Species composition and seasonal-occurrence of spider mites and their predators in sprayed and unsprayed apple orchards in Tokat, Turkey

The species composition and seasonal cycle ofTetranychus urticae Koch (two-spotted spider mite) andEotetranychus uncatus Garman (garman spider mite; the two species were evaluated together),Amphitetranychus viennensis (Zacher) (hawthom red spider nite),Panonychus ulni (Koch) (European red mite),Bryobia rubrioculus (Scheuten) (brown mite) (Acari Tetranychidae),Cenopalpus pulcher Can and Fanz. (flat scarlet mite) (Tenuipalpidae) and their natural enemies (Phytoseiidae and Stigmaeidae family members) were compared in two apple orchards during the years 2000 to 2002 in Tokat, Turkey. One orchard was pesticide-free, and the other was sprayed. Surveys were carried out once a week from April to November and the differences in the dominant species of spider mites and phytoseiid mites between the two orchards were recorded. In the sprayed orchard, the dominant phytophagous mites wereA. vienensis andP. ulmi whereas in the unsprayed orchardE uncatus andC pulcher were abundant. It was found that the predatory mites were able to control spider mites in the unsprayed orchard, but the population level was not adequate to control them in the sprayed orchard, presumably due to the excessive use of pesticides.     

Daily consumption and predation rate of different<Emphasis Type="Italic">Stethorus punctillum</Emphasis> instars feeding on<Emphasis Type="Italic">Tetranychus urticae</Emphasis>

Laboratory experiments were conducted to evaluate the prey stage preference and the daily consumption of each stage of the coccinellid predatorStethorus punctillum Weise (Coleoptera: Coccinellidae) feeding on the two-spotted spider miteTetranychus urticae (Koch) (Acari: Tetranychidae). Groups of different life stages of the prey were offered (eggs, larvae, nymphs and adults). The prey preference varied with the stage ofS. punctillum. First larval instars had no significant preference among theT. urticae stages offered. Second larval instars consumed significantly more spider mite larvae in comparison with nymphs. In contrast, third larval instars indicated a strong preference for mite eggs. Significantly fewerT. urticae larvae were consumed by the fourth larval instars ofS. punctillum, in comparison with the three other mite stages. Finally, adult predators consumed significantly more mite eggs than the other stages offered. This preferential trend was similar for all adults tested, whether during the pre-oviposition or the oviposition period. http://www.phytoparasitica.org posting Feb. 17, 2004.     

Olfactory response of the ladybird beetle <Emphasis Type="Italic">Stethorus gilvifrons</Emphasis> to two preys and herbivore-induced plant volatiles

The spider mites Tetranychus urticae Koch and Panonychus ulmi (Koch) (Tetranychidae) cause severe economic losses to vegetable farms and deciduous fruit orchards in Turkey. One of their predators, the ladybird beetle Stethorus gilvifrons (Muls.) (Col., Coccinellidae), aggregates on mite-infested patches of plants. The present study assessed whether there is a role for herbivore-induced plant volatiles (HIPVs) and/or odors emitted directly from these two mite species in the aggregative response of ladybird beetles. The olfactory responses of the predator females to volatiles from T. urticae- and/or P. ulmi-infested sweet pepper (four cultivars, viz. ‘Demre’, ‘Yalova Carliston’, ‘Kandil Dolma’ and ‘Yag Biberi’), kidney bean (cv. ‘Barbunya’) and apple (M9 rootstock) were investigated using a two-choice olfactometer. Our results showed that HIPVs emitted from both T. urticae- and P. ulmi-infested plants significantly attracted S. gilvifrons adults for all plants except the sweet pepper cv. Yag Biberi. In addition, it was found that volatiles from apple plants infested by T. urticae and, especially, P. ulmi are more attractive for S. gilvifrons females than those emitted by other infested plants. The results also suggest that the odors of T. urticae adults and their products might influence the attraction of S. gilvifrons females.     

Residual toxicity of lambda-cyhalothrin on apple foliage toAmblyseius fallacis and the tarnished plant bug,Lygus lineolaris

The residual toxicity of lambda-cyhalothrin on leaves from a treated apple orchard to a mite predator,Amblyseius fallacis (Garman), in the laboratory, declined to one-third of its original level within 3 weeks. The absence ofA. fallacis on apple trees during the pink bud stage coupled with the results of this study pave the way for the development of integrated pest management strategies where key pre-bloom pests, such as the tarnished plant bug,Lygus lineolaris (Palisot de Beauvois), may be controlled with lambda-cyhalothrin with little if any toxic effects to the predator later in the season. Two years of field testing indicated that 10 g a.i./ha of lambda-cyhalothrin applied at pink was very effective against the tarnished plant bug.     

联肼·乙螨唑对蔬菜优势叶螨产卵发育的影响及其田间防效

为明确新型复配杀螨剂联肼·乙螨唑对目前蔬菜田常发生的2种优势叶螨二斑叶螨Tetranychus urticae和截形叶螨T. truncatus的杀螨活性,于室内采用离体叶碟法测定其对这2种叶螨产卵及发育的影响,于室外采用活体植株评价该药剂对2种叶螨的田间防效。结果表明,经复配杀螨剂联肼·乙螨唑及其单剂处理2种叶螨雌成螨24 h后,死亡率为20.50%～54.98%,均显著高于清水对照;联肼·乙螨唑处理较清水对照显著降低了2种叶螨卵发育至若螨期的比率,联肼·乙螨唑处理后二斑叶螨和截形叶螨的若螨率分别为4.91%和1.63%。田间试验中联肼·乙螨唑对2种叶螨具有一定的速效性,药后3 d对二斑叶螨和截形叶螨的防效分别达95.74%和89.83%,药后7 d防效分别为98.03%和99.44%,显示了优良的防控效果及持效性。表明复配杀螨剂联肼·乙螨唑可用于田间蔬菜优势叶螨种群的高效防控。     

The potential of the hatay population ofPhytoseiulus persimilis to control the carmine spider miteTetranychus cinnabarinus in strawberry in Silifke - Icel, Turkey

The Hatay population of the predatory mitePhytoseiulus persimilis Athias-Henriot was released into a commercial field of cv. ‘Chandler’ strawberries for the control ofTetranychus cinnabarinus Boisduval (Acari: Phytoseiidae: Tetranychidae) in 2000 and 2001 in Silifke county of Icel on the East Mediterranean coast of Turkey. In 2000, populations ofT. cinnabarinus were recorded in the field from the beginning of March in most plots, and increased gradually until mid-May.T. cinnabarinus populations declined to very low levels in all predator release plots approximately 2 weeks after reaching a peak. In general, predator populations rose linearly as the population densities of spider mites increased until mid-May.P. persimilis numbers peaked during the period 16–23 May. A similar scenario developed in 2001, but because of the relatively high number ofT. cinnabarinus in all plots at the beginning of the experiment, bothT. cinnabarinus andP. persimilis peaked almost one month earlier than in 2000. In both years, the Hatay population ofP. persimilis demonstrated good potential for the control ofT. cinnabarinus in field-grown strawberry in the Silifke region of Icel. http://www.phytoparasitica.org posting Sept. 19, 2002.     

Effect of apple cultivar and of temperature on the biology and life table parameters of the twospotted spider mite<Emphasis Type="Italic">Tetranychus urticae</Emphasis>

Development duration and reproduction rate of the twospotted spider miteTetranychus urticae Koch (Acarina: Tetranychidae) were studied on five different apple cultivars (‘Amasya’ (local cultivar), ‘Golden Delicious’, ‘Granny Smith’, ‘Starking Delicious’ and ‘Starkrimson Delicious’) at 25°C, 65±10% r.h. and 16:8 L:D. In addition, the same parameters were determined on Golden Delicious leaves at three constant temperatures (20°, 30° and 35°C, 65±10% r.h. and 16:8 L:D) in the laboratory.T. urticae performed better on Granny Smith than on the other cultivars, due mainly to high daily egg production (4.6 eggs/♀/day) and the intrinsic rate of natural increase (r _m , which was 0.243 ♀/♀/day). The lowestr _m was observed on Amasya variety (0.231 ♀/♀/day). Development periods of immature stages ofT. urticae varied from 6.5 to 15.5 days at 35° and 20°C, respectively, for females, and from 5.9 to 14.5 days at 35° and 20°C, respectively, for males. The development thresholds of the eggs and pre-adult stages, respectively, were 10.78° and 8.43°C, and total effective temperatures were 57.80 and 172.41 degree-days. Mean generation time (T _o ) of the population ranged from 9.94 days at 35°C to 25.99 days at 20°C. The net reproduction rate increased from 66.99 ♀/♀ at 20°C to 92.19 ♀/♀ at 25°C, and decreased to 84.34 ♀/♀ at 30°C and to 12.04 ♀/♀ at 35°C. The highest r _m occurred at 30°C (0.302 ♀/♀/day) and the lowest at 20°C (0.161 ♀/♀/day). http://www.phytoparasitica.org posting Dec. 19, 2003.     

Spiromesifen toxicity to the spider mite <Emphasis Type="Italic">Tetranychus urticae</Emphasis> and selectivity to the predator <Emphasis Type="Italic">Neoseiulus californicus</Emphasis>

Tetranychus urticae Koch (Acari: Tetranychidae) is a major pest of several agricultural crops and Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) is an important natural enemy of this pest mite. The objective of the study was to evaluate the effect of spiromesifen on the development and reproduction of T. urticae, and to assess the influence of spiromesifen and other acaricides on the population growth rates of the spider mite and its predator, N. californicus. Toxicity tests with spiromesifen at different life stages of T. urticae indicated that eggs less than 72 h old were more sensitive than other development stages. The oviposition rate of T. urticae was significantly affected by spiromesifen. Experiments on the effects of spiromesifen on the growth rates of T. urticae and N. californicus indicated that spiromesifen is innocuous to the predaceous mite but highly toxic to the spider mite, leading to population suppression in 10 days. Fenpropathrin, acephate and neem oil were not harmful to N. californicus, but were not so efficient as spiromesifen in controlling T. urticae, and had significantly less influence on the population growth rates of the spider mite. Among these three products, only neem oil caused significant reduction in the growth rate of T. urticae. Chlorfenapyr, abamectin, milbemectin and diafenthiuron significantly affected the population growth rates of T. urticae and N. californicus. Spiromesifen was the most promising acaricide for managing the two-spotted spider mite, when used in combination with N. californicus.     

二斑叶螨对阿维菌素抗性的CAPS标记

为了实现二斑叶螨Tetranychus urticae Koch对阿维菌素抗药性的快速检测,本研究建立了一种叶螨对阿维菌素抗药性的快速分子检测技术,即酶切扩增多态性序列(cleaved amplified polymorphic sequences,CAPS)标记技术,检测二斑叶螨谷氨酸门控氯离子通道(Glu Cl3)基因片段上G326E的突变频率,并采用琼脂浸叶法测定田间5个种群对阿维菌素的抗药性。结果表明,北京密云、顺义、昌平、浙江宁波和海南吉阳5个种群对阿维菌素的抗性倍数分别达1 155.63、1 317.10、844.19、314.95和1 799.69倍,均为极高抗性水平;CAPS检测发现我国二斑叶螨抗性基因存在G326E位点突变,但在供试的5个不同种群中突变频率变异很大,其中北京昌平种群G326E突变频率高达90.00%,密云和顺义种群均为26.67%,浙江宁波种群为5.00%,而海南吉阳种群不存在该位点的突变。表明该CAPS标记还需与其它抗性机制或检测技术结合来实现叶螨对阿维菌素抗性的早期检测和预警。     

甘肃省二斑叶螨地理种群的遗传分析

为探讨甘肃省二斑叶螨Tetranychus urticae种群遗传多样性及遗传分化,通过mtDNA-COI基因DNA条形码技术对采自甘肃省8个不同生境35个二斑叶螨地理种群的582个样品进行序列分析及地理种群的遗传分化分析。结果表明,获得二斑叶螨mtDNA-COI基因片段大小为424 bp,其中保守序列336个,变异位点66个,简约信息位点45个,单突变位点21个;碱基(A+T)含量明显高于(C+G)含量,有明显的A/T碱性偏倚性;在35个地理种群中共检出16个单倍型,单倍型指数为0.906;Mantel检测结果表明种群间的遗传距离与地理距离无显著相关性;35个地理种群间的遗传分化指数Fst为0.012,种群间变异为1.200。表明二斑叶螨的遗传变异主要来自于种群内部,种群间还未发生明显的遗传分化。     

First record of the invasive mite<Emphasis Type="Italic">Tetranychus evansi</Emphasis> in Greece

The red spider miteTetranychus evansi (Acari: Tetranychidae) Baker and Pritchard was recorded for the first time in Greece, in the area of Tympaki (south-central Crete) onSolanum nigrum. T. evansi is a pest of crops of the family Solanaceae, which are grown extensively in Crete. The species identification was based on both morphological and molecular data. The second internal transcribed spacer was PCR amplified and sequenced in samples from Crete. Sequences were compared with the sequence ofT. evansi from Brazil and with the ITS2 sequences (retrieved from GenBank) of the two closely related tetranychid species most commonly found in Greece,Tetranychus turkestan andTetranychus urticae.     

Physiologic races ofFusarium oxysporum f.sp.melonis in the southeastern anatolia region of turkey and varietal reactions to races of the pathogen

Thirty-four isolates ofFusarium oxysporum f.sp.melonis (F.o.m.) obtained from 205 fields in melon-producing areas in the southeastern Anatolia Region of Turkey were identified on the basis of colony morphology and pathogenicity by the root dip method. In this region the mean prevalence of wilt disease was 88.1% and the mean incidence of disease was 47.5%. Physiologic races 0, 1, 2, and 1,2 of the pathogen were determined by their reactions on differential melon cultivars ‘Charentais T,’ ‘Isoblon’, ‘Isovac’ and ‘Margot’ in the greenhouse. Race 1,2, representating 58.8% (20/34) of all isolates, was widely distributed. Of the other pathogenic isolates, eight were identified as race 0, five as race 1, and one as race 2. This is the first report of physiologic races ofF.o.m. in Turkey. Of 44 melon cultivars tested in the greenhouse for resistance toF.o.m. races, 36 were found to be moderately resistant to race 0, 17 were susceptible to race 1,2, 34.1% were highly resistant to race 1, and 52.2% had moderate resistance to race 2. http://www.phytoparasitica.org posting July 16, 2002.     

甜玉米与木薯间套作对二斑叶螨的生态调控效果

为生态调控我国木薯主产区主要外来入侵害虫二斑叶螨Tetranychus urticae,以甜玉米YT29和食用木薯品种SC9 （抗虫）及工业原料木薯品种SC205 （感虫）为供试材料,系统开展甜玉米与这2种木薯间套种对二斑叶螨调控效果的研究。结果表明,二斑叶螨对SC9表现出非适宜性,而对YT29和SC205表现出适宜性。取食SC9的二斑叶螨各虫态发育历期均显著长于取食YT29和SC205的,幼螨-后若螨死亡率显著高于取食YT29和SC205的,雌、雄成螨寿命显著短于取食YT29和SC205的,单雌产卵量、卵孵化率和雌性百分率均显著低于取食YT29和SC205的,但取食YT29和取食SC205的二斑叶螨的发育和繁殖之间无显著差异。4/YT29-2/SC9间套作模式对二斑叶螨的生态调控效果最好,不仅3年螨害指数显著低于SC9单作、 SC205单作及2/YT29-2/SC205间套作模式,而且其3年平均产量达39.1 t/hm²,显著高于SC9单作 （32.1 t/hm²）、 4/YT29-2/SC205间套作模式（20.5 t/hm²）和SC205单作（12.0 t/hm²）的平均产量。表明甜玉米与抗虫木薯品种间套作模式具有调控虫害、增产的作用,可以在我国木薯种植区大面积推广应用。     

用杂交方法鉴定我国三种常见叶螨

本文报道通过杂交试验,连代隔离饲养观察和阳具端锤的形状区别将北京花卉上发现的绿色种叶螨、红色种叶螨和菜豆上发现的红色种叶螨作了鉴定。绿色种与两红色种之间均存在着生殖隔离,杂交产生不育后代或不能交配,因此它们是各自独立的种。绿色叶螨应是二斑叶螨(Tetranychus urticae),连代隔离饲养证明雌成螨始终体呈绿色(滞育型除外),其遗传性是稳定的,这可以作为二斑叶螨和其近似种相区别的直观特征。从阳具端锤的形状差别可以区分两种红色螨分别是硃砂叶螨(T.cinnabarinus)(采自花卉)和截形叶螨(T.truncatus)(采自菜豆)。据此,作者对国内目前通行的有关棉叶螨(T.urticae)和红叶螨(T.cinnabarinus)的学名和中文名称的混乱问题,进行了讨论。认为棉叶螨不是T.urticae,红叶螨不一定全是T.cinnabarinus。     

玫烟色虫草和球孢白僵菌对朱砂叶螨和二斑叶螨的致病力评价

为探寻具有杀螨潜力的生防真菌,采用喷雾法测定分析玫烟色虫草Cordyceps fumosorosea IF-1106菌株和球孢白僵菌Beauveria bassiana BB-1339菌株对朱砂叶螨Tetranychus cinnabarinus和二斑叶螨Tetranychus urticae卵、幼螨及雌成螨的致病力。结果表明,感染玫烟色虫草IF-1106菌株和球孢白僵菌BB-1339菌株后螨类的形态特征不一致,感染IF-1106菌株后形成棉絮状菌丝,而感染BB-1339菌株后则形成羊毛状菌丝。IF-1106菌株和BB-1339菌株对朱砂叶螨和二斑叶螨卵的LC₅₀分别为2.38×10⁷、8.26×10⁷CFU/mL和4.48×10⁷、1.21×10⁸CFU/mL,对朱砂叶螨和二斑叶螨幼螨的LC₅₀分别1.97×10⁷、8.26×10⁷CFU/mL和7.65×10⁶、8.99×10^5...     

Antifeedant activity of fruit and seed extracts ofMelia azedarach andazadirachta indica on larvae ofSesamia nonagrioides

Methanolic extracts of seeds and fruits of the chinaberry tree,Melia azedarach L. (Meliaceae), showed strong antifeedant activity against 2nd instar larvae ofSesamia nonagrioides Lefèbvre (Lepidoptera: Noctuidae), a very serious pest of maize(Zea mays L.) in Mediterranean countries. Extracts were applied in an artificial diet at concentrations of 1000 and 2000 ppm. The parameters used to evaluate the activity were larval growth rates; quantity of food ingested; phagodepression/phagostimulation index; quantity of frass produced; quantity of material ingested; duration of larval development; and cumulative mortality. Seed extract showed high bioactivity at both doses, while fruit extract proved to be less active, and only at the higher dose used (2000 ppm) did it display a slight antifeedant activity. The activity of theM. azedarach seed extract at the higher dose (2000 ppm) was comparable to that of pure azadirachtin applied at a dose of 1.25 ppm, or to ‘Mubel’, a commercial extract ofAzadirachta indica A. Juss. (Meliaceae), applied at a dose of 75 ppm.     

Species presence and density of tetranychid and phytoseiid mites in unsprayed and sprayed apple orchards in Northern Israel

Species presence and density of mixed populations of phytophagous tetranychid and predacious phytoseiid mites were studied in sprayed and unsprayed apple orchards in northern Israel during three growing seasons. Two species of phytophagous tetranychids, namely,Tetranychus cinnabarinus Boisduval andT. Urticae Koch, and two species of predatory phytoseiid mites —Typhlodromus athiasae Porath and Swirski andAmblyseius swirskii Athias-Henriot — were found. Predator density was lower than herbivore density in sprayed commercial orchards, but the reverse was true in unsprayed orchards. Contribution from the Agricultural Research Organization. No. 2855-E, 1989 series.     

Natural enemies of the pear psylla<Emphasis Type="Italic">Cacopsylla pyri</Emphasis> in treated<Emphasis Type="Italic">vs</Emphasis> untreated pear orchards in Antalya,Turkey

Populations of pear psylla,Cacopsylla pyri (L.) (Rhynchota: Psyllidae), and its natural enemies were sampled on pears in Antalya province during the years 2000–2002. Thirty-two species of predators and three species of parasitoids were detected to be associated withC. pyri in Antalya province. The heteropterans (especially anthocorid species) were the most abundant predator group. Among the anthocorids,Anthocoris nemoralis (Fabricius) (Heteroptera: Anthocoridae), whose population was closely related to the dynamics of the pear psylla population, was generally the principal antagonist ofC. pyri. Other species recorded during the study were the miridDeraeocoris spp., the chrysopidChrysoperla carnea L., and many coccinellid species. Although these predators are polyphagous, as are theOrius species, their populations were related to the psylla fluctuations. Among the parasitoid complex belonging to the order Hymenoptera, the encyrtidTrechnites psyllae (Ruschka) was the only primary parasitoid. Two hyperparasites,viz., Syrphophagus mamitus (Walker) andPachyneuron aphidis (Bouché) (Encyrtidae and Pteromalidae, respectively), were detected in the surveys. Also, this study revealed new information concerning the pear psylla parasitoid complex in Turkey. WhileT. psyllae andS. mamitus are new records to Turkish parasitoid fauna,C. pyri is a new host record forP. aphidis. The population development and abundance of pear psylla and its natural enemies, as well as the parasitization rates in treated and untreated pear orchards, are presented here. http://www.phytoparasitica.org posting May 6, 2004.     

Response of<Emphasis Type="Italic">Tetranychus cinnabarinus</Emphasis> feeding on NaCl-stressed strawberry plants

The development and reproductive rates ofTetranychus cinnabarinus Boisduval (Acari: Tetranychidae), the carmine spider mite, were studied on two strawberry cultivars (Fragaria ×ananassa Duch.; ‘Camarosa’ and ‘Sweet Charlie’) at three NaCl concentrations, 1760, 2400 and 3040 mgl ⁻¹, and control. The effects of NaCl application on the contents of plant nutrients, chlorophyll, proline, peroxidase activity (POX) and proteins were assessed. On Camarosa,T. cinnabarinus had a faster development rate with applications of NaCl than without, except for female development at the highest salinity level. The total development time of females increased with the NaCl concentration, whereas total development time of males decreased. The oviposition period and female longevity on Camarosa was significantly longer in the control than with NaCl, whereas daily and total fecundity were significantly higher at all NaCl concentrations than in the control, except for total fecundity at the lowest salinity level. The total development time, oviposition period, female longevity, daily and total fecundity on Sweet Charlie did not differ significantly between NaCl salinity levels and the control. The intrinsic rate of natural increase (r _m ) on Camarosa and Sweet Charlie were significantly higher with NaCl than in the control. However, the contents of Na, Cl, P, chlorophyll, proline, POX and protein in the two strawberry cultivars changed depending on NaCl concentration. On the other hand, the K and N contents were not affected significantly by NaCl salinity. http://www.phytoparasitica.org posting Nov. 19, 2006.     

Composition,abundance and phytoplasma infection in the hawthorn psyllid fauna of northwestern Italy

Hawthorn (Crataegus monogyna) is one of the natural hosts of Cacopsylla melanoneura, the acknowledged vector of ‘Candidatus Phytoplasma mali’, the causal agent of Apple Proliferation disease, a serious and growing problem for apple production in Europe, particularly in northern Italy. Wild plants could be important sources of both insects and phytoplasmas, but their role in the epidemiology of phytoplasma diseases and their insect vectors has never been thoroughly examined. Cacopsylla melanoneura’s primary host is hawthorn, a plant closely related to apple which often grows wild near orchards. Other psyllid species feed on hawthorn, but no data are available on their possible role as phytoplasma vectors. We investigated the hawthorn’s psyllid fauna in northwestern Italy using yellow sticky traps, beat trays, and molecular analyses from 2003–2005, to study the relationship between hawthorn, the phytoplasma and the insect vector. Population dynamics were monitored, and insects and hawthorn samples were analysed by polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and DNA sequencing for the presence of phytoplasmas. Cacopsylla melanoneura was the dominant psyllid species, followed by C. peregrina, C. affinis and C. crataegi. PCR and RFLP analyses revealed the presence of different fruit tree phytoplasmas in hawthorn plants, and in all four psyllid species.