0.25, and 0.30% NPP, treated with or without phytase supplementation (1,000 FYT per kg feed, Ronozyme HiPhos-L, Aspergillus oryzae 6-phytase). The results showed that the addition of phytase to the diet containing 0.20, 0.25, and 0.30% NPP increased egg production by 1.50, 1.64, and 0.97%, respectively, and improved eggshell thickness. Also, use of phytase in the diet contain 0.25, and 0.30% NPP increased the plasma concentration of albumin (ALB), high-density lipoprotein (HDL), phosphorus (P), and plasma follicle-stimulating hormone (FSH), plasma calcium (Ca), estradiol-17ß (E2ß), and luteinizing hormone (LH). In contrast, the egg weight, feed intake, egg mass, feed conversion ratio, albumen height, Haugh unit, yolk, and shell color were unaffected. It can be advisable to use phytase supplementation in an elderly laying hen's diet contain 0.25, and 0.30% NPP to improve shell quality and positively impact reproductive hormones leading to the persistence of egg production.

Monoterpene alcohols induced by sweet potato weevil larvae deter conspecific adults from feeding and oviposition.

BACKGROUND: Intraspecific competition is shared in the insect world, especially under the condition of limited food and space resources. To avoid intraspecific competition and increase offspring survival, insects have evolved various effective strategies. A widely-accepted tactic is employing chemical cues, which are frequently utilized as indicators of conspecific colonization. The sweet potato weevil (SPW), Cylas formicarius, is a destructive pest of sweet potatoes. Its larvae bore into sweet potatoes and alter the emission of odors. The present study aimed to investigate whether volatiles associated with SPW larvae feeding influence the behavioral preference of conspecific adults. RESULTS: Volatiles from SPW larvae-infested sweet potatoes were collected by a head-space method and analyzed using gas chromatography-electroantennogram detector (GC-EAD) and gas chromatography-mass spectrometry (GC-MS). Five compounds eliciting EAD responses from the antennae of both male and female adult SPW were identified from sweet potatoes with the third-instar larvae, including linalool, citronellol, nerol, geraniol, and ipomeamarone. Four monoterpene alcohols significantly repelled SPW adults from feeding and oviposition at higher doses in the behavioral preference bioassays. Among them, geraniol displayed the strongest repellent activities for SPW feeding and oviposition. These results suggested that SPW larvae could reduce colonization of adult SPWs by inducing monoterpene alcohols, thereby avoiding intraspecific competition. CONCLUSION: The present study demonstrated that volatile monoterpene alcohols induced by SPW larvae are chemical cues of larvae occupation for SPW adults to change their behavioral preference. Unveiling factors that mediate avoidance of intraspecific competition could help develop repellents or oviposition deterrents for SPW control. © 2023 Society of Chemical Industry.

Differential effects of continuous and intermittent daytime food deprivation periods on metabolism and reproductive performance in diurnal zebra finches.

We investigated whether food availability effects on metabolism and reproduction are the result of the sum effect of daily feeding (food availability) and starvation (food deprivation) periods. Adult zebra finches were paired and subjected to a time-restricted feeding (TRF) regimen consisting of continuous and intermittent daytime food deprivation periods. Birds were given food during the 12-h day for a total of 4-h in the evening (1 *4-h, hour 8-12), or in 2 splits of 2 h each (2 * 2-h) or 4 splits 1 h each (4 * 1-h), with controls on food ad libitum, until they had the first egg clutch. TRF caused significant changes in hepatic expression of metabolism-associated sirt1, egr1, pparα and foxo1 genes despite no difference in the food intake, body mass and blood glucose levels. Importantly, TRF resulted in a significant reduction in plasma testosterone and estradiol levels, delayed nest-building and egg laying, and reduced clutch size. Concurrently, under TRF regimes, we found a significantly lower expression of th and mtr genes linked with motivation and affiliation (but not of dio2, dio3, gnrh1 and gnih genes linked with gonadal maturation) in the hypothalamus, and of star and hook 1 genes in the testes and star, cyp19 and erα genes in the ovary. These results demonstrate the importance of daily food deprivation times on the metabolism and reproduction, and suggest a possible provisioning of energy available from daily feeding for the maintenance of body condition at the expense of reproduction performance in diurnal animals.

Volatiles as Attractants of Mahogany Shoot Borer, Hypsipyla grandella Zeller (Lepidoptera: Pyralidae).

The mahogany shoot borer, Hypsipyla grandella Zeller (Lepidoptera: Pyralidae), is one of the most economically important pests in all American tropical forests because it prevents the establishment of monoculture plantations of the family Meliaceae, such as Spanish cedar, Cedrela odorata L. Various studies have focussed on the bioecological aspects and the chemical and silvicultural control of this pest. However, relatively little is known about the biological interactions between this insect and its host plant. In this study, the shoot borer's behavior and attraction response to cedar host plants was evaluated in field cages. We also identified the volatiles emitted by healthy C. odorata plants that were attractive to H. grandella adults. The attraction to headspace volatiles from cedar plants and a synthetic blend were evaluated in a Y-glass tube olfactometer. We observed that virgin and mated females exhibited low activity at night, frequent movement of the antennae, sporadic flight activity, and short (< 10 s) and long (> 30 s) wing-fanning. Virgin females assumed a calling position, whereas mated females exhibited three periods of oviposition. The results showed that all evaluated categories - virgin females, virgin males, and mated females - were attracted to cedar plants. We identified the following volatile compounds: α-pinene, (E)-ß-ocimene, 2-ethyl-1-hexanol, limonene, nonanal, (E)-4,8-dimethyl-1,3,7-nonatriene, α-copaene, ß-caryophyllene, and germacrene D. A synthetic blend significantly attracted virgin male and mated female shoot borers. Our results suggested that C. odorata volatiles compounds are responsible for the attraction of H. grandella.

Polyhydroxy Acids as Fabaceous Plant Components Induce Oviposition of the Common Grass Yellow Butterfly, Eurema Mandarina.

The common grass yellow butterfly, Eurema mandarina is a Fabaceae-feeding species, the females of which readily oviposit on Albizia julibrissin and Lespedeza cuneata in mainland Japan. We previously demonstrated that the methanolic leaf extracts of these plants, and their highly polar aqueous fractions strongly elicit female oviposition. Furthermore, the three subfractions obtained by ion-exchange chromatographic separation of the aqueous fraction have been found to be less effective alone, but synergistically stimulate female oviposition when combined. This indicates that female butterflies respond to multiple compounds with different acidity. We have previously identified d-pinitol from the neutral/amphoteric subfractions and glycine betaine from the basic subfractions as oviposition stimulants of E. mandarina. The present study aimed to identify active compounds in the remaining acidic subfractions of A. julibrissin and L. cuneata leaf extracts. GC-MS analyses of trimethylsilyl-derivatized samples revealed the presence of six compounds in the acidic subfractions. In bioassays using these authentic chemicals, erythronic acid (EA) and threonic acid (TA) were moderately active in eliciting oviposition responses in E. mandarina, with their d-isomers showing slightly higher activity than their l-isomers. Female responsiveness differed between d-EA and l-TA, the major isomers of these compounds in plants, with the response to d-EA reaching a plateau at concentrations above 0.005% and that to l-TA peaking at a concentration of 0.01%. The natural concentrations of d-EA and l-TA in fresh A. julibrissin and L. cuneata leaves were sufficient to stimulate oviposition. Furthermore, mixing 0.001% d-EA or 0.001% l-TA, to which females are mostly unresponsive, with 0.1% d-pinitol resulted in a synergistic enhancement of the oviposition response. These findings demonstrate that E. mandarina females utilize both polyhydroxy acids, EA and TA, as chemical cues for oviposition.

1-Octanol emitted by Oecophylla smaragdina weaver ants repels and deters oviposition in Queensland fruit fly.

Humans have used weaver ants, Oecophylla smaragdina, as biological control agents to control insect pests in orchards for many centuries. Over recent decades, the effectiveness of weaver ants as biological control agents has been attributed in part to deterrent and oviposition inhibiting effects of kairomones produced by the ants, but the chemical identity of these kairomones has remained unknown. We have identified the kairomone responsible for deterrence and oviposition inhibition by O. smaragdina, providing a significant advance in understanding the chemical basis of their predator/prey interactions. Olfactometer assays with extracts from weaver ants demonstrated headspace volatiles to be highly repellent to Queensland fruit fly, Bactrocera tryoni. Using electrophysiology and bioassays, we demonstrate that this repellence is induced by a single compound, 1-octanol. Of 16 compounds identified in O. smaragdina headspace, only 1-octanol evoked an electrophysiological response from B. tryoni antennae. Flies had greatly reduced oviposition and spent significantly less time in an olfactometer arm in the presence of 1-octanol or a synthetic blend of headspace volatiles containing 1-octanol than in the presence of a synthetic blend of headspace volatiles without 1-octanol, or clean air. Taken together, our results demonstrate that 1-octanol is the functional kairomone component of O. smaragdina headspace that explains repellence and oviposition deterrence, and is hence an important contributor to the effectiveness of these ants as biological control agents.

Modeling and validation of oviposition by a polyphagous insect pest as a function of temperature and host plant species.

Modeling oviposition as a function of female insect age, temperature, and host plant suitability may provide valuable insight into insect population growth of polyphagous insect pests at a landscape level. In this study, we quantified oviposition by beet leafhoppers, Circulifer (= Neoaliturus) tenellus (Baker) (Hemiptera: Cicadellidae), on four common non-agricultural host plant species [Erodium cicutarium (L.) L'Hér. (Geraniaceae), Kochia scoparia (L.) Schrader (Amaranthaceae), Plantago ovata Forsskál (Plantaginaceae), and Salsola tragus L. (Amaranthaceae)] at two constant temperature conditions. Additionally, temperature-based oviposition models for each host plant species were validated, under semi-field and greenhouse conditions. We found that K. scoparia was the most suitable host plant, and optimal temperature for oviposition was estimated to be 30.6°C. Accordingly, beet leafhoppers appear to be well-adapted to high-temperature conditions, so increasing temperatures due to climate change may favor population growth in non-agricultural areas. Maximum total fecundity (Rm) was used as an indicator of relative suitability of host plants. S. tragus has been considered an important non-agricultural host plant, however, we found that S. tragus and E. cicutarium have lower Rm compared to K. scoparia and P. ovata. The combination of detailed experimental oviposition bioassays, modeling, and model validation is considered widely relevant and applicable to host plant assessments and modeling of population dynamics of other polyphagous insect pests.

The Relative Preference of Empoasca onukii (Hemiptera: Cicadellidae) for Oviposition on Twenty-Four Tea Cultivars.

The tea green leafhopper, Empoasca onukii Matsuda (Hemiptera: Cicadellidae) is currently one of the most threatening pests of tea production in China. Several approaches have been used to identify the resistance of different tea cultivars to this important tea pest. However, relatively limited information has been documented about its oviposition preferences. This study aimed to elucidate the preferential oviposition of E. onukii among 24 tea cultivars. Towards this objective, a multi-selective test for E. onukii oviposition was conducted in the laboratory, and the egg densities of E. onukii on 24 varieties were also surveyed in plantations at different time periods during the tea plant growing season in 2019. There was a significant difference in E. onukii egg densities among the 24 cultivars studied in both laboratory tests and the field investigations. Moreover, there was a positive correlation between the laboratory and field data for the number of eggs laid per cultivar. According to the laboratory and field evaluations, 2 cultivars were identified as very-susceptible for E. onukii oviposition, while another 5 cultivars were assigned as susceptible, 9 cultivars were classified as resistant and 2 cultivars were identified as very-resistant, respectively. This information on the oviposition preference for E. onukii on different cultivars could be used as a selection parameter for further breeding of leafhopper-resistant tea cultivars.

Bottom-up effects of drought on the growth and development of potato, Leptinotarsa decemlineata Say and Arma chinensis Fallou.

BACKGROUND: Global climate change will result in increasingly arid weather that will have a significant impact on agriculture. The occurrence dynamics of plants, phytophagous insects and their natural enemies under drought conditions have attracted much attention. The consequences could be useful for controlling insect herbivores. Leptinotarsa decemlineata (Say) is one of the most important pests of potato, and causes serious damage to potato production. Arma chinensis (Fallou) is a parasitoid of L. decemlineata. However, how drought will affect tritrophic interactions between potato and these insects remains unknown. RESULTS: In this experiment, L. decemlineata and A. chinensis were released onto potato plants under water stress. Thereafter, plant height, stem diameter and yield of potato, growth and reproduction of L. decemlineata, and the longevity of A. chinensis adults were periodically recorded. The results showed that drought had crucial effects on height, stem diameter and yield of potato (p < 0.05); it also had a significant impact on pre-oviposition period, oviposition days, fecundity and life table parameters in L. decemlineata (p < 0.05). Moreover, drought significantly reduced the longevity (p < 0.05) and survival rate of A. chinensis adults. The longevity of adult A. chinensis was only 29.00 ± 3.00 days and the harvest rate of L. decemlineata adults was only 1.42% ± 0.07% under drought treatment. CONCLUSION: In this experiment, we evaluate the bottom-up effects of drought on tritrophic interactions involving potato, L. decemlineata and A. chinensis, and discuss the implications of the findings for integrated pest management programs involving the pest. Promising future research directions are proposed. © 2022 Society of Chemical Industry.

The impact of dietary calcium and phosphorus on mitochondrial-linked gene expression in five tissues of laying hens.

Mitochondria and the energy metabolism are linked to both, the availability of Ca and P to provide the eukaryotic cell with energy. Both minerals are commonly used supplements in the feed of laying hens but little is known about the relationship between the feed content, energy metabolism and genetic background. In this study, we provide a large-scaled gene expression analysis of 31 mitochondrial and nuclear encoded genes in 80 laying hens in the context of dietary P and Ca concentrations. The setup included five tissues and gene expression was analysed under four different diets of recommended and reduced Ca and P concentrations. Our study shows, that mitochondrial gene expression is reacting to a reduction in P and that an imbalance of the nutrients has a higher impact than a combined reduction. The results suggest, that both strains (Lohmann Brown and Lohmann Selected Leghorn) react in a similar way to the changes and that a reduction of both nutrients might be possible without crucial influence on the animals' health or gene expression.

Effects of early-life cecal microbiota transplantation from divergently selected inbred chicken lines on growth, gut serotonin, and immune parameters in recipient chickens.

Recent studies have revealed that fecal microbiota transplantation exerts beneficial effects on modulating stress-related inflammation and gastrointestinal health of the host. The aim of this study was to examine if cecal microbiota transplantation (CMT) presents similar efficiency in improving the health status of egg-laying strain chickens. Chicken lines 63 and 72 divergently selected for resistance or susceptibility to Marek's disease were used as CMT donors. Eighty-four d-old male recipient chicks (a commercial DeKalb XL layer strain) were randomly assigned into 3 treatments with 7 replicates per treatment and 4 birds per replicate (n = 7): saline (control, CTRL), cecal solution of line 63 (63-CMT), and cecal solution of line 72 (72-CMT) for a 16-wk trial. Cecal transplant gavage was conducted once daily from d 1 to d 10, then boosted once weekly from wk 3 to wk 5. The results indicated that 72-CMT birds had the highest body weight and ileal villus/crypt ratio among the treatments at wk 5 (P ≤ 0.05); and higher heterophil/lymphocyte ratios than that of 63-CMT birds at wk 16 (P < 0.05). 72-CMT birds also had higher levels of plasma natural IgG and Interleukin (IL)-6 at wk 16, while 63-CMT birds had higher concentrations of ileal mucosal secretory IgA at wk 5 and plasma IL-10 at wk 16 (P < 0.05), with a tendency for lower mRNA abundance of splenic IL-6 and tumor necrosis factor (TNF)-α at wk 16 (P = 0.08 and 0.07, respectively). In addition, 72-CMT birds tended to have the lowest serotonin concentrations (P = 0.07) with the highest serotonin turnover in the ileum at wk 5 (P < 0.05). There were no treatment effects on the levels of plasma corticosterone and testosterone at wk 16 (P > 0.05). In conclusion, early postnatal CMT from different donors led to different patterns of growth and health status through the regulation of ileal morphological structures, gut-derived serotonergic activities, peripheral cytokines, and antibody production in recipient chickens.

Lippia alba and Lippia gracilis essential oils affect the viability and oviposition of Schistosoma mansoni.

Schistosomiasis is a neglected tropical disease that affects millions of people around the world. Currently, the only drug available for the treatment of this disease is praziquantel, which has low efficacy against immature helminth stages and there are reports of drug resistance. In this study, the chemical composition and the in vitro effect of essential oils (EOs) and major compounds from Lippia gracilis and Lippia alba against schistosomula and adult Schistosoma mansoni worms were evaluated. Adult S. mansoni worms cultured for 8h in the presence of L. gracilis EO (50 and 100 µg/mL) or for 2h with its major compound, carvacrol (100 µg/mL), had a 100% reduction in viability. After interaction with L. alba EO (100µg/mL), there was a reduction of approximately 60% in the viability of adult worms after 24 hours of exposure; citral (50 and 100 µg/mL), its major compound, reduced the viability after 24 hours by more than 75%. Treatment of schistosomula with 100 µg/mL of L. gracilis or L. alba EOs for 6h led to a reduction in parasite viability of 80% and 16% respectively. Both EOs and their major compounds significantly reduced the oviposition of adult worms exposed to a non-lethal concentration (5 µg/mL). In addition, morphological changes such as the destruction of the tegument and disorganization of the reproductive system of male and female worms were visualized. Both EOs showed low cytotoxicity at a concentration of 50 µg/mL. The results encourage further investigation of these plants as a potential source of bioactive compounds against S. mansoni.

Potato plant variety affects the performance and oviposition preference of Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae).

BACKGROUND: Damage by the potato tuber moth Phthorimaea operculella is one of the major constraints to commercial production of potato in many areas of the world. To promote effective pest management practices for P. operculella based on host plant, larval and adult performance of P. operculella fed on Lishu 6, Hezuo 88, Yunshu 304, and Qingshu 9 potato varieties was compared by examining their survival rate, larval feeding, pupal weight, and oviposition preference. RESULTS: Compared with larvae fed on the other three potato plants, those fed on Lishu 6 exhibited the highest survival rate, with almost 61.67% developing to the adult stage. Females also preferred to lay their eggs on Lishu 6 over Hezuo 88, Yunshu 304 and Qingshu 9; and the weight of P. operculella pupa on Lishu 6 plant (0.0085 g) was significantly heavier than that of on others, especially on Qingshu 9 (0.0062 g). Moreover, first instar larvae fed on Lishu 6 showed host preference to Qingshu 9. CONCLUSION: This study demonstrated that Lishu 6 is susceptible to P. operculella, and Qingshu 9 is not relatively susceptible to P. operculella, which suggested that the P. operculella feeding responses to dominant potato varieties in China is different. This variation can be applied for the potato breeding and pest management practice. © 2021 Society of Chemical Industry.

Evolution of antagonistic and mutualistic traits in the yucca-yucca moth obligate pollination mutualism.

Species interactions shape the evolution of traits, life histories and the pattern of speciation. What is less clear is whether certain types of species interaction are more or less likely to lead to phenotypic divergence among species. We used the brood pollination mutualism between yuccas and yucca moths to test how mutualistic (pollination) and antagonistic (oviposition) traits differ in the propensity to increase phenotypic divergence among pollinator moths. We measured traits of the tentacular mouthparts, structures used by females to actively pollinate flowers, as well as ovipositor traits to examine differences in the rate of evolution of these two suites of traits among pollinator species. Morphological analyses revealed two distinct groups of moths based on ovipositor morphology, but no such groupings were identified for tentacle morphology, even for moths that pollinated distantly related yuccas. In addition, ovipositor traits evolved at significantly faster rates than tentacular traits. These results support theoretical work suggesting that antagonism is more likely than mutualism to lead to phenotypic divergence.

Effect of boron supplementation on laying performance of White Leghorn hens fed diet with and without adequate level of calcium.

This study was conducted in White Leghorn layers to ascertain the effect of boron (B) supplementation to calcium (Ca) inadequate diet under standard managemental practices. A total of 80 commercial White Leghorn hens, 25 weeks old with a uniform body weight, were randomly assigned to one of the 4 groups of 20 hens/replicates in each dietary group viz., normal calcium (NC)/Ca adequate, low calcium (LC)/Ca-inadequate, normal calcium with 40 ppm B (NCB) and low calcium with 40 ppm B (LCB). Dietary level of Ca was maintained at two levels, 100 (normal) and 90% (inadequate) of the requirement. Supplementation of B at 40 ppm improved (P < 0.01) egg production of layers from third month of trial as compared to un-supplemented group. Feed conversion ratio of layers was positively (P < 0.05) influenced by B supplementation in Ca-inadequate diet. Egg shell thickness of layers was found to be higher (P < 0.001) in groups supplemented 40 ppm B, irrespective of the level of Ca in the diets. Cracked egg production was also significantly (P < 0.01) lower in B-supplemented groups compared to Ca-inadequate group. Boron supplementation improved Ca retention irrespective of dietary Ca level. Low-Ca diet without boron supplementation resulted in lower retention (P < 0.05) of magnesium and boron. It is concluded that supplementation of 40 ppm B to Ca-inadequate diet ameliorated the lower laying performance in layers and confirms the usefulness of B in such abiotic stress situations.

The evolution of parasitism from mutualism in wasps pollinating the fig, Ficus microcarpa, in Yunnan Province, China.

Theory identifies factors that can undermine the evolutionary stability of mutualisms. However, theory's relevance to mutualism stability in nature is controversial. Detailed comparative studies of parasitic species that are embedded within otherwise mutualistic taxa (e.g., fig pollinator wasps) can identify factors that potentially promote or undermine mutualism stability. We describe results from behavioral, morphological, phylogenetic, and experimental studies of two functionally distinct, but closely related, Eupristina wasp species associated with the monoecious host fig, Ficus microcarpa, in Yunnan Province, China. One (Eupristina verticillata) is a competent pollinator exhibiting morphologies and behaviors consistent with observed seed production. The other (Eupristina sp.) lacks these traits, and dramatically reduces both female and male reproductive success of its host. Furthermore, observations and experiments indicate that individuals of this parasitic species exhibit greater relative fitness than the pollinators, in both indirect competition (individual wasps in separate fig inflorescences) and direct competition (wasps of both species within the same fig). Moreover, phylogenetic analyses suggest that these two Eupristina species are sister taxa. By the strictest definition, the nonpollinating species represents a "cheater" that has descended from a beneficial pollinating mutualist. In sharp contrast to all 15 existing studies of actively pollinated figs and their wasps, the local F. microcarpa exhibit no evidence for host sanctions that effectively reduce the relative fitness of wasps that do not pollinate. We suggest that the lack of sanctions in the local hosts promotes the loss of specialized morphologies and behaviors crucial for pollination and, thereby, the evolution of cheating.

Intergenerational Transmission of Resistance of Callosobruchus maculatus to Essential Oil Treatment.

Due to the rise of numerous legal restrictions as well as the increasing emergence of resistant populations, the number of available pesticides is decreasing significantly. One of the potential alternatives often described in the literature are essential oils (EOs). However, there is a lack of research addressing the potential emergence of resistance to this group of substances. In this paper, we investigated the multi-generational effects of sublethal concentrations of rosemary oil (Rosmarinus officinalis) on physiological and biochemical parameters of the cowpea weevil (Callosobruchus maculatus) such as egg laying, hatchability, oxygen consumption and acetylcholinesterase activity. Imago, which as larvae were exposed to EO at concentrations equivalent to LC25, showed significantly lower mortality. The results obtained indicate the potential development of resistance in insects exposed to EO in concentrations corresponding to LC25. In addition, in the case of the group treated with an EO concentration corresponding to LC3.12, a stimulation effect of the above-mentioned parameters was observed, which may indicate the occurrence of a hormesis effect. The obtained results may be an important reference for the development of future guidelines and EO-based insecticides.