Phenology model development for Neodryinus typhlocybae: Evaluation of phenological synchrony with its host, Metcalfa pruinosa.

The invasive species Metcalfa pruinosa has inflicted significant economic losses in various European and Asian regions. To combat this pest, the parasitoid wasp Neodryinus typhlocybae has been effectively introduced in Europe. Despite its success, research on the field occurrence patterns of N. typhlocybae, particularly its phenology, remains scarce. This study aims to develop a degree-day model for predicting the adult emergence of N. typhlocybae from overwintering cocoons and to assess the phenological synchrony between N. typhlocybae adults and the nymphal stages of M. pruinosa in Korea. In this study, we estimated the thermal parameters of N. typhlocybae under field temperatures and six constant temperatures (13.92, 17.71, 18.53, 20.53, 22.78, and 24.03 °C) conditions. The lower developmental temperature was estimated using the values of the coefficient of variation for the cumulative degree days of emerged individual adults. The estimated lower developmental threshold temperature was 12.3 °C. With this developmental threshold, a degree-day model was developed, and this model well-predicted emergence in field conditions. By simulating this developed model with the actual occurrence of the nymphal stages of its host, M. pruinosa, adult wasp emergence was estimated to be 1.5 weeks later than the first instar nymph of the host but faster than other nymphal stages of M. pruinosa. Thus, the findings in this study would be helpful in determining the possibility of establishing N. typhlocybae and improving the management efficiency of M. pruinosa.

Disruptive Effects of Two Curcuminoids (Demethoxycurcumin and Bisdemethoxycurcumin) on the Larval Development of Drosophila melanogaster.

Juvenile hormones (JHs) play a central role in insect development, reproduction, and various physiological functions. Curcuminoids generally exhibit a wide range of biological activities, such as antioxidant, anti-inflammatory, antibacterial, and insecticidal, and they exhibit insect growth inhibitory effects. However, research on insecticidal properties of curcuminoids has been limited. Moreover, to the best of our knowledge, studies on JHs of insects and curcuminoids are lacking. Therefore, this study aimed to identify the substances that act as JH disruptors (JHDs) from edible plants. Demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC), two curcuminoids from the turmeric plant Curcuma longa L. inhibited the formation of a methoprene-tolerant (Met)-Taiman (Tai) heterodimer complex in Drosophila melanogaster, as shown through in vitro yeast two-hybrid assays. An artificial diet containing 1% (w/v) DMC or BDMC significantly reduced the number of D. melanogaster larvae in a concentration-dependent manner; larval development was disrupted, preventing the progression of larvae to pupal stages, resulting in an absence of adults. Building on the results obtained in this study on curcuminoids, researchers can use our study as a reference to develop eco-friendly pesticides.

Assessment of acute and chronic toxicity of cyantraniliprole and sulfoxaflor on honey bee (Apis mellifera) larvae.

BACKGROUND: Recently, cyantraniliprole (CYA) and sulfoxaflor (SUL) have been considered as alternatives to neonicotinoid insecticides. In this study, we evaluated the acute and chronic toxicities of CYA and SUL on honey bee (Apis mellifera L.) larvae reared in vitro. RESULTS: In the acute toxicity test, the following test doses were used to determine the median lethal dose (LD50 ): CYA 0.007, 0.014, 0.028, 0.056 and 0.112 µg larva-1 ; SUL 2.5, 5, 10, 20 and 40 µg larva-1 . In the chronic toxicity test, the following test doses were used to determine the LD50 : CYA 0.00512, 0.0128, 0.032, 0.08 and 0.2 µg larva-1 ; SUL 0.0625, 0.125, 0.25, 0.5 and 1.0 µg larva-1 . The acute LD50 values of CYA and SUL were 0.047 and 11.404 µg larva-1 , respectively. Larvae acutely exposed to SUL had significantly lower body weight than controls, but those exposed to CYA showed no difference. The no observed adverse effect level (NOAEL) and LD50 values of the chronic toxicity tests for each insecticide were 0.00512 and 0.064 µg larva-1 for CYA, and 0.0625 µg larva-1 and 0.212 µg larva-1 for SUL, respectively. Larvae chronically exposed to SUL emerged as bees with deformed wings, reaching adult deformation rates of over 50%; however, CYA had no effect on adult deformation. CONCLUSION: Exposure to CYA increased larval mortality but did not cause any adult deformation, whereas SUL exposure increased pupal mortality and caused wing deformation in newly emerged bees. Our study may be useful for the assessment of pesticide toxicity by providing valuable findings on the effects of these insecticides on honey bee larvae. © 2022 Society of Chemical Industry.

Developmental Toxic Effects of Thiram on Developing Zebrafish (Danio rerio) Embryos.

Thiram, an oxidized dimer of dithiocarbamate, has fungicidal and ectoparasiticidal roles. This study aimed to determine the effects of thiram on the development of zebrafish (ZF) embryos. The developmental toxicity test was performed in accordance with the OECD 236 test guidelines, and ZF embryos were subjected to several thiram concentrations and a DMSO (0.01%) control. Subsequently, embryo mortalities and developmental anomalies were evaluated at different hours post fertilization (hpf). Thiram was highly toxic to ZF, with calculated median lethal concentrations (LC50) of thiram at 48 and 96 h as 13.10 ± 2.17 and 8.87 ± 2.09 µg/L, respectively. Thiram-treated embryos/larvae exhibited a variety of deformities, such as abnormal somites, reduced eye pigment, abnormal tail shape, yolk sac edema, hatching defects, and curved spines, with a median effective concentration (EC50) of 3.88 ± 1.23, 5.04 ± 1.82, 6.23 ± 0.92, 5.24 ± 2.22, 1.39 ± 0.25, and 2.60 ± 0.82 µg/L, respectively. Teratogenic index (TI) values ranged from 1.42 to 6.66 for the scored deformities. At 48 hpf, the average heartbeat of the control group was 177.20 ± 5.63 per minute, while the highest thiram-treated group (40 µg/L) was 99.50 ± 18.12 per minute. In addition, cardiac-related issues, such as pericardial edema and abnormal blood flow, were observed in thiram-treated ZF embryos. Overall, these findings suggest that thiram is teratogenic to ZF.

Transcriptome-Based Identification of Genes Responding to the Organophosphate Pesticide Phosmet in Danio rerio.

Organophosphate pesticides (OPPs) are one of the most widely used insecticides. OPPs exert their neurotoxic effects by inhibiting acetylcholine esterase (AChE). Most of the gross developmental abnormalities observed in OPP-treated fish, on the other hand, may not be explained solely by AChE inhibition. To understand the overall molecular mechanisms involved in OPP toxicity, we used the zebrafish (ZF) model. We exposed ZF embryos to an OPP, phosmet, for 96 h, and then analyzed developmental abnormalities and performed whole transcriptome analysis. Phenotypic abnormalities, such as bradycardia, spine curvature, and growth retardation, were observed in phosmet-treated ZF (PTZF). Whole transcriptome analysis revealed 2190 differentially expressed genes (DEGs), with 822 and 1368 significantly up-and downregulated genes, respectively. System process and sensory and visual perception were among the top biological pathways affected by phosmet toxicity. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed significant enrichment of metabolic pathways, calcium signaling pathway, regulation of actin cytoskeleton, cardiac muscle contraction, drug metabolism-other enzymes, and phototransduction. Quantitative real-time PCR results of six DEGs agreed with the sequencing data expression profile trend. Our findings provide insights into the consequences of phosmet exposure in ZF, as well as an estimate of the potential risk of OPPs to off-target species.

Horizontal Honey-Bee Larvae Rearing Plates Can Increase the Deformation Rate of Newly Emerged Adult Honey Bees.

Rearing honey bee larvae in vitro is an ideal method to study honey bee larval diseases or the toxicity of pesticides on honey bee larvae under standardized conditions. However, recent studies reported that a horizontal position may cause the deformation of emerged bees. Accordingly, the purpose of this study was to evaluate the emergence and deformation rates of honey bee (Apis mellifera ligustica) larvae reared in horizontal and vertical positions. The study was conducted under the same laboratory conditions with three experimental groups, non-capped or capped horizontal plates and capped vertical plates. However, our results demonstrated that the exhibited adult deformation rates of the horizontal plates were significantly higher (27.8% and 26.1%) than those of the vertical plates (11.9%). In particular, the most common symptoms were deformed wings and an abnormal abdomen in the horizontal plates. Additionally, adults reared on horizontal plates were substantially smaller (10.88 and 10.82 mm) than those on vertical plates (11.55 mm). Considering these conclusions, we suggest that a vertical rearing method is more suitable when considering the deformation rates of the control groups to verify the sublethal effects of pesticides on honey bees.

Predation, development, and oviposition by the predatory mite Amblyseius swirkii (Acari: Phytoseiidae) on tomato russet mite (Acari: Eriophyidae).

Predation, development, and oviposition experiments were conducted to evaluate Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) as a potential biological control agent for tomato russet mite, Aculops lycopersici (Massee) (Acari: Eriophyidae), which can be a serious pest of greenhouse tomatoes. Results showed that A. swirskii attacked all developmental stages of A. lycopersici and had a type II functional response at the prey densities tested. The attack rate and handling time estimates from the random predator equation were 0.1289/h and 0.2320 h, respectively, indicating that A. swirskii can consume 103.4 individuals per day. Predation rates of A. swirskii on A. lycopersici in the presence of alternative food sources such as pollen, first-instar thrips, or whitefly eggs were 74, 56, and 76%, respectively, compared with the predation rate on A. lycopersici alone. A. swirskii successfully completed their life cycle on either A. lycopersici or cattail (Typha latifolia L.) pollen. At 25 degrees C and 70% RH, developmental time of female A. swirskii fed on A. lycopersici or on cattail pollen was 4.97 and 6.16 d, respectively. For the first 10 d after molting to the adult stage, A. swirskii fed on A. lycopersici had higher daily oviposition rate (2.0 eggs per day) than on pollen (1.5 eggs per day). From this laboratory study, it can be concluded that A. swirskii has promising traits as a predator against A. lycopersici and that their populations can be maintained using alternative food sources such as cattail pollen. We suggest that the effectiveness of A. swirskii against A. lycopersici under field conditions needs next to be investigated.

Clinical feasibility of pinhole glasses in presbyopia.

PURPOSE:: To investigate the ocular physiologic changes and subjective symptoms of wearing multiple-pinhole glasses in subjects with presbyopia. METHODS:: This prospective study included 32 eligible subjects with presbyopia. Objective ocular functions and a survey of ocular discomfort were performed at baseline. All participants underwent the same examinations after reading while wearing the pinhole glasses and not wearing these glasses at a 1-week interval in random order. RESULTS:: The pinhole glasses improved uncorrected distance and near visual acuity in presbyopia. These glasses also required 15% less accommodative power over the near stimulus of 25 cm than did eyes without pinholes. Compared to reading without pinhole glasses, reading with pinhole glasses led to the following changes: increase in monocular near point of accommodation from 4.39 ± 0.78 diopter (D) to 5.19 ± 1.12 D, increase in depth of focus from 1.42 ± 0.44 D to 2.00 ± 0.33 D, and increase in amplitude of fusional convergence from 13.38 ± 6.88 prism D to 21.62 ± 10.00 prism D. In contrast, the reading speed decreased, inter-blink interval increased, tear break-up time shortened, and subjective ophthalmic symptoms worsened with pinhole glasses compared to without. CONCLUSION:: In presbyopia, pinhole glasses improve visual acuity and accommodation-related parameters by pseudo-accommodation and the pinhole effect. However, the low legibility, increased inter-blink interval, and shortened break-up time of pinhole glasses cause an uncomfortable feeling and excessive eye fatigue. Pinhole glasses have strengths and limitations that must be considered to provide appropriate guidance in patients with presbyopia. Clinical trial registration was done at www.ClinicalTrials.gov (identifier: NCT02722291).

Change in eyelid parameters after orbital decompression in thyroid-associated orbitopathy.

PURPOSE: To investigate quantitative changes in eyelid parameters after orbital decompression surgery in thyroid-associated orbitopathy using the PC-based program, Eyelid Analysis Software (EAS). METHODS: This study included 202 eyes of 109 thyroid-associated orbitopathy patients. Digital photographs of the patients in primary gaze were taken just before and after orbital decompression surgery, and exophthalmos degree was measured by Hertel exophthalmometry (Hertel Exophthalmometer SKU:52400; Oculus, Arlington, VA, USA). The custom-made PC-based software EAS (Biomedical Research Institute, Seoul, Korea) was used to analyze eyelid parameters. The 11 parameters included pupil to inferior eyebrow distance (PBD), margin reflex distance 1 (MRD1), margin reflex distance 2 (MRD2), palpebral fissure (PF), total lid length, upper and lower lid length, area, medial area, center area, and lateral area. RESULTS: Univariate linear regression analysis showed a significant positive association between amount of exophthalmos reduction and the following parameters: area (p = 0.007); MRD2 (p = 0.043); upper lid length (p = 0.045); lower lid length (p = 0.006); medial area (p = 0.045); and lateral area (p = 0.005). Multivariate linear regression analysis showed only two parameters, lower lid length (p = 0.022) and lateral area (p = 0.019) were associated with exophthalmos reduction. CONCLUSIONS: A reduction in the inferior lateral part of the eyelid (lateral area + lower lid length) occurred after orbital decompression surgery in patients with thyroid-associated orbitopathy.

Topographic analysis of eyelid position using digital image processing software.

PURPOSE: To propose a novel analysis technique for objective quantification of topographic eyelid position with an algorithmatically calculated scheme and to determine its feasibility. METHODS: One hundred normal eyelids from 100 patients were segmented using a graph cut algorithm, and 11 shape features of eyelids were semi-automatically quantified using in-house software. To evaluate the intra- and inter-examiner reliability of this software, intra-class correlation coefficients (ICCs) were used. To evaluate the diagnostic value of this scheme, the correlations between semi-automatic and manual measurements of margin reflex distance 1 (MRD1) and margin reflex distance 2 (MRD2) were analysed using a Bland-Altman analysis. To determine the degree of agreement according to manual MRD length, the relationship between the variance of semi-automatic measurements and the manual measurements was evaluated using linear regression. RESULTS: Intra- and inter-examiner reliability were excellent, with ICCs ranging from 0.913 to 0.980 in 11 shape features including MRD1, MRD2, palpebral fissure, lid perimeter, upper and lower lid lengths, roundness, total area, and medial, central, and lateral areas. The correlations between semi-automatic and manual MRDs were also excellent, with better correlation in MRD1 than in MRD2 (R = 0.893 and 0.823, respectively). In addition, significant positive relationships were observed between the variance and the length of MRD1 and 2; the longer the MRD length, the more the variance. CONCLUSION: The proposed novel optimized integrative scheme, which is shown to have high repeatability and reproducibility, is useful for topographic analysis of eyelid position.