Efficiency of the synthetic sex attractant and the effect of trap size on captures ofSpodoptera littoralis males in water traps and in dry funnel traps

The efficiency of the synthetic sex attractant ofS. littoralis and the effect of trap size on male captures in water traps and in newly designed dry traps were investigated. The synthetic attractant was less efficient in attractiveness than virgin females in both small (17 cm) and large (60 cm) traps. Trap size did not affect male captures in traps baited with either virgin females or synthetic pheromone. The dry trap tested was as efficient as the water trap, easier to handle, and highly suitable for monitoring or for mass trapping ofS. littoralis.     

The Use of Sex Pheromones in the Control of Spodoptera littoralis Boisd.1)

An even network of pheromone traps baited with virgin females of Spodoptera littoralis Boisd. was established in Cyprus. By relating trap catches with meteorology it was shown that no major immigration of S. littoralis to Cyprus from surrounding land-masses had occurred. Direct control of S. littoralis by the synthetic pheromones recently synthesized or the sterile male technique may therefore be possible in such an area of ecological isolation.     

Sex ratio and mating status ofSpodoptera Littoralis females collected from light traps in Israel

Spodoptera littoralis moths were collected from two mercury vapor light traps in Israel, sexed, and the females dissected to establish the number of times each had mated. The sex ratio was in favor of males. The higher the percentage of males in the trap, the higher was the corresponding percentage of mated females and number of matings per female. MostS. littoralis females mated more than once. The mating status varied with location and season.     

The use of traps baited with live females or synthetic pheromone as a tool for improving control programs of the cotton leaf-worm,Spodoptera littoralis (Boisd.), in cotton fields in israel

The aim of this investigation was to clarify whether pheromone traps could provide a reliable tool for early detection of aS. littoralis adult population and for indicating infestation by its larvae in the field. The aggregated pattern of distribution of adults is indicated by the fit of data to Taylor’s Power Law or to the negative binomial distribution. However, the relatively high k values obtained indicate thatS. littoralis adults are only slightly aggregated and sometimes almost randomly distributed. Trap position in the field and number of traps per area unit affected size of catches in both female-baited and synthetic-pheromone-baited traps. No relationship between size of catches and temperature, wind velocity or moon phase was detected. Variations in size of catches among traps was not affected much by the baited females. Pheromone traps proved to be a reliable tool for estimating fluctuations in population density and for indicating adult peaks. However, no correlation between male catches and infestation by larvae in the experimental plots was found. Pheromone traps may serve only as a warning device indicating the possibility of potential attack due to an increase in adult population level. Mercury vapor light traps were inferior to pheromone traps in detecting changes inS. littoralis population densities. Synthetic pheromone (“Litlure”) was somewhat less efficient in attracting males than virgin females; however, it is suitable for detecting fluctuations in theS. littoralis adult population.     

Optimized mixture of sex pheromonal components for trapping of maleSpodoptera littoralis in Israel

The sex pheromone gland extracts ofSpodoptera littoralis (Boisd.) in Israel were reexamined by capillary gas chromatography and capillary gas chromatography combined with mass spectrometry. The following compounds were identified: (Z)-9-tetradecenyl acetate (46%), (Z,E)-9,11-tetradecadienyl acetate (33%), (Z,Z)-9,11-tetradecadienyl acetate (4%), (E)-11-tetradecadienyl acetate (9%), (Z)-11-tetradecenyl acetate (7%), and (Z,E)-9,12-tetradecadienyl acetate (0.5-1%). Field tests with various combinations of the major attractant (Z,E)-9,11-tetradecadienyl acetate and the minor components indicated that the best lure forS. littoralis in Israel is 2 mg (Z,E)-9,11-tetradecadienyl acetate containing 0.2-1% of (Z,E)9,12-tetradecadienyl acetate.     

Sex Pheromone Traps for Monitoring the Peach Twig Borer,Anarsia lineatella Zeller: Effect of Pheromone Components,Pheromone Dose,Field Aging of Dispenser,and Type of Trap on Male Captures

The effects of ratio between sex pheromone components, pheromone dose in the dispenser, aging of dispenser in the field, and trap type on trapping efficiency of males of the peach twig borer,Anarsia lineatella Zeller (Lepidoptera: Gelechiidae), were investigated. To attract males, the optimal ratio between pheromonal components in a binary blend containing (E)-5-decenyl acetate (E5-10:Ac): (E)-5-decenol (E5-10:OH) was 72:28 or 83:17. Dosages of 7 or 0.7 mg of the binary blend containing E5-10:Ac: E5-10:OH (72:28) were equally effective in attracting males. The effect of aging of dispenser (Israeli dispensers, loaded with 7 mg pheromone) in the field on trapping efficiency was moderate. Captures in traps baited with 4-week-old septa did not differ from those in traps baited with 1-week-old septa. The fairly slow loss of attractancy exhibited by rubber septa indicates that septa may be used for at least 4–5 weeks. At high population levels, the nonsticky IPS trap was significantly more effective in capturing males than the sticky Pherocon 1C trap; at low populations, however, the Pherocon 1C trap was better.     

性诱剂与黑光灯对二化螟的诱捕效果及其影响因子

在二化螟预测预报中,性诱剂和黑光灯两种诱捕方法被广泛采用,为比较这两种方法对稻田二化螟诱捕效果的差异,于2010—2014年在浙江温岭地区进行了相关研究,并对诱芯和诱捕器种类、田间越冬幼虫量以及气象因子对二化螟诱捕效果的影响进行了研究。结果显示:对于越冬代二化螟,采用性诱剂和黑光灯诱捕的二化螟成虫数量的消长动态基本一致,但采用性诱剂诱捕的成虫峰期出现早、峰次多,而且诱捕量显著高于黑光灯诱捕;不同性诱剂诱芯与诱捕器之间的诱捕效果无显著差异;性诱剂和黑光灯两种方法诱捕的虫量与田间越冬的幼虫基数存在显著正相关关系;两种诱捕方法的诱捕虫量与气温密切相关,对于越冬代,诱捕的虫量与温度呈负相关,而其余各代的诱捕虫量则与温度成正相关。     

(Z)-3-hexenyl acetate and 1-undecanol increase male attraction to sex pheromone trap in Grapholita molesta (Busck) (Lepidoptera: Tortricidae)

The effects of host-plant volatiles (HPVs) on male oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), and response to sex pheromone trap were studied in a pear orchard. Two HPVs compounds, (Z)-3-hexenyl acetate and 1-undecanol, combined with sex pheromone of G. molesta in traps were tested. The results showed that most of the male moths were captured in the traps baited with the sex pheromone combined with these two HPVs compounds than by the pheromone alone. Also, more males were captured by the trap containing pheromone plus (Z)-3-hexenyl acetate than by the one containing 1-undecanol. It appeared that these HPVs act as sex pheromone synergists to enhance the attraction of male G. molestato pheromone traps, since males were not captured in the traps baited only with (Z)-3-hexenyl acetate and/or 1-undecanol.     

Olfactometer and trap for evaluating attractants for the mediterranean fruit fly,Ceratitis capitata

An olfactometer for laboratory evaluation of Mediterranean fruit fly [Ceratitis capitata (Wied.)] attractants is described. The olfactometer cage with horizontally rotating wheel on which to suspend traps, is basically a smaller version of that described by Gow in 1954. The trap design prevents direct contact of trapped flies with the experimental attractant, provides for their survival, and allows for their reuse in subsequent tests. One or more attractants can be tested simultaneously using flies of known age, sex and physiological condition.     

Azetidine-2-carboxylic acid: A naturally occurring inhibitor ofSpodoptera littoralis (boisd.) (Lepidoptera: Noctuidae)

Ruscus hypoglossum andUrginea maritima (Liliaceae) are highly resistant toSpodoptera littoralis. The foliage of these plants contains a proline analog, L-azetidine-2-carboxylic acid (AZA): inUrginea at a concentration of 1.7% of fresh weight and inRuscus at a concentration of 0.019%. The concentration of AZA inUrginea accounts for its lethal effects onS. littoralis larvae and for the direct effect of an acetone-soluble 80% methanol extract on adultS. littoralis, as evidenced by reduced viability of eggs deposited. The toxicity ofRuscus extracts is only partly attributable to AZA content.     

Non-target beetles (Coleoptera) in Trypodendron pheromone traps in Finland

Non-target beetles were surveyed in Trypodendron pheromone traps in 3 localities in Finland. Two window traps baited with Trypolure, containing lineatin dissolved in ethanol, and one control trap without attractant were used in each locality. A total of 1648 specimens belonging to 223 non-target species were recorded. The species were divided into five ecological groups to be treated separately. Hylurgops palliatus and Hylastes cunicularius were abundant in baited traps, whereas other scolytids as a group did not show clear attraction. Other species living in recently dead trees, including bark- and wood-boring species and associated species (predators, scavengers, fungivores, etc.), were clearly attracted by Trypolure. The most abundant ones were Hylecoetes flabellicornis, Thanasimus formicarius, Rhizophagus dispar, and Rhizophagus nitidulus. Although numerous in the samples, saproxylic species inhabiting more decayed wood and non-saproxylic species did not seem to be attracted. Grouping of species into ecological groups was helpful in the search for attraction patterns among species that usually are scarce in pheromone traps.     

二化螟性诱芯中不饱和十六醛的比例对诱捕效果的影响

作者于2006年夏季在河南信阳地区系统比较了二化螟性诱芯中Z11-/Z9-16∶Ald及Z13-18∶Ald剂量对2个世代的二化螟雄蛾诱捕量的影响。结果表明,二化螟越冬代成虫诱捕试验中,2个最佳配方中Z11-/Z9-16∶Ald分别为9∶1和8∶2,而比例在7∶3~1∶9之间的诱芯则无引诱作用。如果保持诱芯中Z11-16∶Ald和Z9-16∶Ald的剂量一致且质量比控制在2∶1,则二化螟诱捕量随诱芯中所含Z13-18∶Ald剂量的增加而下降。所有诱芯在二化螟第一代引诱效果显著下降,但该时期组分为Z11-16∶Ald(2)、Z9-16∶Ald(1)、16∶Ald(0.7)和Z13-18∶Ald(0.37)的诱芯诱捕量显著优于其他配比。     

Captures ofEarias insulana males in water traps and dry funnel traps baited with synthetic pheromone or virgin females

(E, E)-10,12-hexadecadienal (HDD) effectively attracted males ofEarias insulana (Boisduval) when released from polyethylene vials but not from rubber dispensers. Traps baited with 3 mg HDD/trap were as effective in luring males as traps baited with four virgin females. Funnel traps baited with either HDD or virgin females captured significantly more males than water traps baited with the same lures.     

Sex Pheromone Traps for Monitoring the European Vine Moth,Lobesia botrana: Effect of Dispenser Type,Pheromone Dose,Field Aging of Dispenser,and Type of Trap on Male Captures

The effects of dispenser type, pheromone dose in the dispenser, aging of dispenser in the field, and trap type on trapping efficiency of males of the European vine moth,Lobesia botrana Den. et Schiff. (Lepidoptera: Tortricidae), were investigated. LB Pherocon caps and locally manufactured septa were equally effective in attracting males to traps. Within the range of 0.1 to 100 μg pheromone/dispenser, response of males increased positively with the pheromone dose. Within the first 7 days tested, pheromone loads of 1 or 10 mg/dispenser were significantly less attractive to males than 0.1 mg/dispenser. The effect of aging of the dispenser (loaded with 1 mg pheromone) in the field on trapping efficiency was significant. Captures in traps baited with 4- and 5-week-old septa were significantly lower (by 24%) than those in traps baited with 1-week-old septa. The fairly slow loss of attractancy exhibited by rubber septa indicates that septa may be kept in traps for at least 5 weeks. The release rate of the pheromone from the Israeli dispensers (1 mg loaded) was measured in a flow system. The emission of the pheromone decreased gradually as a function of age, correlating well with the lower trap catches of field-aged septa. Release rates were reduced by 56%, 70% and 84% after 4, 5 and 6 weeks, repectively. The nonsticky IPS trap was as effective in capturing the European vine moth males as the sticky Pherocon 1C trap. The possibility of using the non-sticky, nonsaturating and easy-to-handle IPS traps may lead to better and easier monitoring of the European vine moth populations.     

Floral attractants for the female soybean looper, Thysanoplusia orichalcea (Lepidoptera: Noctuidae)

BACKGROUND: The soybean looper, Thysanoplusia orichalcea (F.), is a polyphagous insect pest of vegetable crops. Indonesian in origin, it has spread to Europe, India, Africa, Australia and New Zealand. The identification of an attractant for female T. orichalcea could enable the development of alternative pest management strategies to those provided by insecticides or sex pheromones, which are often only attractive to males. RESULTS: Traps baited with synthetic lures derived from Canada thistle, Cirsium arvense (L.) Scop., floral volatiles attracted female T. orichalcea. Phenylacetaldehyde, a floral compound attractive to many Lepidoptera and present in C. arvense, was tested alone as an attractant for the soybean looper and caught significantly more female than male T. orichalcea. Trap catch was greatest when phenylacetaldehyde was combined with five prevalent volatiles present in C. arvense headspace collections: 2‐phenylethyl alcohol, methyl salicylate, dimethyl salicylate, benzaldehyde and benzyl alcohol. Twice as many female moths as males were collected. CONCLUSION: Successful trapping of female T. orichalcea in either a lure‐and‐kill or a mass trapping system may offer an effective way to manage its population size. Copyright © 2008 Society of Chemical Industry     

The effect of IKI-7899, a new chitin synthesis inhibitor,on larvae ofTribolium castaneum andSpodoptera littoralis

The effect of IKI-7899 and diflubenzuron on larval development and emergence ofTribolium castaneum and ofSpodoptera littoralis was determined. The LC₅₀ of IKI-7899 at adult emergence ofT. castaneum larvae fed the compound in their diet and the ED₅₀ of S.littoralis larvae treated topically were approximately one-sixth those of diflubenzuron.     

青岛地区暗黑鳃金龟性信息素鉴定及田间应用技术

为深入了解国内暗黑鳃金龟Holotrichia parallela Motschulsky种群的性信息素组分及其田间引诱效果,采用气质联用技术对其雌性信息素进行了分离鉴定,利用标记-回捕技术测试了5 h内暗黑鳃金龟的扩散距离,并在此基础上测试了诱捕器颜色、离地高度、密度、单诱芯性信息素含量等对田间诱虫效果的影响。结果表明：L-异亮氨酸甲酯和（R）-（-）-芳樟醇为国内青岛种群暗黑鳃金龟雌虫性信息素的主要组分,两者含量比为7：1;暗黑鳃金龟5 h扩散距离可达400 m以上,平均扩散距离为55.9 m,扩散距离在20~60 m的个体占总虫数的77.5%;黄色诱捕器对该虫的引诱效果显著优于黑色和绿色;诱捕器离地2 m引诱到的试虫数目显著高于1、1.5、2.5和3 m;单个诱芯性信息素含量360 mg引诱效果最好,显著高于180 mg及以下浓度;诱捕器间隔20~60 m防治效果较好,结合使用成本和试虫扩散距离,间距60 m最优。     

Sex pheromone traps for monitoring the honeydew moth,Cryptoblabes gnidiella: Effect of pheromone components,pheromone dose,field aging of dispenser,and type of trap on male captures

The effects of pheromone components, pheromone dose in the dispenser, aging of dispenser in the field, and trap type on trapping efficiency of males of the honeydew moth,Cryptoblabes gnidiella (Mill.) (Lepidoptera: Pyralidae), were investigated. At dosages of 2 or 0.2 mg, a binary blend containing (Z)-11-hexadecenal (Z11–16: Aid) and (Z)-13-octadecenal (Z13–18:Ald) (1:1) was as effective in attracting males as a quaternary blend containing Zll-16:Ald, (E)-11-hexadecenal (Ell-16:Ald), Z13–18:Ald and (E)-13-octadecenal (E13–18:Ald), (10:1:10:1). Within the range of 20 to 2000 μg pheromone/dispenser, response of males increased positively with the pheromone dose; however, a load of 10 or 20 mg/dispenser was significantly less attractive to males than 2 mg/dispenser. The effect of aging of the dispenser in the field on trapping efficiency was significant. Captures in traps baited with 3- and 4-week-old septa were lower than those in traps baited with 1- or 2-week-old septa. The gradual loss of attractancy exhibited by rubber septa indicates that septa should be renewed within 2-3 weeks. The release rate of the pheromone was measured in a flow system and monitored with Zl1– 16:Ald only. The emission was almost constant for 18 days and then decreased gradually until the 34th day. The nonsticky IPS trap was as effective in capturing honeydew moth males as the sticky Pherocon 1C trap. The possibility of using the nonsticky, non-saturating and easy-to-handle IPS traps may lead to better and easier monitoring of honeydew moth populations.     

Response ofSpodoptera littoralis (Boisd.) andEarias insulana (Boisd.) larvae to azadirachtin and salannin

The effect of azadirachtin and salannin, two triterpenoids isolated from seeds of neem (Azadirachta indica A. Juss), on the feeding response ofSpodoptera littoralis (Boisd.) andEarias insulana (Boisd.) larvae, was investigated. Styropor (foamed polystyrene) lamellae were painted on both sides with a mixture of 5% sucrose with different concentrations of either azadirachtin or salannin dissoled in methanol-water (3∶7). Azadirachtin strongly suppressed feeding inS. littoralis larvae even at 0.001%, whereas salannin showed some antifeedant activity at 0.005% and above. Larvae ofE. insulana were deterred from feeding on azadirachtin-treated lamellae even at 0.005%, whereas salannin was effective only at 0.01% and above. Azadirachtin applied on cotton leaves deterred larvae ofS. littoralis from feeding at all concentrations ranging between 0.001 and 0.02%.     

Monitoring of the pine sawyer beetle Monochamus galloprovincialis by pheromone traps in Italy

The pine sawyer beetle Monochamus galloprovincialis (Olivier) (Coleoptera Cerambycidae) gained importance as a pest in Europe after the introduction in Portugal of the pine wood nematode Bursaphelenchus xylophilus, the agent of pine wilt disease. As the nematode is transmitted by the adult beetles during both maturation feeding and oviposition, effective methods of monitoring of the longhorn beetle populations are needed for the surveillance of the disease spread in Europe. Although in the last years many studies focused on the efficacy of different trapping methods, the general results are still controversial. In this study, we compared the efficiency of two trap types, cross-vane and multi-funnel, and two attractive blends, a kairomonal lure (??-pinene, ipsenol and methyl-butenol) and a commercial kit specific for M. galloprovincialis (pheromone plus kairomonal lure), in order to identify the trap/blend combination more appropriate for the surveillance of the M. galloprovincialis populations. Moreover, the trap efficiency was tested also in a pine stand colonized by M. galloprovincialis after a hailstorm and in a control stand. The results showed that the multi-funnel traps baited with the specific commercial kit was the most effective combination. Interestingly, trap catch was similar in the two pine stands, despite a different density of the target species. As the trapping method was effective also at low population density of M. galloprovincialis, it may be adopted as a general tool for beetle surveillance in the forest and at ports of entry.