多次释放胡瓜新小绥螨对橘园节肢动物群落多样性的影响

为了探明长期多次释放胡瓜新小绥螨(Neoseiulus(Amblyseius)cucumeris)是否会对橘园节肢动物群落的生物多样性产生影响,我们在福州马尾和晋安试验区的2个橘园分别设置生防园、自然园和化防园,连续两年每月两次在各处理橘园的树冠和地面杂草中采集并记录节肢动物的种类和数量,结果表明两个试验区的物种丰富度(S)均以生防园最高,且都显著高于相应的化防园和自然园;马尾试验区三种处理的多样性指数(H’)和均匀度指数(E)的大小依次为生防园>自然园>化防园,晋安试验区则为自然园>生防园>化防园,表明释放胡瓜新小绥螨防治柑橘害螨,减少农药的使用,能恢复或增加橘园节肢动物群落的生物多样性。此外,释放胡瓜新小绥螨未对橘园原有的捕食螨类群产生影响。     

山楂叶螨对胡瓜钝绥螨的吸引作用研究

采用两侧吸引作用试验测定天敌胡瓜钝绥螨Amblyseius cucumeris Oudemans在田间对山楂叶螨的搜索和控制能力。结果表明：山楂叶螨不同螨态对胡瓜钝绥螨均有显著的吸引作用,排泄物对胡瓜钝绥螨没有明显的吸引作用。山楂叶螨对胡瓜钝绥螨的这种吸引作用说明胡瓜钝绥螨在田间具有自动搜索山楂叶螨的能力,可用于山楂叶螨的生物防治。     

从捕食者、猎物的生物学分析胡瓜新小绥螨对针叶小爪螨的控制作用

【目的】为了研究胡瓜新小绥螨Neoseiulus cucumeris(Oudemans)对针叶小爪螨Oligonychus ununguis(Jacobi)的控制能力,为大田防治提供依据。【方法】应用胡瓜新小绥螨和针叶小爪螨的生物学与实验种群生命表的数据进行比较分析。【结果】研究表明:1在(20±1)~(32±1)℃温度条件下,取食针叶小爪螨的胡瓜新小绥螨幼螨、若螨、成螨均能正常生长和繁殖,发育历期随着温度升高而缩短;2在(20±1)、(25±1)、(30±1)、(32±1)℃温度条件下,以针叶小爪螨为食物的胡瓜新小绥螨的产卵量分别为(37.8±5.15)、(52.9±1.92)、(49.5±6.50)、(42.0±6.34)粒,而在同等温度条件下,取食板栗叶片的针叶小爪螨的产卵量分别高出胡瓜新小绥螨的141%、169%、194%和149%;3在(20±1)、(25±1)、(30±1)和(32±1)℃温度条件下,针叶小爪螨的净增殖率(R0)分别为36.5453、66.9788、66.2848、45.4846,比胡瓜新小绥螨高出72.88%、118.36%、92.12%、93.55%,说明针叶小爪螨的生殖潜能与产雌率高于胡瓜新小绥螨,而胡瓜新小绥螨每一世代周期(T)为29.6337、24.2193、20.2165、22.2009d,分别短于针叶小爪螨46.75%、42.03%、39.13%、29.63%;4在(20±1)、(25±1)、(30±1)℃温度条件下,胡瓜新小绥螨的内禀增长率(rm)为0.1030、0.1413、0.1699,分别高于针叶小爪螨的127%、105%、106%,而在(32±1)℃条件下针叶小爪螨的内禀增长率(rm=0.1636)高于胡瓜新小绥螨的115%,说明高温有利于针叶小爪螨的种群增长。【结论】在针叶小爪螨初发生期释放胡瓜新小绥螨能有效地控制其种群增长。     

截形叶螨对胡瓜钝绥螨的吸引作用

室内测定表明,截形叶螨不同螨态对胡瓜钝绥螨均有显著的吸引作用,均达到极显著水平,而胡瓜钝绥螨对截形叶螨的排泄物没有明显的反应。截形叶螨对胡瓜钝绥螨的这种吸引作用说明胡瓜钝绥螨具有自动搜索截形叶螨的能力,表明胡瓜钝绥螨可以用于截形叶螨的生物防治。     

胡瓜新小绥螨和尼氏真绥螨生物学特性比较研究

胡瓜新小绥螨Neoseiulus cucumeris和尼氏真绥螨Euseius nicholsi是重要的捕食性天敌,其中前者为引进种类,后者为本地种类。本文在室内25℃条件下,以粉螨为食料饲养胡瓜新小绥螨,以二斑叶螨为食料饲养尼氏真绥螨,组建生殖率表,结果表明：胡瓜新小绥螨的产卵量（平均36.35±5.56粒/雌）、內禀增长率（rm=0.0942）、周限增长率（λ=1.0988）均高于尼氏真绥螨的平均产卵量29.78±3.11粒/雌、内禀增长率rm=0.0827、周限增长率λ=1.0863,且种群倍增时间（t=7.35 d）也较尼氏真绥螨（t=8.38 d）短。通过各参数的比较,在恒温25℃条件下,胡瓜新小绥螨具有较大的生殖潜力。在以桔全爪螨为食料,进行混合饲养时,两种捕食螨的种群增长均受到抑制,而尼氏真绥螨受到的抑制更明显。说明胡瓜新小绥螨竞争力强于尼氏真绥螨。     

胡瓜钝绥螨对日光大棚茄子上烟粉虱的控制作用

为了评价胡瓜钝绥螨在我国日光大棚中对茄子上烟粉虱虱的控制作用。笔者研究了在24～34℃下胡瓜钝绥螨以烟粉为猎物时的发育历期,并在我国山东省寿光市的蔬菜基地上开展了利用胡瓜钝绥螨控制日光大棚茄子上烟粉虱的研究与应用。结果表明:胡瓜钝绥螨能够取食烟粉虱的卵、成虫、若虫及伪蛹;利用胡瓜钝绥螨能有效地控制烟粉虱成虫、卵、若虫种群数量的增长。根据胡瓜钝绥螨和烟粉虱的生物学特性,结合大棚茄子栽培过程中的环境条件,笔者提出了在日光大棚中应用胡瓜钝绥螨控制茄子上烟粉虱的策略:(1)在茄子的整个生长季节(250d)中需释放胡瓜钝绥螨4～6次,苗期每次每株释放5～10头,结果期每次每株释放20～40头;(2)释放胡瓜钝绥螨的生防区比常规化防区减少农药使用18次;(3)安装防虫网、适时释放胡瓜钝绥螨是生防成功之关键,生防区配合使用黄板效果更好。     

引种捕食螨胡瓜新小绥螨在中国的适生区分布预测

胡瓜新小绥螨(Neoseiulus cucumeris)是一种商业化的广食性生防天敌,可以防治多种农业害螨和害虫,具有重要的经济和生态价值。但是作为一种外来引种的捕食螨,它在我国的适生区域分布以及气候变化对其分布的影响尚不明确。根据胡瓜新小绥螨的现有分布点和19个生物气候因子,利用刀切法评估关键气候因素的重要性,并采用Maxent生态位模型分别预测了目前和未来气候条件下它在中国分布情况,分析了其在中国的潜在适生区域的变化。结果表明模型预测得到的受试者工作特征曲线ROC曲线下的面积AUC(Area under curve)值为0.87,表明模型的准确度好。最冷季节的降水量(Bio＿19)、等温性(Bio＿3)和气温季节性(Bio＿4)是影响胡瓜新小绥螨适生性的最重要的环境因子,对模型的贡献率分别为36.2%、25%和18.1%。目前胡瓜新小绥螨的适生区面积约占我国陆地面积的60%,在未来气候条件下,其适生区域有进一步扩大的趋势,在2050年其中高度适生区域扩张至63%。不同时期胡瓜新小绥螨的分布中心比较稳定,均分布于四川省内,但有向东北迁移的趋势。本研究明确了胡瓜新小绥螨在中国适宜的释放区域及可能定殖的区域,为该引种天敌的合理利用提供了理论依据。     

土耳其斯坦叶螨对胡瓜钝绥螨的吸引反应

土耳其斯坦叶螨（Tetranychus turkestani Ugarov ＆ Nikolski）对胡瓜钝绥螨（Amblyseius cucumeris Oudemans）的吸引测试表明,胡瓜钝绥螨对不同螨态的土耳其斯坦叶螨的刺激均能产生显著的吸引反应。胡瓜钝绥螨能捕食土耳其斯坦叶螨的卵,但对土耳其斯坦叶螨的“卵＋丝网＋粪便＋取食斑”没有明显的反应,土耳其斯坦叶螨的若螨I和幼螨是胡瓜钝绥螨最喜欢的猎物。土耳其斯坦叶螨主要通过活动螨对胡瓜钝绥螨产生吸引反应,这种吸引反应能明显提高胡瓜钝绥螨在田间搜索土耳其斯坦叶螨的能力。     

矿物油乳剂与巴氏新小绥螨对柑橘全爪螨的协同控制研究

利用捕食螨防治柑橘全爪螨Panonychus citri已有大面积应用,但捕食螨田间防治效果常受到果园使用化学农药的影响,相应配套技术是捕食螨应用的瓶颈问题。2010年6～10月,在广东省四会市罗源镇柑橘园,分别采用五种处理方式(常规化学农药;化学农药加巴氏新小绥螨Neoseiulus barkeri;单独使用矿物油乳剂;单独使用巴氏新小绥螨;矿物油乳剂加巴氏新小绥螨)防治柑橘全爪螨,设不采取任何防治措施的样地为对照。试验结果显示,各处理的种群干扰控制指数分别是3.7195、1.4942、0.2439、0.2053、0.0488,校正虫口减退率分别是-271.95%、-49.42%、75.61%、79.47%、95.12%。化学农药防治对柑橘全爪螨的控制作用不理想,影响了巴氏新小绥螨的持续控制作用;巴氏新小绥螨能较好地发挥对柑橘全爪螨的控制作用,矿物油乳剂表现出较好的长期控制效果,矿物油乳剂配合巴氏新小绥螨对柑橘全爪螨有较好的协同控制作用。     

受害前后的九里香嫩梢对柑橘木虱的吸引作用及其挥发物成分分析

柑橘木虱Diaphorina citriKuwayama是黄龙病的传播媒介,九里香Murraya paniculateL.是柑橘木虱最重要的寄主植物。本研究比较了受柑橘木虱为害前后的九里香对其趋性的影响,并在此基础上,分析受害前后的九里香嫩梢挥发物组成成分。结果表明,与未受为害的九里香相比,受为害后的九里香对柑橘木虱的吸引作用显著增强,而且受害后继续保留柑橘木虱的九里香吸引作用更强。受木虱为害前后九里香挥发物成分差异较大,相同组分含量差异也比较明显。仅存在于受为害后的九里香挥发物共有8种,分别为γ-橄榄烯、α-愈创木烯、Epi-β-檀香烯、顺式-β-金合欢烯、(+)-香橙烯、α-菖蒲二烯、十四甲基环七硅氧烷、α-绿叶烯;而仅存在于未受为害的九里香挥发物为6种,为别为孕烯醇酮、β-榄香烯、2,6-二叔丁基苯醌、异丙茴香醚、1-(1,5-二甲基己基)-4-甲基苯、α-柏木烯。这些差异物质可能在柑橘木虱的寄主定位中起着重要作用。     

双尾新小绥螨的形态特征及捕食性功能

【目的】通过对新疆本地捕食螨双尾新小绥螨Neoseiulus bicaudus Wainstein的形态学特征观察及其对新疆农作物上两种重要害螨的捕食量测定,为该捕食螨的保护、研究、扩繁和释放提供理论基础。【方法】在实验室(26±1)℃,RH60%,16L︰8D条件下,借助显微成像系统观察其各个螨态形态特征及生物学习性;定量小室饲养技术对不同密度下对新疆两种重要害螨各螨态的捕食量进行研究。【结果】双尾新小绥螨有卵、幼螨、第一若螨、第二若螨和成螨5个螨态,嗜好阴暗条件,活动范围小,通过有性生殖进行繁殖,有多次交配行为,产卵方式为单产;单头双尾新小绥螨雌成螨每日对截形叶螨Tetranychus truncatus卵和幼螨的捕食量(106.8粒/日·雌和45.4头/日·雌)要显著大于土耳其斯坦叶螨Tetranychus turkestani(64.4粒/日·雌和39.4头/日·雌),而对两种叶螨的若螨和成螨捕食量无明显差异。【结论】本研究表明双尾新小绥螨对土耳其斯坦叶螨和截形叶螨的卵和幼螨的捕食较对若螨和成螨的效果好,对新疆害螨有一定控制能力。     

Rearing of coconut mite Aceria guerreronis and the predatory mite Neoseiulus baraki in the laboratory

A method was developed for the rearing of coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae), and its predatory mite Neoseiulus baraki (Athias-Henriot) (Acari: Phytoseiidae) on embryo culture seedlings of coconut (Cocos nucifera) in the laboratory. Seedlings in the ages of <2, 2–4 and 4–6 months were infested with 75 field-collected coconut mites and the population growth was determined up to six weeks after introduction. The populations of coconut mites increased exponentially up to five weeks after introduction and declined thereafter on seedlings of all ages with significant differences among the three groups of seedlings occurring over time. At week 5, a significantly higher mean number (±SE) of coconut mites (20,098 ± 3,465) was bred on 4–6-month-old seedlings than on smaller seedlings, and on the largest seedlings the numbers were highest at all time intervals, except at week 2. Neoseiulus baraki was reared on embryo culture seedlings of the three age groups infested with coconut mites, by introduction of five female deutonymphs and one male, three weeks after introducing coconut mites. Predator numbers progressed significantly over time, but the size of seedlings did not significantly influence the numbers. On all groups of seedlings, the mean number of N. baraki increased up to two weeks after introduction on to seedlings and then declined. Many coconut mites were successfully reared in the laboratory for a longer period by this method and it could also be used as an alternative method to rear N. baraki. Development of this method may contribute to the progress of studies on the biology and ecology of coconut mite and its interactions with natural enemies.     

Rapid cold hardening response in the predatory mite Neoseiulus californicus

We investigated the rapid cold hardening (RCH) response in the predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae). On direct exposure, ≤2 % of adult females survived ?10 °C for 2 h. However, when acclimatized first at 5 °C for 1 h, 75 % of females survived. RCH could also be induced by acclimatization at 30 °C for 2 h or anoxia (oxygen-free nitrogen) for 1–2 h. All immature stages showed enhanced survival when acclimatized at 5 °C for 2 h before exposure to ?10 °C. Acclimatization at 30 °C induced RCH only in eggs and deutonymphs, and anoxia was effective for eggs, larvae, and deutonymphs. The variability among immature stages may be attributed to the cost associated with the acclimatization treatments. Our findings suggest that RCH may promote the survival of N. californicus during unexpected changes in temperatures, and can be an important feature particularly when this natural enemy is introduced to non-native environments.     

巴氏新小绥螨对猎物搜寻能力的研究

巴氏新小绥螨Neoseiulus barkeri(Hughes)是一种多食性捕食螨,主要捕食叶螨和蓟马等。因其捕食范围广,捕食量相对较大,且易人工繁殖,因此,被广泛应用于农业生物防治中。本文利用温室的释放-回收实验研究了巴氏新小绥螨对截形叶螨Tetranychus truncatus和西花蓟马Frankliniella occidentalis(Pergande)的搜寻能力。实验共设3个处理:(1)叶螨为害植株与清洁植株;(2)蓟马虫害植株与清洁植株;(3)蓟马、叶螨混合为害植株与清洁植株。当捕食螨释放于清洁黄瓜植株和虫(螨)害黄瓜植株交替排列的六角结构的中心时,2种害虫(螨)不论是单独危害还是混合危害,巴氏新小绥螨回收比例随着时间的延长逐渐趋于平缓。释放后1 d之内,叶螨、蓟马及混合猎物处理中回收到的捕食螨分别占释放总量的65.25%±1.61%、62.75%±1.31%和81.75%±2.14%,并且虫(螨)害植株上回收到的捕食螨数量明显比清洁植株多,叶螨、蓟马及混合猎物危害植株回收的捕食螨量分别占释放总量的53.5%±5.6%、49.5%±3.6%和74.0%±2.7%。因此,巴氏新小绥螨对这2种猎物及其混合物均有较强的搜寻能力,能够有效定位作物中有猎物的植株。同时对利用一种捕食螨生物防治温室中同时发生的2种害虫(螨)的可能性进行了讨论。     

Effects of thermal stress on lipid peroxidation and antioxidant enzyme activities of the predatory mite,Neoseiulus cucumeris (Acari: Phytoseiidae)

Changes in temperature are known to cause a variety of physiological stress responses in insects and mites. Thermal stress responses are usually associated with the increased generation of reactive oxygen species (ROS), resulting in oxidative damage. In this study, we examined the time-related effect (durations for 1, 2, 3, and 5 h) of thermal stress conditions—i.e., relatively low (0, 5, 10, and 15 °C) or high (35, 38, 41, and 44 °C) temperatures—on the activities of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), peroxidase (POX), glutathione S-transferases (GSTs), and total antioxidant capacity (T-AOC) of the predatory mite Neoseiulus cucumeris. Also the lipid peroxidation (LPO) levels of the predatory mite were measured under thermal stress conditions. The results confirmed that thermal stress results in a condition of so-called oxidative stress and the four antioxidant enzymes play an important role in combating the accumulation of ROS in N. cucumeris. CAT and POX activity changed significantly when the mites were exposed to cold and heat shock, respectively. The elevated levels of SOD and GSTs activity, expressed in a time-dependent manner, may have an important role in the process of antioxidant response to thermal stress. However, the levels of LPO in N. cucumeris were high, serving as an important signal that these antioxidant enzyme-based defense mechanisms were not always adequate to counteract the surplus ROS. Thus, we hypothesize that thermal stress, especially extreme temperatures, may contribute much to the generation of ROS in N. cucumeris, and eventually to its death.     

Prey preference of the predatory mite Neoseiulus womersleyi Schicha is determined by spider mite webs

Abstract:  We experimentally verified a proximate cause for the preference of prey species by the predatory mite Neoseiulus womersleyi , which prefers the eggs of Amphitetranychus viennensis Zacher to those of Tetranychus urticae Koch. To separate the effects of spider mite eggs and spider mite webs on the prey preference of the predatory mite, we manipulated combinations of eggs and webs of the two prey species. The number of eggs consumed by adult female N. womersleyi was compared with respect to two factors: eggs of the same species under webs of the different species and eggs of different species under webs of the same species. The results revealed that the prey preference of N. womersleyi was determined by the webs, and not by the eggs.