Mathematical Model for Two-Spotted Spider Mites System: Verification and Validation

This paper presents and compares four mathematical models with unique spatial effects for a prey-predator system, with Tetranychus urticae as prey and Phytoseiulus persimilis as predator. Tetranychus urticae, also known as two-spotted spider mite, is a harmful plant-feeding pest that causes damage to over 300 species of plants. Its predator, Phytoseiulus persimilis, a mite in the Family Phytoseiidae, effectively controls spider mite populations. In this study, we compared four mathematical models using a numerical simulation. These models include two known models: self-diffusion, and cross-diffusion, and two new models: chemotaxis effect model, and integro diffusion model, all with a Beddington-De Angelis functional response. The modeling results were validated by fitting experimental data. Results demonstrate that interaction scheme plays an important role in the prey-predator system and that the cross-diffusion model fits the real system best. The main contribution of this paper is in the two new models developed, as well as the validation of all the models using experimental data.

Efficacy of Metarhizium anisopliae in controlling the two-spotted spider mite Tetranychus urticae on common bean in screenhouse and field experiments

The efficacy of aqueous and emulsifiable formulations of the fungus Metarhizium anisopliae isolate ICIPE78 was evaluated on the population density of Tetranychus urticae infesting common bean plants under screenhouse and field conditions. Synthetic acaricide abamectin was included as a check. Bean plants were artificially infested with T. urticae and allowed to multiply. Three treatments were applied in the screenhouse and 1 treatment in field trials. Mite density was recorded 2 d before spraying and weekly postspraying. The number of pods per plant, number of seeds per pod, and the dry weight of seeds per plant were recorded only in the screenhouse trials. In both screenhouse and field trials, fungal formulations applied at the concentration of 108 conidia/mL and the aearicide reduced the population density of mites as compared to the controls. There were signif- icant differences in T. urticae population densities between the treatments at the various post-spraying sampling dates. In the screenhouse, the mite densities were near zero from 3-week postspraying in the treated leaves. At 4-week postspraying, there were no more leaves in the untreated control （T1） and in the control water ＋ Silwet-L77 （T2）. Fungal formulations were as effective as abamectin in reducing mite densities in both screenhouse and field experiments. There were significant differences in the production parameters during the 2 screenhouse trials, with fungal and abamectin treatments generally having the highest yield. Results of this study underline the potential of the M. anisopliae isolate ICIPE78 as an alternative to acaricides for T. urticae management.

黄花菜主要虫害的发生与防治

通过查询文献资料,结合2021—2023年大同市云州区黄花菜主产区害虫发生动态和防治策略调研结果,分析总结了黄花菜主要害虫蓟马、蚜虫和叶螨的发生规律、为害特点和防控策略,着重推荐了黄花菜生产中针对这3种害虫采用的物理防控措施、生物防治策略及化学防治农药,以期为黄花菜的科学防控提供参考。

Lack of fitness cost and inheritance of resistance to abamectin based on the establishment of a near-isogenic strain of Tetranychus urticae

Many populations of the two-spotted spider mite, Tetranychus urticae Koch, have developed high levels of resistance to the pesticide abamectin in China and other countries. This study developed a near-isogenic line to understand better the inheritance, cross-resistance, and fitness costs associated with abamectin resistance in the field population of T. urticae in China. We introduced the trait that confers extremely high abamectin resistance in a field-collected population of T. urticae into a susceptible laboratory strain(IPP-SS) to generate an abamectin-resistant near-isogenic line(NIL-Aba).This process was carried out through multiple backcrossing to IPP-SS and via parthenogenesis and abamectin screening. Compared with IPP-SS, the NIL-Aba strain had a 25 147-fold resistance to abamectin and a high level of cross-resistance to bifenthrin(288.17-fold), an intermediate level to emamectin benzoate(42.57-fold), and low levels to bifenazate, chlorfenapyr, cyflumetofen, cyenopyrafen, and cyetpyrafen with resistance ranging from 3.18-to 9.31-fold.But it had no cross-resistance to profenofos. The resistance to abamectin in NIL-Aba was autosomal, incompletely dominant, and polygenic. Based on two sex life table parameters, no fitness cost was found in NIL-Aba. Establishing the NIL-Aba strain provides a reliable basis for an in-depth study of abamectin resistance in T. urticae. New information on toxicological characteristics and fitness cost should facilitate the management of abamectin resistance in field populations of T. urticae.

基于迁移学习和改进残差网络的棉花叶螨为害等级识别

针对人工诊断棉叶螨害分级准确率低、耗时长、成本高的问题,提出一种基于迁移学习和改进残差网络的棉花叶螨为害等级识别方法。以3种受害等级的棉花叶片与健康叶片图像作为对象,分别于单一背景和自然环境下采集图像,构建图像数据集。首先,利用PlantVillage数据集预训练模型,使用数据增强技术对数据集进行数据增强,扩充训练样本;然后,在ResNet50网络模型的基础上,引入焦点损失函数,在不同网络层嵌入注意力机制模块,并加入Dropout正则化构建改进的ResNet50模型;最后,对比不同模型的识别效果。结果表明:同时在深层和浅层引入注意力机制模块,设定动量为0.9、学习率为0.001时,改进的ResNet50模型具有最好的分类效果,优于ResNet50、VGG16、MobileNet、AlexNet和SENet模型,对棉叶螨危害等级的平均识别准确率达到97.8%。

Rop plays conserved roles in the reproductive and digestive processes of spider mites

Ras opposite(Rop)is known to play an essential role in regulating vesicle trafficking,including synaptic transmission and general secretion.The fundamental roles of Rop have been confirmed by the observation that null mutations in many organisms generate lethal phenotypes during embryogenesis.However,the effects of Rop during the postembryonic stages,especially in non-model organisms,remain largely unknown.Here,we provide new data that enhance our understanding of Rop's roles in the adults of multiple species of Tetranychus spider mites(Acari:Tetranychidae),a class of notorious agricultural pests.Our in silico and experimental evidence demonstrated that Rop is under purifying selection and is highly conserved in Tetranychus spp.RNA interference experiments showed that Rop is required for maintaining normal fecundity but has no significant effect on survival.We further demonstrate that knockdown of Rop darkens the body color of spider mites and blocks the excretion of fecal pellets,which is likely to be related to an abnormality in the excretion of food waste in the digestive system.Overall,our findings clarify novel functions of a vesicle trafficking-related gene in the adult stage of multiple Tetranychus species and highlight the need to evaluate the roles of essential genes in various organisms.

不同寄主植物对二斑叶螨和朱砂叶螨发育历期和产卵量的影响

在室内25℃恒温条件下,分别采用菜豆(Phaseolus vulgarisL inn.)、茄子(Solanum m elongenaL inn.)、月季(Ro-sa chinensisJacq.)、桃树(Amygdalus persicaL inn.)和转B t基因抗虫棉(transgen ic B t cotton)等5种植物饲养二斑叶螨(Tetranychus urticaeKoch)和朱砂叶螨(T.cinnabarinus(Boisduval)),观察它们在这些寄主上的发育情况。结果表明,不同寄主植物上的2种叶螨发育历期及产卵量略有差别,但2种螨都是在桃树上的发育历期最短,在菜豆上的雌成螨5日产卵量均最高。综合发育历期和产卵量两个因素来看,菜豆和桃树为二斑叶螨的最佳寄主;朱砂叶螨在菜豆、茄子和桃树上发育最适合。2种叶螨相比较,适宜的寄主植物略有不同。

捕食螨在我国农林害螨生物防治中的应用

捕食螨是农林生产中极具价值的生防作用物。文章对捕食螨在我国农林害螨生物防治中的应用作一综述,内容包括:与释放应用相关的研究(引进与风险评估,饲养、贮存与运输,食性与释放,捕食与繁殖,定殖与扩散,外界影响因子)、几种主要捕食螨(智利小植绥螨Phytoseiulus persimilis、西方盲走螨Typhlodromus occidentalis、伪钝绥螨Amblyseius fallacis、胡瓜钝绥螨A.cucumeris)的应用、释放应用前景与展望等,旨在提高我国的捕食螨研究与应用水平。

山楂叶螨危害对海棠叶片POD的影响

以人工接种的方法研究了山楂叶螨 TetranychusviennensisZacher 危害初期 9d内 对海棠 Maluszumi 叶片过氧化物酶 POD 的影响.结果表明,随危害时间延长和虫口密度增大,POD活性迅速升高,30头/叶危害9d和60头/叶危害6d时均约达对照的190%;PAGE分析结果显示叶螨危害使海棠叶片产生2种新的POD同工酶,受害植株的未接虫叶片的POD活性同时升高,并出现与接虫叶片相同的PAGE谱带,揭示叶螨危害对海棠叶片POD有系统诱导性.POD的变化可能是受害植株对叶螨危害的一种应激反应.

福建省毛竹叶螨种类危害及分布研究

本文首次报道我省４５个县、市毛竹产区遭受叶螨严重危害、导致大面积毛竹落叶、枯死，给生产及国民经济带来极大损失。经鉴定毛竹叶螨种类共４种：南京裂爪螨ＳｃｈｉｚｏｔｅｔｒａｎｙｃｈｕｓＮａｎｊｉｎｇｅｎｓｉｓＭａｅｔＹｕａｎ、竹缺爪螨ＡｐｏｎｙｃｈｕｓｃｏｒｐｕｚａｅＲｉｍａｎｄ、竹裂爪螨Ｓ．ｂａｍｂｕｓａｅＲｅｃｋ、竹小爪螨ＯｌｉｇｏｎｙｃｈｕｓｕｒａｍａＥｈａｒａ。其中南京裂爪螨、竹裂爪螨、竹小爪螨为福建省新纪录种。本省以南京裂爪螨、竹缺爪螨为优势种，有的区域以单种群存在危害，有的区域以混合种群存在危害。本文对几种叶螨形态、危害状况、分布等作了详细报道。

高温冲击对山楂叶螨的影响

为探索高温冲击对山楂叶螨的影响,在室内采用叶碟饲养的方法,将山楂叶螨不同螨态暴露于33-42℃高温下1-6h,然后在温度(25±1)℃、相对湿度(60±7)%、光周期16h∶8h(L∶D)下测定其寿命、产卵量和孵化率。结果表明,高温冲击对山楂叶螨的影响主要表现在对其产卵量和孵化率的影响,而对成螨的寿命无明显影响;影响的程度取决于高温的强度、持续时间以及处理的螨态。卵经历33-42℃的高温处理1-6h,其孵化率无明显变化,但在随后的发育过程中,幼若螨的发育历期在39℃和42℃6h处理中显著延长,发育至成螨后其产卵量分别增加34.50%和37.41%;幼螨经历39℃和42℃的高温处理6h后发育至成螨时产卵量比对照高出27.02%和35.83%;静止期第二若螨经历39℃和42℃的高温处理,其发育成的雌雄螨的交配和受精能力无明显影响;初羽化雌成螨经历39℃和42℃的高温处理6h后,产卵量不受影响,但卵的孵化率降低了7.01%-11.36%。

京冀地区蔬菜叶螨优势种类鉴定

叶螨是蔬菜作物上的一类重要农业害螨,但其在蔬菜上发生为害的优势种类尚不明确。本研究中,2009-2013年连续5年于北京和河北部分地区定点和非定点采集田间蔬菜作物上的叶螨,采用形态学方法和分子生物学方法进行种类鉴定。结果表明,所采集地的茄果类蔬菜和豆类蔬菜上叶螨种类包括截形叶螨和二斑叶螨,未发现有朱砂叶螨或者其它叶螨种类,表明截形叶螨和二斑叶螨是目前北京和河北部分地区蔬菜作物上的主要叶螨种类,改变了以往文献中朱砂叶螨是常见蔬菜作物主要叶螨种类的传统认识。研究结果将有助于田间蔬菜叶螨的针对性高效防治。

不同寄主植物对山楂叶螨生长发育和繁殖的影响

室内采用叶碟饲养的方法研究了苹果、桃、李、樱桃和杏等不同果树对山楂叶螨Tetrancychusvienensis生长发育和繁殖的影响。结果表明,在李树上山楂叶螨的发育历期短、生殖力强、存活率高,rm值大,而在樱桃和杏树上该螨的发育历期长、生殖力弱、存活率低、rm值小。寄主转换试验结果表明,当山楂叶螨由苹果转移至樱桃和杏树时,其生长发育的历期显著延长,rm值大幅度降低;而由苹果转移至桃树和李树时,其生长发育的历期虽也有所延长,但差异不显著,rm值则明显降低。表明山楂叶螨对新寄主的适应因不同寄主而异,在桃和李上经历1代后即可适应,而在杏和樱桃上经历2代后才能适应新的寄主。

木薯种质对朱砂叶螨的抗性评价

在建立切实可行的木薯抗螨性评级标准的基础上,对国家木薯种质资源圃227份核心木薯种质进行抗朱砂叶螨的抗性评价,并探讨抗、感性稳定的8份木薯种质对朱砂叶螨生长发育与繁殖的影响。结果表明:227份被评价的核心木薯种质中对朱砂叶螨高抗的种质2份,抗性种质4份,中抗种质116份,感性种质87份,高感种质18份;抗性木薯种质对朱砂叶螨的发育与繁殖具有显著的影响,取食高抗种质C1115和缅甸种叶片后朱砂叶螨雌雄成螨均不能存活,与取食高感种质ZM9066、CM1210-10、瑞士F21和BRA900相比,取食抗性种质哥伦比亚4D和PII167后,朱砂叶螨的发育历期显著延长,平均每雌螨产卵量显著减少,后代卵的孵化率显著降低,雌、雄成螨寿命均显著缩短。本研究结果为深入开展木薯抗螨性机理、抗螨种质的挖掘及其利用研究提供了理论基础。

不同灌溉条件下棉叶螨的种群动态

研究了不同灌溉方式(滴灌和沟灌),以及在滴灌条件下,不同灌水量和不同灌水时期处理下,新疆棉花主要害螨——土耳其斯坦叶螨(Tetranychus turkestani)的发生动态。结果表明:不同的灌溉方式和不同灌水量都对棉叶螨的发生有一定的影响;沟灌棉田有利于棉叶螨的发生,滴灌棉田不利于棉叶螨的发生;滴灌条件下,水量过高或过低的棉田均有利于棉叶螨的发生,叶螨发生盛期早于常规水量棉田,数量也高于常规棉田叶螨数。不同灌水时期对棉叶螨的发生影响不大。

骆驼蓬粗提物对植食性螨类的药效试验初报

骆驼蓬（ＰｅｇａｎｕｍｈａｒｍａｌａＬ．）系蒺藜科多年生草本植物，对山楂叶螨（Ｔｅｔｒａｎｙ－ｃｈｕｓｖｉｅｎｎｅｎｓｉｓＺａｃｈｅｒ．）、果苔螨（ＢｒｙｏｂｉａｒａｂｒｉｏｃｕｌａｓＳｃｈｅｕｔｅｎ．）、麦岩螨（ＰｅｔｒｏｂｉａｌａｔｅｎｓＭｕｌｅｒ．）、截形叶螨（ＴｅｔｒａｎｙｃｈｕｓｔｒｕｎｃａｔｕｓＥｈａｒａ．）的室内药效测定发现，其地上部分乙醇提取物对供试的４种植食性螨类具有显著的触杀作用。对山楂叶螨和麦岩螨的田间药效试验结果表明，虫口减退率亦相当高，达到８０％以上。

朱砂叶螨危害初期豇豆幼苗叶片PPO、PAL及POD的研究

对朱砂叶螨(Tetranychuscinnabarinus(Boisduval))危害后豇豆(Vignasinensis)幼苗叶片PPO、PAL和POD活性及同工酶进行了研究.结果显示:随着危害时间延长,处理叶片PPO、PAL和POD的活性与对照相比均升高,差异显著,且两处理之间也存在显著差异;POD同工酶电泳结果显示,随着危害程度的增大,除了部分同工酶谱带加强外,还诱导产生了新的同工酶谱带.

茄子叶螨种群消长动态及阿维菌素防治研究

连续2年调查了北京地区春茬塑料棚和露地茄子叶螨的种群消长动态,并评价了施用阿维菌素对棚内叶螨的防治效果。结果表明,北京地区春茬塑料棚内茄子叶螨的种群消长有明显的初现、上升、高峰和下降阶段,而露地叶螨的种群动态则随着气象条件的变化呈现明显波动趋势;露地和塑料棚内茄子叶螨均于5月底初现,6月上旬种群数量开始上升,此时是预防的最佳时机。1.8%阿维菌素乳油稀释2 500倍于种群高峰期前对棚内茄子植株进行均匀喷雾,药后7 d和14 d对叶螨的防效分别达84.11%和97.67%,表明喷施阿维菌素对茄子叶螨具有良好的控制作用,同时对蓟马和粉虱类害虫也有一定的兼治效果。

国槐行道树叶螨种群消长与环境因子的分析

通过两年的系统调查及数据资料分析 ,明确了国槐行道树叶螨的种群消长与环境因子有着密切的关系 :高温干燥的气候是叶螨猖獗为害的决定因子 ;持续 2 5℃以上的日均温度和 70 %以下的空气湿度是叶螨种群急剧上升的最适条件 ;连阴雨及其产生的高湿天气对叶螨种群有明显的抑制作用 ,而大雨、暴雨、冰雹和急剧降温天气对叶螨有显著的冲刷和杀伤作用 ;

叶螨危害对豇豆叶片超氧化物歧化酶及过氧化氢酶活性的影响

对豇豆 (Vignasinensis)幼苗受朱砂叶螨 (TetranychuscinnabarinusBoisduval)危害初期超氧化物歧化酶 (SOD)、过氧化氢酶 (CAT)活性的变化进行了初步研究 .每片叶分别接虫 0 ,2 0 ,4 0头 ,危害 0～ 8d .结果表明 ,在测定期间 ,对照的SOD活性持续降低 ,2d时处理的活性明显上升 ,随后逐渐降低 ,但始终不低于 0d的活性 ,处理与对照间的活性差异显著 ,且随虫口密度增大差异增大 ;在叶螨危害 2d时 ,不同虫口密度处理的CAT活性均较对照升高 ,差异显著 .随危害时间延长 ,CAT活性比对照降低 ,且虫口密度越大降低的幅度越大 .