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.     

Association of the inhibitor of virus replication with resistance mechanisms in pepper cultivars

The kinetics of accumulation of tobacco mosaic virus (TMV) and the S strain of pepper mild mottle virus (PMMV) in resistant and susceptible pepper cultivars was analyzed by enzyme-linked immunosorbent assay (ELISA). Crude protein extracts from noninoculated leaves of the resistant cultivar significantly inhibited TMV replication in tobacco protoplasts. Inoculation with either TMV or PMMV-S caused a slight increase in its inhibitory potency. In contrast, protein extracts from either inoculated or noninoculated leaves of the susceptible cultivar did not inhibit TMV replication in tobacco protoplasts. The protein extracts from the resistant cultivar gave a positive reaction with antibodies against the tobacco inhibitor of virus replication (IVR) in western blotting. The putative role of this IVR-like protein from the resistant cultivar in resistance against TMV is discussed.     

Suppression of powdery mildew in squash by applications of whitewash,clay and antitranspirant materials

The incidence of powdery mildew, caused bySphaerotheca fuliginea (Schlecht. Fr.) Polacci, in squash plants, was suppressed in the field to 50–60% of that in untreated control plants by weekly sprays with whitewash (Loven or Yalbin) or clay. Loven or Yalbin sprays resulted in significant reductions in disease level, more on the adaxial (59–65%) than on the abaxial (38–52%) surface of leaves, and more on young (53–59%) than on old (12–18%) leaves. The addition of 0.1% Dabak (a commercial sticker) to the whitewashes significantly increased their efficiency (22% above that of the controls), the degree of protection being associated with whitewash concentration. Squash leaves were protected from powdery mildew also by weekly sprays of the antitranspirant Vapor Gard, to a level comparable with that achieved by a whitewash plus sticker. However, the protection levels achieved with whitewashes, clays and antitranspirant were lower than with a fungicide (propiconazole). Experiments conducted under controlled conditions resulted in higher rates of escape from infection and a lower rate of hyphal and conidial development on plants and tissues following whitewash, clay and antitranspirant treatments.     

Effect of endotoxic compounds isolated fromVerticillium lecanii on the sweetpotato whitefly,Bemisia tabaci

Toxic products extracted by methanol from intact mycelia ofVerticillium lecanii were tested for their toxicity to eggs, larvae, pupae and adults ofBemisia tabaci and additional insects. All stages ofB. tabaci were sensitive to the toxin, with larvae showing the highest, and adults the lowest, sensitivity. Using a 0.5% crude toxin preparation, the mortality rate ofB. tabaci was 88%, 53.5%, 53.2% and 37% for larvae, eggs, pupae and adults, respectively. High sensitivity of adults, which was characterized by rapid paralysis followed by death, was observed inB. tabaci, Myzus persicae, Aphis gossypii, Acyrthosiphon pisum andFrankliniella occidentalis. Other insects,viz., Heliothis peltigera, Maladera matrida, Carpophilus hemipterus andCeratitis capitata, exhibited significantly lower sensitivity. The toxin was partially purified by differential extraction with organic solvents and on silica gel H and Sephadex LH 20 columns. Based on the toxin inactivation by saponification and its mobility in a polar solvent on thin layer chromatography, it is suggested that the toxic products might be phospholipids.     

Laboratory transmission of the citrus stubborn disease agent by a leafhopper from theCirculifer tenellus complex from the Jordan Valley

Citrus stubborn disease (=little leaf disease) is known to affect the size of citrus trees, and to reduce the quality and quantity of the fruit. The disease agent,Spiroplasma citri, was isolated and culturedin vitro from Oroblanco, orange and grapefruit orchards throughout the year from different regions in Israel. The agent was transmitted by a leaf-hopper from theCirculifer tenellus complex collected onAtriplex halimus plants in the southern Jordan Valley. The latent period of the agent in this vector was at least 10 days following a 3-day acquisition feeding onMatthiola incana plants. It was similar to that found for a primary isolation in culture medium (LP₅₀=21 days). The limitations of visual inspection for recording disease incidence in citrus groves were determined and this method was compared with other methods for detection of the disease agent (immunoassay and cultivation in a culture medium). Plants from various botanical families were tested for their ability to serve as hosts for the Israeli biotype of the beet leaf-hopper and for the stubborn disease agentS. citri. The possible role of IsraeliC. tenellus in the disease epidemiology is discussed.     

Seedborne infection ofAscochyta rabiei in chickpea and its transmission to aerial plant parts

Ascochyta blight of chickpea (Cicer arietinum L.), caused byAscochyta rabiei (Pass.) Labrousse, was found to be both externally as well as internally seedborne in nature, with the external infection being predominant. The pathogen was located primarily on or in the seed coat and in very few cases penetrated into the cotyledons and rarely, to the embryo. Seedling infection resulted from both externally as well as internally seedborne inoculum. The mode of fungal transmission from seed to the foliar plant parts was strictly non-systemic in nature.     

Effects of Neem Seed Derivatives on Brown Planthopper Symbiotes

Populations of intracellular symbiotes declined significantly in brachypterous females of the brown planthopper,Nilaparvata lugens (Stål), which were stressed during nymphal development by caging them on IR20 rice plants treated with 3% neem oil, 5% neem seed kernel aqueous extract, or 10% neem cake aqueous extract. In addition, nymphs grew poorly and symbiote populations in prospective females declined, when reared on rice plants grown in soil treated with neem cake; this indicates systemic action of bioac-tive neem constituents. Addition of custard-apple oil to neem oil did not enhance the inhibitory effects. The effects of neem derivatives on the symbiotes may be either host-mediated — possibly through disturbed neuroendocrine homeostasis, or direct — leading to perturbations of host-symbiote equilibrium.     

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.     

Sex pheromone traps for detecting and monitoring the raisin moth,cadra figulilella,in date palm plantations

Field tests were carried out to determine whether pheromone traps, baited with (Z,E)-9,12-tetradecadienyl acetate (Z9,E12-14:Ac) impregnated in rubber septa (Maavit, Israel), could provide a reliable tool for monitoring the raisin moth,Cadra figulilella (Gregson), in date palm plantations. No significant differences were detected between captures of males in traps baited with 1 or 10 mg pheromone/dispenser. However, traps baited with 1 mg pheromone captured significantly more males than those baited with 0.1 mg pheromone/dispenser. No differences were found between captures of males in traps hung at a height of 8 m (near the bunches) or 2–3 m (on palm trunks). Two peaks of male capture were detected, one in May-June and the other during September-October (ripening period). Results indicate a positive relationship between captures in traps and infestation levels by larvae. Pheromone traps baited with 1 mg Z9,E12–14:Ac impregnated in rubber septa and hung on palm trunks (at a height of 2–3 m), were very useful for monitoringC. figulilella populations and for determining the accurate timing of insecticide applications.     

性引诱剂对蔬菜害虫诱杀效果试验

性引诱剂能有效诱杀斜纹夜蛾（Spodoptora litura Fabr.）、甜菜夜蛾（Spodoptera exigua Hübner）、小菜蛾（Plutella xylostella Linnaeus）成虫,减轻其发生为害,减少使用农药次数。用不同类型诱捕器挂放同种类型诱芯,其诱蛾量不同,UMT-B诱捕器对斜纹夜蛾、甜菜夜蛾的诱捕效果最好,三角形诱捕器对小菜蛾的诱捕效果最好,每667㎡挂放1枚诱芯为宜。     

Effects of pheromone loading, dispenser age, and trap height on pheromone trap catches of the oriental fruit moth in apple orchards

The effects of field aging (0–28 days) and pheromone loading rate on the longevity of red rubber septa loaded with the sex pheromone blend of the oriental fruit mothGrapholita molesta (Busck), were evaluated in North Carolina apple orchards in 2002. Separate field tests examined the influence of trap height and pheromone loading rate of rubber septa on trap catches of adultG. molesta males in an abandoned orchard. The loss of the major pheromone component, (Z)-8-dodecenyl acetate (Z8–12:OAc), from red rubber septa over a 4-week period exhibited a relatively constant release rate with 30, 100 and 300 μg pheromone. Trap catch was significantly higher in pheromone traps placed in the upper canopy than in those in the lower canopy. Pheromone traps baited with 100μg lures caught more moths compared with those loaded with 300 μg. There was no apparent relationship between pheromone trap catch and septa age, with trap catch appearing to be primarily a function ofG. molesta population density. http://www.phytoparasitica.org posting May 14, 2006.     

Development of a pheromone trap monitoring system for orange wheat blossom midge, Sitodiplosis mosellana, in the UK

Field-trapping experiments with synthetic 2,7-nonadiyl dibutyrate, the female-produced sex pheromone of the orange wheat blossom midge, Sitodiplosis mosellana (Géhin), demonstrated that pheromone traps were highly attractive to males and caught very few non-target organisms. Different formulations of pheromone were tested to identify the optimum release rate and dispenser type for use in pheromone traps in the UK. Key findings were that racemic pheromone was as effective as enantiomerically pure (2S,7R)-2,7-nonadiyl dibutyrate, that release rates higher than 0.5 microg day(-1) were not necessary and that the optimal formulation was a 1 mg pheromone loading in a rubber septum. Pheromone traps gave a reliable indication of peak midge emergence, onset of flight and abundance of midges throughout the season. A strong correlation between maximum trap catch and crop infestation levels was obtained.     

(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.     

Trapping Cryptophlebia illepida and C. ombrodelta (Lepidoptera: Tortricidae) in macadamia in Hawaii

Abstract

Two species of Cryptophlebia found in Hawaii's macadamia orchards are active in different parts of a tree canopy. C. illepida (Butler) males were mostly caught in traps hung 1·5 m to 9.1 m from the ground; whereas C. ombrodelta (Lower) males were caught from 9.1 m to 15.2 m. A plastic, cylindrical sticky trap caught equal numbers of C. illepida males as Pherocon 1C traps but more than delta traps. A synthetic pheromone blend of 93% (Z)‐8‐dodecenyl acetate, 4% (E)‐8‐dodecenyl acetate, 1% (Z)‐8‐dodecenol, and 2% (2)‐7‐dedecenyl acetate attracted more males than other blends. No significant differences were detected between the two Cryptophlebia species in their response to the four‐component pheromone blend when traps were hung 4.6 m from the ground.     

Control of the codling moth (cydia pomonella) in apple and pear orchards in Israel by mating disruption

Control of the codling moth,Cydia pomonella (L.) (Lepidoptera: Tortricidae), by pheromone-mediated mating disruption, was studied in Israel using two types of dispensers: Shin-Etsu twist-tie (normal and long-life) and TNO matrix formulation (square wafers). Factors affecting mating disruption: initial pest population density, timing of the pheromone application, early season insecticide treatments and monitoring of the pest, were evaluated. Efficacy of mating disruption was assessed by comparing catch of males in pheromone traps located in pheromone-treated and chemically sprayed control plots. Fruit infestation during the season and at picking time was the major criterion to assess mating disruption. The preferred time for pheromone application was before the first flight of the moth. When pheromones were applied at a later stage, one or two early insecticide sprays had to be used to reduce the initial level of the codling moth population. In all tests, trap catch in pheromone-treated plots was drastically reduced as compared with respective control plots. In pheromone-treated plots where total seasonal trap catch (after pheromone application) was less than 12 males/trap, fruit infestation was less than 1.5%; zero trap catch resulted in 0.1-0.3% infestation. At high population levels, mating disruption was ineffective, with the rate of infestation at picking-time being similar in pheromone-treated and control plots. All the field tests indicated that mating disruption with either Shin-Etsu ropes or TNO squares can control codling moth infestations in apple and pear orchards, at relatively low densities of the pest, as efficiently as commercial insecticide sprays.     

绿盲蝽性诱剂诱捕效率的测定及其影响因子分析

于2015年6月在河南新郑枣园,以红色荧光粉为标记物,采用"标记-释放-回捕"法,对绿盲蝽性诱剂枣园诱捕效率及其影响因子进行了研究。在室内对实验室饲养的绿盲蝽雄成虫进行荧光染色标记,将标记好的雄成虫转移至枣园中心点进行释放,同时按照距释放点一定的距离和方位挂好性诱捕器,释放后连续7d进行回捕,回捕后进行荧光检测。结果表明,7d内绿盲蝽雄成虫的标记回捕率为7.3%;性诱剂有效诱捕半径为10~30m,最佳诱捕半径为20m。性诱剂的诱捕效率还受风向、风速、空气相对湿度等气象因子的影响,位于主导风向上风口的诱捕器,其诱捕量最大。回归分析表明,夜间平均风速与诱捕率存在极显著的线性回归关系,回归方程式为y＝0.540＋0.232x;夜间平均相对湿度与诱捕率有着显著的负相关性,两者的相互关系可用回归方程y＝1.887－0.20x表示。即在一定范围内,夜间风速越大、相对湿度越低越有利于提高绿盲蝽的诱捕效率。     

高剂量性信息素迷向技术防控梨小食心虫的田间应用效果评价

剂量控制是迷向技术防控梨小食心虫的关键，本文通过田间试验研究了新型材料装置固体迷向丝和高剂量自动信息素喷施系统对梨园梨小食心虫的防治效果和持效期，以期探讨新型材料和释放技术在害虫迷向中的应用。结果表明，性信息素在傍晚18：00―20：00对梨小食心虫的诱捕量占全天的93.7%，田间虫量监测以绿色粘胶诱捕器效果较好。常规化学防治处理区对梨小食心虫的平均诱蛾量为42.13头，平均蛀果率为2.64%，相对于常规化学防治处理区，新型材料固体迷向丝、高剂量自动信息素喷施系统处理区平均诱蛾量分别为1.00头、5.31头，对成虫的迷向率分别为91.84%～100%、70.86%～98.25%，平均为97.96%、91.41%，平均蛀果率分别为0.81%、0.95%，在8月采果期的蛀果防治效果分别达85.79%、77.16%，防控持效期可达6个月以上。     

Efficacy of the pear ester as a monitoring tool for codling moth Cydia pomonella (Lepidoptera: Tortricidae) in New Zealand apple orchards

BACKGROUND: The behavioural response of both sexes of codling moth, Cydia pomonella to the pear-derived kairomone (ethyl (2E,4Z)-2,4-decadienoate), codling moth sex pheromone (E,E-8,10-dodecadien-1-ol), and sex pheromone combined with the pear derived kairomone loaded into red rubber septum were investigated in trapping experiments in New Zealand apple orchards. A range of 0.01-10.0 mg of pheromone loading in rubber septum dispensers was tested and the highest catch of males was in traps baited with 1.0 mg. No dose response in trap catch of males was seen in traps baited with different amounts of pear-derived kairomone (0.01-10.0 mg). RESULTS: The number of females caught was significantly affected by the amount of pear derived kairomone used to bait traps, with the highest catch obtained at 10 mg loading. The attractiveness of sex pheromone was not enhanced by the addition of the kairomone either when used in the same bait or in a separate bait. The mean number of males captured in traps was reduced by 44% when the pheromone and kairomone were combined at ratio of 1:1 (0.1 mg pheromone: 0.1 mg kairomone) in separate sources. CONCLUSION: Kairomone baited traps showed some potential for monitoring the flight activity of female C. pomonella in apple orchards in two locations (Canterbury and Hawke's Bay). However, the number of male moths caught was low as compared to the number of male moths caught in pheromone-baited traps, and therefore the sex pheromone should continue to be used for monitoring male activity.     

暗黑鳃金龟性信息素田间应用的初步研究

系统研究比较了暗黑鳃金龟性信息素比例、剂量、溶剂类型、诱芯载体类型、诱捕器种类以及诱捕高度等几种因素对诱捕量的影响。结果表明,当L-异亮氨酸甲酯∶R-(-)-芳樟醇为4∶1,总剂量为100 mg时诱捕效果明显好于其他设置;并且发现二氯甲烷做溶剂、绿色天然橡胶塞为诱芯载体、采用自制诱捕器并设置于1.5 m的高度时诱捕效果最佳。     

Developing Pheromone Traps and Lures for Maruca vitrata in Taiwan

The larvae of the legume pod borer, Maruca vitrata (Lepidoptera: Pyralidae), cause severe damage on economically important legume crops in the tropics. The female moth produces volatile components to attract males for mating. The so-called sex pheromones are species-specific multi-component blends and are used as lures in crop protection for pest monitoring. Their chemical identification and ratios is critical to design efficient lures. The following sex pheromone components for M. vitrata have been described: (E, E)-10,12-hexadecadienal (major compound), (E, E)-10,12-hexadecadienol and (E)-10-hexadecenal (minor components). The ratio of 100:5:5 of these components was the most attractive in trapping experiments in Benin, Africa. According to this ratio, a synthetic pheromone lure was developed for commercial use. But the commercially available blend was not attractive in field trapping experiments in other regions of sub-Saharan Africa and Southeast Asia. These findings lead to the conclusion that there is a possible polymorphism in the blend composition of the M. vitrata sex pheromone among populations from different geographical regions. In Taiwan, M. vitrata moths were never caught efficiently by the commercially available pheromone lures and traps. This paper reports trap and lure optimization experiments for effective trapping of Taiwanese M. vitrata moths in different leguminous crops.