Journal of Asia-pacific Entomology最新文献

In this study, we compared the diversity and abundance of two groups of Lepidopteran insects—butterflies and moths—across deciduous (DBL) and evergreen broad-leaved (EBL) tree communities in warm temperate forests. Over three years (from 2018 to 2020) at the Wando Arboretum, we used transect and point methods to sample butterflies and light traps to sample moths. Our findings revealed that the total estimated species richness was higher in EBL compared to DBL. Non-metric multidimensional scaling (NMDS) analysis confirmed distinct moth assemblages between the two tree communities, while butterfly assemblages did not exhibit such separation. The seasonal diversity patterns of butterflies in both forests differed significantly, whereas those of moths exhibited a similar trend with a peak in June. Beta diversity components indicated high turnover rates in moth assemblages across both tree communities and high nestedness in butterfly assemblages within the DBL. Although the diet breadth of butterflies and moths did not significantly differ between the two tree communities, the number of butterfly species per host plant was higher in DBL and that of moths was higher in EBL. Considering the ongoing vegetation transition from DBL to EBL, changes in forest structure—such as canopy openness and tree density—may adversely impact insect communities within DBL.

The influence of cell structure size on the morphological development of honey bees has been widely studied. However, the effect of the honey bees' body size on the cell size they build remains unclear. This study investigated the influence of the body size of Apis cerana cerana on the structure size of newly built honey cells, worker cells, and drone cells. Accordingly, we established colonies of A. c. cerana with large and small body-size workers. We then analyzed the birth weight and seven external morphological characteristics of workers, as well as the depth and diameter of their newly built honey cells, worker cells, and drone cells. We found significant differences in the birth weight, proboscis length, thorax width, right forewing length, femur length, tibia length, and metatarsus length of the right hindleg, and total length of the 3^rd and 4^th tergite of workers from large-body-size colonies (LBSC) and small-body-size colonies (SBSC). Also, the depth and diameter of the newly built cells by LBSC were significantly larger than those by SBSC. The body size of workers positively correlated with the size of newly built cells. This study emphasizes the influence of workers' body size on the structural dimensions of newly constructed cells, providing insights into the comb-building biology of A. c. cerana.

The yellow mite Polyphagotarsonemus latus Banks (Acari: Tarsonemidae) is a destructive pest, affecting fiber-producing jute plants in Bangladesh. Development, survivorship and adult reproduction of this pest on five common jute cultivars (Corchorus capsularis: CVL-1, BJC-7370, BJC-2197, C. olitorius: O-795, O-9897) were investigated under laboratory conditions and life-table parameters were estimated. Developmental periods from egg to adult emergence ranged from 2.7 to 3.9 days with the sex ratio (proportion of females) being 0.71 to 0.78. Adult longevity varied from 8.8 to 5.4 days for both females and males. Immature survivorship ranged from 84.4 to 97.9 % with the lowest on CVL-1. Daily fecundity was highest (4.2) on BJC-7370 while lifetime fecundity was greatest on O-795 cultivar. The jute cultivars did not show any significant effects on the lifespan of male adults, but did on female adult performance such as reproduction, longevity and life table parameters. Based on developmental period, doubling time and r_m value, BJC-7370 supported the fastest population growth, and O-9897 and CVL-1 cultivars the slowest population growth. These results could be possibly related to the resistance potential to this important herbivore pest. Additional investigations should explore the nutritional and digestion-inhibition mechanisms that account for the differences in performance of the phytophagous mites on jute cultivars.

Camptothecin, a quinoline alkaloid, has strong action against Spodoptera frugiperda, a polyphagous pest found globally. Real-time quantitative PCR (RT-qPCR) is a popular and dependable technique for analyzing the mRNA expression of target genes. While RT-qPCR normalization requires reference genes with consistent expression. Many investigations have discovered that pesticides can change the expression patterns of reference genes. To date, the effects of CPT treatments on the expression stability of reference genes in S. frugiperda larvae are unclear. This study chose eight candidate reference genes, including alpha-tubulin (α-TUB), beta-1-tubulin (β-1-TUB), Actin, elongation factor 1 alpha (EF1α), elongation factor 2 (EF2), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ribosomal protein L3 (RPL3), and ribosomal protein L13 (RPL13). Five approaches were used to investigate expression stability in S. frugiperda larval samples treated with CPT: ΔCt, BestKeeper, geNorm, NormFinder, and RefFinder, respectively. Furthermore, the ideal number of reference genes was determined using GeNorm. Our findings revealed that two reference genes were sufficient to normalize RT-qPCR in samples treated with CPT. The recommended reference gene combinations for different samples are as follows: α-TUB and β-1-TUB for CPT-treated larval samples; β-1-TUB and RPL13 for samples of larval cuticle tissues; RPL3 and RPL13 for the larval fat body samples; EF1α and RPL3 for the larval malpighian tube samples; and EF2 and Actin for the larval midgut samples. Our results laid the groundwork for the mRNA expression analysis of target genes in S. frugiperda impacted by CPT exposure, contributing to the research of the molecular action mechanism of CPT in S. frugiperda.

The genus Nysius Dallas is the largest group in the subfamily Orsillinae (Lygaeoidea: Lygaeidae), and is a well-known agricultural pest that mainly feeds on grains. In Korea, N. plebeius and N. hidakai are well known to be agricultural pests. In the present study, we recognized six species of the genus Nysius Dallas from the Korean Peninsula. Among these, N. thymi (Wolff, 1804) was reported for the first time in the fauna. We provided new host plants, a key to the species of the genus from Korea, descriptions and diagnoses of these species using photographs of adult specimens and genitalia. We also present discussion on wrong host plants records of agricultural crops caused from misidentifications between N. plebeius and N. hidakai in Korea. Additionally, we confirmed that N. eximius and N. expressus are not occurring from South Korea based on the South Korean materials.

The breeding system of Bruguiera cylindrica, its associated foragers, and their foraging activity were carried out from 2018−2021 in the mangroves of Chettuva, of Thrissur district in the State of Kerala. The flowering of B. cylindrica commences during October and found to cease by the end of January. Bagging experiment revealed that they prefer xenogamous mode (88%) of reproduction though they had a small percentage of fruit set via autogamy (16%).Thirty five species of insects were recorded on the flowers of B. cylindrica. Among them, eleven species were foraging on the flowers of B. cylindrica. The most abundant foraging species were Chrysomya megacephala, Apis florea and Campsomeriella collaris.

C. megacephala had significantly higher visitation rate (7.52 flowers/min) whereas Dolichopus sp. recorded significantly higher handling time (11.71 s). The highest pollen load was obtained from Chrysomya megacephala (161.50 ± 4.90). The peak foraging activity was recorded during 10.00 hrs. − 11.00 hrs. in the morning and 16.00 hrs. − 17.00 hrs. in the evening. The findings of the study complement the role and significance of insect foragers in the breeding of mangrove species.

Fruit flies and other miniscule flying insects often cause a nuisance in the kitchen areas of our dwellings. To mitigate the invasion of indoor insect pests, behavioral modifications using spatial repellents containing natural products are emerging as alternatives to chemical insecticides especially around the kitchens and food storage areas. However, the absence of standardized testing methods for spatial repellency has undermined the reliability of these products. We introduced three distinct laboratory-scale repellency assays and their relevancy to simulated-use conditions. Out of eleven commercial products tested, five showed effectiveness in laboratory assays, and three of these were further proven effective in simulated-use tests as well. Another issue limiting the utility of commercially available spatial repellents was the lack of clear and comprehensive use instructions on product labels, potentially leading to ineffective applications. We observed that increasing the applied quantity improved the efficacy of one product that was initially determined to be ineffective in a simulated-use test. Based on our findings, we propose three strategies for regulations of spatial repellents: 1) consideration of mixture effects beyond single active ingredients especially using the natural products as their active ingredients, 2) the use of multiple testing systems, while acknowledging the limitations of laboratory assays in predicting real-world efficacy, and 3) ensuring product labels provide detailed and clear instructions for effective use.

Honey bee population inhabiting among different geographic regions often exhibit distinctive traits and phenotypes as a means of enhancing their adaptation to local environmental conditions. Morphological difference of worker was used to reflect the honey bee population locality adaptation and as one of the important markers of species evolution. Here, four comb cell and seven morphology characters of honey bee Apis cerana from two adjacent populations of Yunnan Province were measured to explore the effect of local adaptation on worker comb cell and morphology. Results showed that the characters of worker comb cell and morphology was significant difference between samples from these two local populations of A. cerana. It was separated into two groups which corresponding into the general A. cerana geographic population of Yungui Plateau and South Yunnan base on worker comb cell and morphology character. The worker comb cell size and morphology of A. cerana from Qujing were found to be significantly larger than those from Cangyuan. The indices that showed the most significantly different between populations were cell depth and right forewing length. Moreover, a strong positive correlation was observed between the cell diagonal diameter and the right forewing length, with a correlation coefficient 0.575. In conclusion, honey bee A. cerana population appear high variation in comb cell and morphology to adapt the locality environment. The forewing length of worker was the most significant variation indices between geographic populations, and could be as an indicator of worker cell and morphology among different A. cerana geographic populations.

Leafhopper species, viz., Hishimonus phycitis, Orosius albicinctus, and Amrasca bigutulla bigutulla, and sesame phyllody disease, damage sesame in tropical regions of India. Among the leafhopper species, H. phycitis incidence was maximum during 2022–23, peaked (70.36 nos./3 leaves) during the 40th Standard Meteorological Weeks (SMW), followed by O. albicinctus, which peaked in the 33rd SMW (53.14 nos./3 leaves) during 2021–2022. The impact of weather factors on the leafhoppers showed that minimum temperature (MnT) positively correlated with H. phycitis (r = 0.33***), O. albicinctus (r = 0.37***), populations A. bigutulla bigutulla (r = 0.22*), and phyllody percentage disease incidence (PDI) (r = 0.16). Rainfall (RF) and wind speed (WS) were negatively associated with leafhoppers, O. albicinctus, and A. bigutulla bigutulla, respectively. Morning (RHm) and evening (RHe) relative humidity were positively associated with all leafhopper species. The MnT was inversely associated with O. albicinctus (r = 0.37***) populations. The PDI was positively associated and significantly associated with the weather factors except WS. The autoregressive integrated moving average model with exogenous variables (ARIMAX) (0, 1, 0) of H. phycitis showed that MnT, RHe, and RF greatly affected the pest’s growth. The ARIMAX (3, 0, 1) of O. albicinctus showed that MnT and RHe significantly impacted the incidence. The ARIMAX (3, 0, 2) model of A. bigutulla bigutulla showed that MxT, MnT, RHm, and RHe substantially affected their occurrence. The ARIMAX (2, 0, 1) model of PDI revealed that MxT, MnT, RHm, RHe, and RF substantially influenced the disease’s incidence. Insect pests exhibit varied patterns of occurrence and severity in multi-cropping systems due to substantial differences in agro-climatic variables between locations. Comprehending the impact of weather patterns on sesame leafhoppers and PDI is crucial for developing successful management methods. Based on weekly events and climatic factors, the ARIMAX model was developed to anticipate the presence of leafhopper species and PDI on sesame.

The study aims to provide a basis for the large-scale artificial breeding of Coccinella septempunctata, the composition of an artificial diet for the ladybird was optimised by adding different fats to the diet. The effects of different dietary fats on the biology of ladybirds were evaluated by supplementing artificial diets with fats. The results show that the coconut, palm, perilla, linseed, lard and sesame oils should not be added to the artificial diet of ladybird larvae because of deleterious effects on ladybirds. The addition of 6 g olive oil (3 % of diet weight) improved larvae survival rate, and the addition of 4 g beef tallow (2 % of diet weight) increased ladybird pupation and emergence rates. In adult stage, the addition of 4 g coconut oil (2 % of diet weight) improved survival rates. Whereas 2–4 g olive oil (1–2 % of diet weight), 2–6 g lard (1–3 % of diet weight) and 6 g beef tallow oil (3 % of diet weight) improved oviposition and hatchability. In conclusion, the demand for fats is different in the larval and adult stages of the C. septempunctata. The findings of this study provide a valuable reference for the addition of exogenous fats to the ladybird artificial diet.