Molecular phylogeny and identification of agromyzid leafminers in China,with a focus on the worldwide genus Liriomyza(Diptera:Agromyzidae)

Leaf-mining flies(Diptera:Agromyzidae)are a diverse family of small-bodied insects that feed on living plant tissues as larvae.Various species in this family are considered globally invasive and have caused great agricultural economic losses.In China,economically important vegetable crops have been seriously damaged by these pest insects,especially by species of the genus Liriomyza.However,these species are difficult to differentiate because of their morphological similarities,and the Chinese fauna remains poorly known.To explore the relevant pest species in China and their phylogeny,agromyzid leafminers were collected from 2016 to 2019,and identified based on morphological characteristics and DNA barcodes.In total,27 species from five genera of Agromyzidae were sampled and identified,including 16species of Liriomyza.Both mitochondrial and nuclear genes were used to reconstruct their phylogenetic relationships and estimate the divergence time.Highly congruent and well-supported phylogenetic trees were obtained using the Bayesian inference and maximum-likelihood methods.This analysis revealed two main clades in Liriomyza,and clade 2was inferred to have diverged from clade 1 approximately 27.40 million years ago(95%highest posterior density:23.03–31.52 million years ago)in the Oligocene.Differences were observed in the distribution patterns and host associations between the Liriomyza clades.Clade 2 species are distributed in cool,high-latitude environments,suggesting that they may have evolved into a cool-adapted lineage.

Integrated Assessment of Trapping Efficiency of Colored Sticky Cards and Sex Pheromone on Liriomyza spp.and Plutella xylostella

[Objective] To evaluate the control effect of yellow sticky cards and sex pheromone on Plutella xylostella and Liriomyza spp.,which can provide reference for large area extension of the technique.[Method] The integrated assessment of trapping efficiency of colored sticky cards and sex pheromone on Liriomyza spp.and Plutella xylostella was conducted by field surveys and structured interview in Tonghai County,Yunnan Province,China.[Result] The results showed that yellow sticky cards and sex pheromone have strong power of trapping Liriomyza spp.and Plutella xylostella（3 414±720 and（219±157） head/piece,respectively）;the control cost by the usage of pesticide is the highest,（10 099.5±2 752.5） yuan/hm^2,yellow sticky cards and sex pheromone takes the second place,（1 125.0±465.0） yuan/hm^2,the control cost by the usage of yellow sticky cards is the lowest,（450.0 ±186.0）yuan/hm^2.Without the usage of yellow sticky cards and sex pheromone,pesticide application times and costs are（15.0±2.7） times and（12 070.5±2 136.0） yuan/hm^2;combined with usage of yellow sticky cards and sex pheromone,pesticide application times and costs reduce by 5.7 times and 4 618.5 yuan/hm^2.The ratio of trapped beneficial insects and target pests was 1 ∶1 131,which showed that the negative effect of yellow sticky cards and sex pheromone on the non-target insects was very limited.[Conclusion] The trapping approach has become popular among all the local farmers.Looking at the above factors,the trapping technology has strong application prospect and promotion value in pest control field.

Study on Biological Characteristics and Pupa's Cold Tolerance of Liriomyza sativae on Florists cineraria

In this study, Liriomyza sativaes was raised on Florist cinerarias in greenhouse with different temperatures at 15, 20, 25, 30 and 35 ℃, and their corresponding development duration of entire generation were 47.0, 25.0, 15.5, 12.5 and 12.0 d. The beginning growth temperatures of egg, larva, pupa and entire generation of Liriomyza sativae were 8.5, 9.8, 10.2 and 10.4 ℃, and their effective accumulated temperatures were 52.7, 75.8, 158.5 and 262.2 d ·℃, respectively. Liriomyza sativae had 7 generations on Florist cinerarias in Ningxia each year. However, it occurred in the whole year in greenhouse. The length of its development duration in greenhouse decreased in order from cucumber, Callestephus chinensis, Florist cinerarias to pea, but the eclosion rate of its pupa was in the eentrary order. Under the temperature of 10, 0, - 15 and 20 ℃ ,the longer the storage of pupa was,the higher the mortality rate would be. Liriomyza sativae couldn＇t survive in the winter in Ningxia Province in the natural environment.

Genetic Variation of Host Populations of Liriomyza sativae Blanchard

In this study, partial sequences of the mitochondrial cytochrome oxidase subunit I （mtDNA-COI） gene and the ribosomal internal transcribed spacer 1 （rDNA-ITS 1） gene, isolated from five artificial populations of Liriomyza sativae （Diptera： Agromyzidae）, were sequenced and compared, to analyze their genetic variation. Analysis of the mtDNA-CO1 gene showed that a low genetic variation was detected among the five populations and only five variable sites were found in the nucleotide sequences. Most of the observed variations that occurred within the populations were because of nucleotide transitions, whereas, the interpopulation variation was because of the differences in haplotype frequencies occurring among the host populations. Analysis of the rDNA-ITS1 gene revealed a small diversity in the five host populations. The trend of genetic differentiation in the host populations was consistent with the preference of L. sativae to the plant hosts.

Genetic Variations Among Liriomyza sativae Blanchard Populations Indicated by β-tubulin Gene Sequences

To analyze the genetic differentiation of the host- and geo-populations of Liriomyza sativae Blanchard, the β-tubulin gene of 5 host-populations and 6 geo-populations of L. sativae was sequenced. Subsequently, the sequences were analyzed by biosoftware DNAStar and MEGA, and the phylogenetic trees constructed. The results obtained by the two softwares were similar, that is, the sequences of β-tubulin gene were more than 98% homologous, among the host- and geo-populations of L. sativae, with only 8 variable sites, but no insertions and deletions were detected. It seems that differentiations in β-tubulin gene among the host- and geo-populations of L. sativae are related to the hobby to hosts and the geographical distributions, respectively.

Prediction Model Based on BP-ANN and PCA for the Peak Occurrence of Liriomyza Huidobrensis

Liriomyza huidobrensis （Blanchard） is an important vegetable pest of pathology. In order to improve the accuracy of prediction of Liriomyza huidobrensis and to control the Liriomyza huidobrensis effectively, this paper presents a new prediction model by principal components analysis （PCA） and back propagation artificial neural network （BP-ANN） methods. The historical data from 1999 to 2007 on population occurrence are analyzed in order to find out a non-linear relationship between the pest occurrence and the meteorological factors. And then by using analysis results, the prediction model of Liriomyza huidobrensis occurrence in Jianshui in Yunnan is built. The new model has successfully applied to verify the paddy stem borer population occurrence in 2006. Test results show that the new prediction model with BP-ANN and PCA can improve the prediction accuracy.

美洲斑潜蝇Liriomyza sativae幼虫分龄研究

通过对不同寄主植物及寄主植物不同生育时期和不同温度条件下美洲斑潜蝇各龄幼虫头咽骨、口钩和取食道长度的测量,结果表明,按各龄幼虫头咽骨长度可以准确进行美洲斑潜蝇幼虫分龄,而取食道长度不同处理间的差异较大,不宜做为分龄标准。

农药对美洲斑潜蝇Liriomyza sativae的毒力和美洲斑潜蝇抗药性测定

有机磷类农药乐斯本,沙蚕毒素类农药杀虫双和阿维菌素类农药阿巴丁、害极灭、杀虫素对美洲斑潜蝇Liriomyza sativae实验种群成虫和1—2龄幼虫的LC_(50)分别为:成虫48.68,20.97,4.27,1.40和0.63ppm;幼虫70.94,30.42,2.21,2.91和2.08ppm。阿维菌素类农药对美洲斑潜蝇成虫和幼虫均具有较强的毒性.通过比较测定美洲斑潜蝇敏感种群和自然种群幼虫对农药敏感性的差异,得出美洲斑潜蝇对乐斯本的抗性已达到低抗性水平,抗性倍数为9.6倍;而对阿维菌素类农药处于敏感水平.

美洲斑潜蝇Liriomyza sativae(Blanchayd)生物学研究初报

美洲斑潜蝇在温州地区室内饲养１年发生１３～１４代。一般菜区以蛹越冬，冬季大棚栽培的番茄、茄子和暖冬年份蚕豆大田能以幼虫和蛹同时越冬。１１月中旬露地越冬蛹开始进入滞育状态，滞育期长达１１０天左右，越冬主要寄主是蚕豆，尚有少量白菜、莴苣及茄果、瓜类的幼苗。自然条件下，世代重叠明显。初步明确该虫的发育起点温度为７．５３℃（卵、幼虫、蛹的平均值）。

美洲斑潜蝇,Liriomyza sativae应急防治药剂选择的灰靶决策

根据南宁市对美洲斑潜蝇化学防治的田间试验数据，采用灰靶决策分析的方法得出了几种高防效药剂中推广使用综合效益最优的药剂。为大面积推广应用提供了科学依据。

香葱主要虫害防治药剂的筛选

为了筛选防治香葱蓟马、斑潜蝇、斜纹夜蛾的高效安全药剂,通过田间药效试验测定不同杀虫剂对3种害虫的防治效果。结果表明,60 g/L乙基多杀菌素SC对蓟马的防效较好,防效为88.40%~95.93%;60%噻虫·灭蝇胺WG对斑潜蝇的防效较好,防效为81.02%~87.26%;35%氯虫苯甲酰胺WG对斜纹夜蛾的防效较好,防效为88.01%~92.53%,为香葱主要虫害田间防控提供高效药剂。

Functional response of a parasitoid Ganaspidium utilis （Hymenoptera： Eucoilidae） on the leafminer Liriomyza trifolii （Diptera： Agromyzidae）

Functional response of a solitary, larval-pupal endoparasitoid of Liriomyza leafminers, Ganaspidium utilis Beardsley, was estimated on Liriomyza trifolii Burgess at three temperatures （17℃, 25℃, 29℃ ） and host densities. A type Ⅱ random parasitoid equation （RPE） was used to estimate instantaneous search rate and handling time. The instantaneous search rate increased as temperature increased. All of the RPE regressions obtained for functional response of G. utilis at different temperatures were significant （P〈0.01）. The slope of RPE regression lines was lower across the temperatures. At 29±2℃, the maximum number of larvae parasitized was 7.8 per day. It decreased to 7.2 larvae parasitized at 25±2℃. At 17±2℃, no significant increment of parasitization was observed due to the host density increments. The estimated handling time was lowest at 17±2℃ and highest at 25 ± 2℃, respectively. The ability of G. utilis to find and parasitize L. trifolii over a wide range of temperatures makes them a good candidate for biological control of Liriomyza leafminers.

Pea leafminer Liriomyza huidobrensis (Diptera: Agromyzidae) uses vibrational duets for efficient sexual communication

The pea leafminer (Liriomyza huidobrensis) is a notorious pest of vegetables and ornamental plants worldwide. Despite a large number of studies on its biology and ecology, the courtship behavior and sexual communication of this species remain unclear. Here, we studied vibrational communication in the sexual interaction of the pea leafminer. On host plant leaves, females and males behaviorally displayed the bobbing-quivering alternation, which finally led to copulation. Moreover, records of laser vibrometry revealed threesignal duets underlying the behavioral alternation. Sexually mature males spontaneously emitted calls (MCs) to initiate the duets. The females rapidly responded to MCs by emitting replies (FRs) that are longer in duration. The FRs further triggered male replies (MRs) in their search for potential partners. Leafminer-produced vibrational signals convey efficient information to partners and generate pair formation on stretched substrates, such as plant leaves and nylon mesh, but cannot elicit responses on dense substrates, such as glass and plastic. Vibrational playbacks of both MCs and FRs can elicit replies in females and males, respectively. This study completely characterizes substrate-borne vibrational duets in a dipteran insect. The discovery of vibrational sex signals in the pea leafminer provides new insights for the development of novel approaches to control the pest and its relative species.

江苏地区2种入侵性斑潜蝇的发生分布及耐药性

三叶斑潜蝇(Liriomyza trifolii)和美洲斑潜蝇(L.sativae)是我国一类园艺及蔬菜作物上重要外来有害生物,其形态学相似,危害严重。2014和2019年分别对江苏地区2种斑潜蝇的发生分布和危害程度进行调查并对其发生危害的原因进行探讨。结果表明:美洲斑潜蝇主要在苏北地区发生危害并不断向苏南地区扩张,三叶斑潜蝇主要在苏南、苏中地区发生危害,其危害范围逐渐缩小且向北扩张至徐州;2种斑潜蝇主要在豆科植物上进行危害,原先嗜食的茄科作物危害等级整体减弱,而葫芦科作物上原本占优势的三叶斑潜蝇也逐渐被美洲斑潜蝇取代;田间斑潜蝇种群对阿维菌素的敏感性最强,且扬州地区的种群药剂敏感性显著低于苏州和徐州。综上,2019年较2014年2种斑潜蝇在江苏地区发生一定程度的种群动态变化,需要加强监测,并根据近缘种斑潜蝇的发生规律和影响因子进行防治。

Abamectin resistance in strains of vegetable leafminer, Liriomyza sativae （Diptera： Agromyzidae） is linked to elevated glutathione S-transferase activity

Abamectin resistance was selected in the vegetable leafminer, Liriomyza sativae （Blanchard） （Diptera： Agromyzidae） under laboratory conditions, and cross- resistance patterns and possible resistance mechanisms in the abamectin-resistant strains （AL-R, AF-R） were investigated. Compared with the susceptible strain （SS）, strain AL-R displayed 39-fold resistance to abamectin after 20 selection cycles during 25 generations, and strain AF-R exhibited 59-fold resistance to abamectin after 16 selection cycles during 22 generations. No cross-resistance to cyromazine was found in both abamectin-resistant strains. However, we failed to select for cyromazine resistance in L. sativae under laboratory conditions by conducting 17 selection cycles during 22 generations. However, moderate levels of cross-resistance to abamectin （6-9 fold） were observed in strains which received cyromazine treatments. Biochemical analysis showed that glutathione S-transferase （GST） activity in both abamectin-resistant strains （AL-R, AF-R） was significantly higher than in the susceptible strain （SS）, suggesting metabolically driven resistance to abamectinin L. sativae. Recommendations of mixtures or rotation of cyromazine and abamectin should be considered carefully, as consecutive cyromazine treatments may select for low-level cross-resistance to abamectin.

Comparative demography of Liriomyza sativae Blanchard （Diptera： Agromyzidae） on cucumber at seven constant temperatures

Reproduction and population parameters of vegetable leafminer, Liriomyza sativae Blanchard were measured on cucumber （Cucumis sativus L.） at seven constant temperatures （10, 15, 20, 25, 30, 35 and 40℃）. No eggs were found at 10℃ and flies died after exposure to 40℃. The significantly highest intrinsic rate of natural increase （rm）, net reproductive rate （R0） and finite rate of increase （λ） ofL. sativae were obtained at 25℃ as 0.196, 52.452, and 1.216, respectively. The above-mentioned parameters decreased at 15℃ and 135℃ and this reduction at 35℃ was strong. Doubling time （DT） varied significantly with temperature. The shortest doubling time was obtained at 25℃. Mean generation time （T） decreased significantly with increasing temperature between 15℃ and 35℃. Percentage of immature ages in the stable age distribution was more than 95% at all temperatures. Female longevity was greater than male at all temperatures. Liriomyza sativae lived for a long time at 15℃, whereas at 35℃ had lower survival rates. The effect of temperature on reproduction, especially the intrinsic rate of increase of L. sativae would be useful for predicting its longterm population fluctuation over several generations.

番茄潜叶蛾及其他4种番茄常发害虫的高效兼治药剂筛选

番茄潜叶蛾(Phthorimaea absoluta Meyrick)入侵我国后,形成了与美洲斑潜蝇、烟粉虱、蓟马、二斑叶螨4种常发害虫同时危害番茄的态势,对我国番茄的安全生产构成了巨大威胁。为筛选出对番茄潜叶蛾及其他4种害虫的兼治药剂,本研究测定16种常用药剂对番茄潜叶蛾幼虫、美洲斑潜蝇幼虫、烟粉虱成虫、棕榈蓟马成虫、二斑叶螨成螨的毒力效果,综合分析这些药剂的兼治作用。结果表明,对番茄潜叶蛾幼虫具有较高毒力(LC50<5.0 mg a.i./L)的药剂有氯虫苯甲酰胺、阿维菌素、乙基多杀菌素、溴氰虫酰胺、虫螨腈、甲氨基阿维菌素苯甲酸盐(甲维盐)、四唑虫酰胺;对番茄潜叶蛾与美洲斑潜蝇具有高毒力(LC50<18.0 mg a.i./L)的药剂有溴氰虫酰胺、乙基多杀菌素、阿维菌素、虫螨腈、氯虫苯甲酰胺、甲维盐、四唑虫酰胺;对番茄潜叶蛾与烟粉虱高毒力(LC50<28.0 mg a.i./L)的药剂有溴氰虫酰胺、噻虫嗪、阿维菌素、甲维盐;对以上3种害虫具有高毒力(LC50<24.0 mg a.i./L)的药剂主要有溴氰虫酰胺、阿维菌素、甲维盐,这3种药剂同时对蓟马均具有高毒力(LC50<7.0 mg a.i./L)。阿维菌素和甲维盐对5种害虫均具有较高毒力(LC50分别为0.22~9.24、0.80~6.90 mg a.i./L)。番茄生产中可根据番茄潜叶蛾与其他害虫的种类与危害程度,选择相应的兼治药剂,并注意交替使用。

高温对芙新姬小蜂控制美洲斑潜蝇潜力的影响

为明确高温条件对芙新姬小蜂Neochrysocharis formosa(Westwood)成虫寿命以及行为的影响,以美洲斑潜蝇Liriomyza sativae Blanchard 2龄末至3龄初幼虫为寄主,在补充非寄主食物20%葡萄糖溶液的情况下,观察了芙新姬小蜂雌成虫在26、30℃和35℃3个温度下的寿命及对美洲斑潜蝇的取食致死数、叮蛰致死数、寄生致死数和总致死数。结果显示:与26℃相比,高温条件(30℃和35℃)下,单头雌虫的日均取食致死数、日均叮蛰致死数、日均寄生致死数、日均总致死数均显著升高,并在35℃达到最高值,分别为9.6、12.2、5.5头和27.3头。芙新姬小蜂雌成虫的寿命随着温度升高而显著缩短,26℃下的寿命(21.4 d)约为30℃下寿命(11.4 d)的1.9倍和35℃下寿命(9.6 d)的2.2倍。3个温度下雌成虫一生的取食致死数、叮蛰致死数、寄生致死数、总致死数均无显著差异,总寄主致死数均达230头以上。表明35℃高温对芙新姬小蜂控制美洲斑潜蝇的总潜力没有显著影响。

海南首次发现一种新的三叶草斑潜蝇寄生蜂--斑潜蝇亮蝇茧蜂

三叶草斑潜蝇是我国重大入侵害虫之一,主要分布在热带和亚热带地区,可造成巨大的经济损失。寄生蜂作为膜翅目昆虫的一大类群,在害虫生物防治过程中发挥重要作用。据此,笔者于2021年10—12月在海南省各市县开展三叶草斑潜蝇寄生蜂资源普查时发现一种新的三叶草斑潜蝇幼虫寄生蜂。通过形态学鉴定确定该蜂为膜翅目Hyrmenoptera茧蜂科Braconidae蝇茧蜂亚科Opiina亮蝇茧蜂属Phaedrotoma的一个在中国尚未报道的新种,并命名为斑潜蝇亮蝇茧蜂Phaedrotoma sp.2。基于线粒体COI基因的分子进化树结果显示其与亮蝇茧蜂属寄生蜂聚为一类。本研究为后期三叶草斑潜蝇寄生蜂的人工扩繁打下基础,并有助于推动该蜂在田间害虫生物防治中的应用。

南昌地区美洲斑潜蝇及其寄生蜂发生情况的初步分析

7 hymenopterous species have been confirmed by the present study as parasites of Liriomyza sativat in the Nanchang area. These parasites will also porasitize the pea leaf-miner, Phytomyza horticola,except Chrysonotomyia okazakii and Hemiptarsenus varicornis. All of them are larval or larval -pupal purasites and no egg parasite and no egg parasite and pupal parasite has been reared. Opius sp. Diglyphus isaea, Chrysocharis pentheus are the dominant species among the parasites of the Liriomyza sativae as well as the pea leaf-miner in Nanchang area, but there is no effective parasite complex to control Liriomyza sativae as pea leaf miner. The climate and foods are very appropriate to arise the number of Liriomyza sativae in May to Oseptember. According to the investigation in the field, the Liviomyza sativae and its plant of alternative host never find out in winter, in Nanchang area.