当前工业化养殖胡瓜钝绥螨的产量巨大,导致现有人工品质管控方式无法及时准确地对螨虫养殖品质进行监测.设计研发一款螨虫监控系统,包含螨虫麦麸分离装置、显微视觉装置、改进的YOLOv5 螨虫检测模型.通过对YOLOv5 模型的网络结构进行分析,在原YOLOv5 模型上将嵌入ECANet注意力机制的MobileNetv3-Large网络作为主干特征提取网络,加强网络提取特征能力,进一步通过裁剪模型预测头的冗余部分,提升模型对中小目标检测性能.实验结果表明:改进后的M3ECA-YOLOv5-2H模型对比原YOLOv5 模型,在平均检测精度mAP50 和mAP75上提高了 0.68 和 4.62 个百分点;在模型大小上降低 18.9 MB,占用更低内存;在单张图片推理速度上提升 4 ms.此外对比其他 5 种通用目标检测模型,M3ECA-YOLOv5-2H模型在检测精度和检测速度等指标上整体表现更佳,具有很好的应用价值.

Implementing a predator-mediated pathogen dissemination system can meet the goal of simultaneous biocontrol of harmful mites and other pests. But for the system to be effective, it must satisfy the requirement of high lethality of the pathogen to the target pest(s) with low lethality to predatory mites in a suitable environment. Prior testing showed that the fungal entomopathogen Isaria fumosorosea (Wize) Brown & Smith exhibited high toxicity to aphids yet low toxicity to the predatory mite Neoseiulus cucumeris (Oudemans). In practical application, the humidity conditions of conidia carried by predatory mites to plants are not necessarily constant. Therefore, we set two different humidity conditions to observe the changes of spore attachment quantity and the differences of germination and infection between predatory mites and aphids after their bodies were stained with spores. Under 50±1% relative humidity (RH), predatory mites cleaned most spores in a short time; 24 hours after dusting, the number of spores (mean ± SD) on body was (0.64±0.10)×103, just (4.43±0.35)% of that at 0h, but spores on aphids were kept (16.58±1.48)% ((6.46±0.91)×103 spores) of that at beginning. There was a significant difference in the percentage of spores retained on aphids and predatory mites (p=0.000<0.01). Humidity could affect the cleaning behavior; under 95± 1% RH (the suitable humidity for conidia germination), more spores persisted than that under the 50 ± 1% RH condition; at 24h, the numbers of spores on each predatory mite and aphid were (1.00±0.10)×103 and (10.02±2.87)×103. Here, under a scanning electron microscope, we found that spores on the aphid’s body germinated 36 hours after dusting under 95± 1% RH, and the I. fumosorosea mycelium had spread after 48 hours; many new mycelium and spores were produced after 72 hours. In stark contrast, few spores germinated on the mite’s body, thus leading to very little damage to its surface. Different cleaning behavior and different morphological structure of body wall can both affect the attachment and infection of I. fumosorosea to aphids and predatory mites. In the future, chemical substance, enzyme and other factors should also be researched to explain the difference of infection of entomopathogenic fungi to different species.

美丽革伊螨Gamasiphis pulchellus(Berlese,1887)广泛分布于土壤中,并能捕食线虫.对采自西藏自治区亚东县苔藓、落叶、枯树皮、树洞土壤中美丽革伊螨的标本进行重新描述,主要描述前后若螨、雌螨和雄螨.

To identify the searching ability of avermectin-resistant and susceptible strains of Neoseiulus cucumeris (Oudemans), the responses of the two strains to stimuli from Tetranychus urticae Koch on sweet potato leaves were examined in the laboratory. The results showed that avermectin-resistant and susceptible adult N. cucumeris females responded to different stages and intact webs (spider mite, egg, feces, and leaf damage) of T. urticae, but not to the destroyed webs and feces of and feeding damage by T. urticae. Moreover, no significant differences were observed in the responses of the avermectin-resistant and susceptible strains of N. cucumeris. Both strains of N. cucumeris were often observed inside the intact webs of T. urticae. These results show that the avermectin-resistant and susceptible strains of N. cucumeris have the ability to search actively for T. urticae on sweet potato leaves. This behavior clearly increases the searching efficiency of N. cucumeris and may help its use in the biocontrol of T. urticae.

Abstract Background Predatory mites (Acari: Phytoseiidae) are the most important beneficial arthropods used in augmentative biological pest control of protected crops around the world. However, the genomes of mites are far less well understood than those of insects and the evolutionary relationships among mite and other chelicerate orders are contested, with the enigmatic origin of mites at one of the centres in discussion of the evolution of Arachnida. Results We here report the 173 Mb nuclear genome (from 51.75 Gb pairs of Illumina reads) of the predatory mite, Neoseiulus cucumeris, a biocontrol agent against pests such as mites and thrips worldwide. We identified nearly 20.6 Mb (~ 11.93% of this genome) of repetitive sequences and annotated 18,735 protein-coding genes (a typical gene 2888 bp in size); the total length of protein-coding genes was about 50.55 Mb (29.2% of this assembly). About 37% (6981) of the genes are unique to N. cucumeris based on comparison with other arachnid genomes. Our phylogenomic analysis supported the monophyly of Acari, therefore rejecting the biphyletic origin of mites advocated by other studies based on limited gene fragments or few taxa in recent years. Our transcriptomic analyses of different life stages of N. cucumeris provide new insights into genes involved in its development. Putative genes involved in vitellogenesis, regulation of oviposition, sex determination, development of legs, signal perception, detoxification and stress-resistance, and innate immune systems are identified. Conclusions Our genomics and developmental transcriptomics analyses of N. cucumeris provide invaluable resources for further research on the development, reproduction, and fitness of this economically important mite in particular and Arachnida in general.

When males fight for access to females, such conflict rarely escalates into lethal fight because the risks and costs involved, that is, severe injury or death, are too high. The social spider mite, Stigmaeopsis miscanthi, does exhibit lethal male fights, and this male-male aggressiveness varies among populations. To understand the evolution of lethal fighting, we investigated aggressiveness in 42 populations and phylogenetic relationships in 47 populations along the Japanese archipelago. By analysis of the male weapon morph, a proxy for aggressiveness, we confirmed the existence of a mildly aggressive (ML) form, besides the low aggression (LW) and high aggression (HG) forms reported earlier. To evaluate demographic history of these three forms, we employed the approximate Bayesian computation approach using mtCOI sequences and taking into consideration the postlast glacial expansion history of the host plant, Miscanthus sinensis. As results, hierarchical split models are more likely to explain the observed genetic pattern than admixture models, and the ML form in the subtropical region was considered the ancestral group. The inferred demographic history was consistent with the one reconstructed for the host plant in a previous study. The LW form was split from the ML form during the last glacial period (20,000-40,000years BP), and subsequently, the HG form was split from the ML form at the end of or after the last glacial period (5,494-10,988years BP). The results also suggest that the mite invaded Japan more than once, resulting in the present parapatric distribution of LW and HG forms in eastern Japan.

异色瓢虫具有自残习性,在大量饲养中需根据此特性探索出适宜的密度来保证成虫获得率和卵的获得量.在室内测定了在100 mL饲养盒中以地中海粉斑螟卵为食物的异色瓢虫幼虫不同密度下的成虫获得率以及雌雄成虫不同配比时的产卵量.幼虫饲养时,一个饲养盒中平均最多获得7只成虫,随着初始虫量的增多,成虫获得率呈下降趋势,单头饲养的获得率最高.成虫饲养时,1雌1雄、2雌2雄和3雌3雄处理的指标呈规律性变化,虫量越多,产卵前期越短、产卵期越长,总产卵量越大,单雌日产卵量越小,后代的孵化率均达80％以上.4雌4雄处理虫量多,相互干扰,导致产卵前期长、产卵期短、产卵量少,孵化率低、雌性比低.2雌1雄处理与相同雌虫数量的2雌2雄处理相比,单雌日产卵量、总产卵量、后代孵化率、雌性比均低于2雌2雄处理.3雌1雄、3雌2雄处理与3雌3雄处理相比,结果亦然.雌雄等量比少雄的处理产卵多且优,但单雌产卵量、后代孵化率、雌雄性比以单对饲养最高.

XIA CHEN, YU-PING ZHANG, LI SUN, YUAN ZHEN, YAN-XUAN ZHANG & JIANZHEN LIN 1 Research Center of Engineering and Technology of Natural Enemy Resource of Crop Pest in Fujian, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China; correspondence to Xia Chen <405593754@qq.com>, Yan-Xuan Zhang 2 Plant Protection Institute, Guangdong Academy of Agricultural Sciences, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, Guangdong, China.

We provided a new diagnosis of the genus Stigmaeopsis. Then we described two new species that are very closely related to Stigmaeopsis miscanthi (Saito) from Miscanthus spp. in Japan and China. The Japanese species, named Stigmaeopsis sabelisi Saito and Sato n. sp., was previously referred to as Stigmaeopsis miscanthi low aggressiveness form , and is characterized by its low male-to-male aggression behavior. The other species, Stigmaeopsis continentalis Saito and Lin n. sp., was found in China (Fujian district). Thus four species could be discriminated from the species inhabiting Miscanthus and reed grasses. However, the two new species and S. miscanthi resemble each other very closely, thus they are considered to be sibling species. To identify them several naive characters, geographic distribution and genetic data are needed. An updated key to all known species of Stigmaeopsis is also proposed.

根据中国西藏标本重新描述林氏下盾螨Hypoaspis linteyini Samsinak,1964雌螨.

根据中国标本重新描述羽美绥螨Ameroseius plumosus Oudemans,1902雌螨。

The predacious mite Neoseiulus cucumeris (Oudemans) is an effective natural enemy of pest insects and mites. To identify the relative fitness of the avermectin-resistant strain of N. cucumeris, the life history parameters of avermectin resistant (R) and susceptible (S) strains of N. cucumeris were observed under experimental conditions (25 ± 1°C, 90 ± 5% RH and L: D = 14:10 h) feeding upon Tetranychus truncatus (Ehara). Fertility, net reproductive rates (R0 /female), intrinsic rates of increase (r/day) and development durations of the two strains were compared. The abamectin resistant strain of N. cucumeris had significantly shorter developmental duration and longevity than the sensitive stain. However, the mean fecundity of the resistant strain was significantly higher than that of the susceptible strain. The net reproductive rate (R0=30.3833 offspring), the intrinsic rate of increase (r=0.2231 d-1) and the finite rate of increase (λ=1.2499 d-1) of the resistant strain were only slightly higher than those of the susceptible strain (R0=29.5333 offspring, r=0.2130 d-1, λ=1.2373 d-1); the differences were not significant. However, the mean generation time (T=15.1768 d) of the resistant strain was significantly shorter than that of the susceptible strain (T=16.0314 d).

The genus Stigmaeopsis (family Tetranychidae) has 11 species including the serious bamboo pest, S. nanjingensis. All Stigmaeopsis species are difficult to identify by their morphology, and the diagnostic character (the length of dorsal setae) can be used only to identify fresh specimens. To identify these species at the molecular level, we sequenced the cytochrome c oxidase subunit I (COI) gene of mitochondrial DNA and two nuclear ribosomal RNA genes (18S and 28S) of 20 strains of seven species of Stigmaeopsis [S. celarius, S. longus, S. miscanthi (both low-and high-aggression phenotypes), S. nanjingensis, S. tenuinidus, S. saharai and S. takahashii]. In maximum likelihood (ML) phylogenetic trees of both COI and combined 18S-28S genes, all but one Stigmaeopsis species could be identified as a monophyletic clade with high bootstrap values. The present results strongly suggested that the exceptional species, S. miscanthi, consists of three biologically different entities based on two phylogenetic trees. Though the phylogenetic trees did not comprehensively solve the phylogeny of Stigmaeopsis, a phylogenetic tree based on the combined nuclear genes showed a sibling relationship between two sub-social Stigmaeopsis species, S. miscanthi and S. longus. In addition, diagnostic PCR detected Wolbachia or Cardinium, which frequently affect mitochondrial haplotypes, in S. longus and S. nanjingensis. In the COI tree, S. longus was separated into two groups which were more consistent with their bacterial infection status than with their geographical distribution.

1. A type of arms race that includes predation, counterattacks and cross‐counterattacks occurs between the phytophagous mite Stigmaeopsis nanjingensis (Ma et Yuan), which lives in self‐woven nests and exhibits cooperative sociality, and its specialised phytoseiid mite predator, Typhlodromus bambusae Ehara.2. First, the efficiency of the S. nanjingensis (prey) counterattacking T. bambusae (predator) was observed. The prey females frequently locked the immature predators out of their nests using silk web, and the predators subsequently died of starvation. Furthermore, the prey males often killed immature T. bambusae mites after they invaded the nests.3. This reversal of roles in the predator–prey system was then re‐reversed (returned to a normal state) by the behaviour of T. bambusae females. Immature predators could maintain their predacious natures due to the presence of attending adult females, which are able to cope with the prey counterattack behaviours.

Four selective pesticides (chlorantraniliprole, flubendiamide, spirotetramat, metaflumizone) and a conventional pesticide (abamectin) were tested against Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae), which is often used as a biological control agent. Abamectin caused high mortality (88.75-92.50%) in N. cucumeris adult females, while the other pesticides had a reduced effect. Chlorantraniliprole was found to have a clear repellent activity against N. cucumeris adult females. Flubendiamide, spirotetramat, and metaflumizone had significant impacts on the development and predation of immature mites; spirotetramat had the greatest effect. The four selective pesticides significantly reduced prey consumption and the number of eggs produced by gravid females. Overall, chlorantraniliprole was categorized as harmless to N. cucumeris, flubendiamide and metaflumizone showed an intermediate effect, and spirotetramat had a significant sublethal effect. Our findings showed that chlorantraniliprole could be used in fields with N. cucumeris, whereas flubendiamide and metaflumizone had poor compatibility with this predatory mite. It would be counterproductive to combine the use of this biological control agent with spirotetramat.

There were 28 species of gamasid mite from Wuyi Natural Reserve in 2007.Among them,9 species are new records to Fujian.They are as following:Pellonyssus nidi Gu et Duan 1991,Ameroseius furcatus Karg 1971,Gamasellus montanus Willmann 1936,Gamasellus tianmuensis Liang et Ishikawa 1989,Gamasellodes changjiangensis Ma 2008,Asca anwenjui Ma 2003,A.hainanensis Ma et Lin 2008,A.yunnanensis Ma et Lin 2008 and Gamasholaspis duyunensis Chen,Guo et Gu 1994.

Nesting behavior is considered to be an important element of social living in animals. The spider mites belonging to the genus Stigmaeopsis spend their lives within nests produced from silk threads. Several of these species show cooperative sociality, while the others are subsocial. In order to identify the origins of this social behavior, comparisons of nest sizes, nesting behaviors (making nests continuously or separately), and their associated traits (fecal deposition patterns) were made for eight cogeneric Stigmaeopsis species showing various levels of social development. All of these species inhabit bamboo plants (Poaceae). We initially addressed the proximate factor of nest size variation. The variation in nest size of the eight species corresponded well with the variation in dorsal seta sc1 length, suggesting that nest size variation among species may have a genetic basis. The time spent within a nest (nest duration) increased with nest size on the respective host plants. Nest arrangement patterns varied among species showing different sized nests: Large nest builders continuously extended their nests, while middle and small nest-building species built new separate nests, which resulted in different social interaction times among species, and is thought to be closely related to social development. Fecal deposition behaviors also varied among Stigmaeopsis species, suggesting diversity in anti-predatory adaptations. Finally, we discuss how the variation in sociality observed within this genus is likely the result of nest size variation that initially evolved as anti-predator strategies.

Abstract The effect of competition on species that coexist with similar ecological niches is an important theme in ecology. Furthermore, species displacement by introduced or invaded species is also an important environmental problem for biological control and conservation ecology. We tested whether two species of phytoseiids could coexist in closed cages with ample quantities of the extraguild prey species Carpoglyphus lactis (L.). Three species of phytoseiid mites—Amblyseius eharai Amitai & Swirski (a species native to China), Amblyseius swirskii (Athias-Henriot) and Neoseiulus cucumeris (Oudemans) (both species were introduced from outside of China)—were tested under experimental conditions (25 ± 1° C, 90 ± 5% relative humidity, and a photoperiod of 14: 10 [L: D] h). With extraguild prey, we found that the numbers of a single population of each phytoseiid species (initial density of 10 females per cage) reached a plateau between 18 and 25 d after introduction into the experimental cages, suggesting that density-dependent factors were operating. In closed environments, one of these density-dependent factors might be cannibalism by these species. With regression analyses, Lotka–Volterra equations estimated the rate of population increase (r) and the carrying capacity (K) of each species with the data from observations on population dynamics. We next observed the interactions of two phytoseiid species with abundant extraguild prey. In all species combinations, one species went extinct and the other increased in population size, despite the availability of sufficient extraguild prey, suggesting some type of competition must have caused the extinctions. We suggested that intraguild predation is the most plausible hypothesis to explain the results.

Two new species-Stigmaeopsis temporalis n. sp. collected in Kochi, Japan, and S. tegmentalis n. sp. collected in Fuzhou, China-both from bamboo plants, are described. In addition, four new life types (WN-p, WN-h, WN-n, and CW-g) in five species-S. temporalis, Stigmaeopsis tenuinidus Zhang et Zhang, S. tegmentalis, Neonidulus tereotus Beard et Walter, and Eotetranychus asiaticus Ehara-are documented in relation to their supposed functions.