Traps baited with pear ester and acetic acid attract both sexes of Hedya nubiferana (Lepidoptera: Tortricidae)

This study was initiated with the objective of studying field responses of the green budworm moth, Hedya nubiferana (Haworth) (Lepidoptera: Tortricidae), to pear ester [PE; ethyl (E,Z)‐2,4‐decadienoate] and acetic acid (AA) with the aim of developing a lure attractive also for females. In the overwhelming majority of tests, traps baited with the PEAA lure (the combination of both PE and AA) caught more than traps baited with either of the constituents presented alone. PEAA lures were attractive to H. nubiferana no matter whether the two compounds were provided in separate dispensers or mixed together in a single one, and a large percentage (up to 71%) of trap catch consisted of females. Traps with PEAA lures caught (females plus males) on an average 30% of the catches in traps baited with the synthetic green budworm moth sex pheromone (only males). This suggested that the new PEAA lure had a trapping performance comparable with that of pheromone traps, which latter are used by farmers today. Consequently, the PEAA lure showed potential for future practical applications as a female‐targeted lure for H. nubiferana. To our knowledge, this is the first well‐documented report on the attraction of PEAA lure for a tortricid species other than codling moth.     

Developing female removal for Cydia pomonella (Lepidoptera: Tortricidae) in organic pear in the USA and Italy

Seventeen trials were conducted using traps baited with kairomone-based lures to evaluate female removal (FR) as an effective management tactic for codling moth, Cydia pomonella, L., in organic pear, Pyrus communis L., production in Italy and USA during 2019–2020. Studies included paired plots (0.4–1.4 ha) treated with or without 60 traps ha⁻¹ in cultivars Bartlett and Abate Fétel. Paired plots were also treated together with or without mating disruption (MD) and with similar spray programmes. Three-, four-, and five-component lures were used with several trap types: green, clear or green/white bucket traps and orange delta traps. The three-component lure consisted of (E,E)-8,10-dodecadien-1-ol (sex pheromone, PH), (E,Z)-2,4-ethyl decadienoate (pear ester, PE) and acetic acid (AA); the four-component lure was PE, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), 6-ethenyl-2,2,6-trimethyloxan-3-ol (pyranoid linalool oxide, LOX), and AA, and the five-component lure had PH added. Preliminary studies were also conducted to evaluate the trapping efficacy of non-saturating bucket traps. A clear bucket trap baited with PE/DMNT/LOX + AA captured 97-fold more codling moth females than an orange delta trap baited with PH/PE. However, female captures did not differ between traps when both were baited with the four-component lure. Fruit injury from codling moth was significantly reduced with the implementation of FR in both pear production regions. At harvest, mean fruit protection in the USA studies was 65% and 27% in Italy. This difference was likely associated with the four-component lure being less effective in Italy than in the USA. Nevertheless, results demonstrate that FR can be a useful approach to remove females immigrating into orchards and as a new tactic to reduce pest pressure in selected areas of orchards allowing both MD and organic insecticide programmes to be more effective. Further studies should investigate the cost-benefit of matching the intensity of FR to variable pest pressures.     

梨小食心虫化学通信中的信息物质

梨小食心虫Grapholitha molesta Busck是我国北方果区发生的重要害虫。当前对该虫的防治主要依赖化学农药, 但引起的害虫抗药性、 杀伤天敌和环境污染等问题非常严重。食心虫自身的信息素、 寄主/非寄主的他感化学物质对于调节其配偶选择和寄主定位起着至关重要的作用, 基于信息化学物质的害虫管理策略为果园食心虫的治理提供了新的途径。本文综述了国内外有关梨小食心虫化学信息物质研究进展, 包括雌蛾释放的性信息素组分及对雄、 雌两性的引诱, 雄蛾释放的信息素, 利用性信息素的迷向研究, 寄主植物挥发性引诱物质的鉴定和筛选, 以及梨小食心虫寄主转换机制等方面的研究现状和存在的问题。具体来说, 雌蛾的性信息素包括顺-8-十二碳烯醋酸酯、反-8-十二碳烯醋酸酯、顺-8-十二碳烯-1-醇和十二碳-1-醇, 各个组分的比例在地理种群间存在变异。在室内, 通过行为试验证实两种醋酸酯对雄蛾的引诱是必不可少的, 微量的顺-8-十二碳烯-1-醇对二元组分起到增效作用。在田间, 上述3种物质组成的诱芯具有较强的活性; 由此开发的性信息素迷向技术（人工迷向丝、 可喷施的微胶囊和蜡滴）被用于梨小食心虫交配干扰, 取得了很好的效果。梨小食心虫最主要的寄主植物桃梢挥发物包括22种化合物, 其中绿叶挥发物占到50%, 行为生测证实6~8个碳原子的物质是主要的活性化合物。顺-3-己烯丁酸酯、顺-3-己烯醇、反-2-己烯醛、苯甲醛和苯甲腈的五组分混合物, 其引诱力与天然桃梢挥发物相当。通过钙成像试验证实, 尽管苯甲腈在桃梢天然挥发物中仅占0.14%, 但雌蛾对含有该物质的混合物有显著趋性, 该物质对梨小食心虫成功识别寄主具有重要意义。最后对梨小食心虫信息化学物质下一步的研究和应用前景进行了探讨。     

Isolation of microsatellite loci in the codling moth,Cydia pomonella (Lepidoptera: Tortricidae)

Cydia pomonella L. is an important insect pest of pome fruits worldwide. We have isolated and characterized 17 microsatellite loci from the enriched genomic libraries constructed using a biotin/streptavidin capture protocol. Among these loci, 11 were scored polymorphic when 50 individuals from a laboratory population were screened. Their alleles numbered two to four, with the observed heterozygosity (H_O) ranging from 0.114 to 0.404. Successful amplification was obtained for all these loci when the designed primers were tested, showing the promise of use in genetic mapping and population studies.     

苹果蠹蛾性信息素的研究和应用进展

苹果蠹蛾Cydia pomonella (L.)是我国重要的检疫害虫, 在我国仅分布于新疆和甘肃以西局部地区, 但一直保持向我国东部扩张的趋势。在国际上, 利用性信息素监测和迷向防治苹果蠹蛾已经成为一种切实可行并广泛应用的害虫管理技术。本文综述了苹果蠹蛾性信息素的成分鉴定、人工合成和应用情况的研究进展, 指出了目前存在的问题和应用前景, 以期为我国苹果蠹蛾的防控策略的研究和应用提供参考。     

Insect-oriented locomotor responses by unmated females of Ephestia cautella (Walker) (Lepidoptera: Phycitidae)

Unmated E. cautella of both sexes were caged together and the ensuing behaviours of females were recorded, with particular attention to orientations to other insects. Calling females engaged in ‘turning-to-face’ and ‘walking up to’ orientations directed almost exclusively at wing-beating males (flying, or sexually excited and ambulatory). Non-calling, locomoting females engaged in ‘flying at’, ‘landing near’ and ‘walking into’ orientations directed predominantly at wing-beating or resting males, and occasionally at mating pairs or at calling females. The activities of the orienting female led to changes in the behaviour of some target insects, and 4% of all females mated directly after approaching males. Results are discussed in relation to sexual receptivity, locomotory excitation, and the pheromonal control of this species.     

Reduction of the response to sex pheromone in the oriental fruit moth,Grapholita molesta (Lepidoptera: Tortricidae) following successive pheromonal exposures

The effects of prior pheromonal experience upon the pheromone- mediated upwind flight response was examined in the oriental fruit moth, Grapholita molesta(Busck) (Lepidoptera: Tortricidae). Adult male G. molestawere subjected to a parallel series of staggered and repeated pheromonal exposures in a sustained-flight wind tunnel. Levels of response to pheromone in male G. molestasignificantly decreased in a (a) rectilinear function with increased ages of individuals, (b) logarithmic function of successive trials, and (c) steeper logarithmic function of successive trials with increased dosage of sex pheromone. The baseline levels of responding were not affected by either the (a) dosage of sex pheromone, (b) posteclosion ages of individuals for their initial exposures once the main effect of age itself was estimated, (c) elapsed time in hours between trials, or (d) discrete days of testing as integral intervals, disregarding hours within days.     

Recognition and avoidance of previously laid egg masses by the oblique-banded leafroller (Lepidoptera: Tortricidae)

Investigations were conducted on oviposition by laboratory-reared oblique-banded leafrollers, Choristoneura rosaceana Harris. In paperbag oviposition chambers, females deposited their egg masses in a significantly nonrandom, uniform manner in 16 of 20 replicates. Inpetri dish oviposition chambers, gravid females were exposed to egg masses recently deposited by other females. As determined by the magnitude of the mean direction vector of the second egg mass in relation to the first, females detected and avoided egg masses laid by other females. In addition, they avoided waxed paper from which a recently oviposited egg mass had been removed. This phenomenon is most likely due to a pheromone laid down with each egg mass.     

The role of abiotic factors in the pupation of Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae) in the soil

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Fluctuating asymmetry in antlers of fallow deer (Dama dama): the relative roles of environmental stress and sexual selection

Antler lengths were recorded of a total of 250 male fallow deer (Dama dama (L)). Animals sampled were from marked populations where the majority of individuals were of known age. Asymmetry in antler length was normally distributed with a mean not significantly different from zero, confirming that differences in length between the antler pair constitute a true fluctuating asymmetry (FA). We found no clear relationship between the degree of asymmetry in antler length of an individual male and either population density or actual body mass. We did, however, detect a significant relationship between asymmetry and deviation from maximum cohort bodyweight. If deviation from maximum weight within a cohort may be considered some index of competitive success or increasing environmental stress, this may suggest that asymmetry in antler length relates in some way to developmental stress suffered by the individual concerned. The degree of asymmetry recorded in antler length also showed a significant decline with animal age, with antlers of animals of 2 years or older showing significantly greater symmetry. This is consistent with a hypothesis that despite continued competition for resources, there is a changing balance of selection pressure as animals reach maturity, with increased pressure from sexual selection requiring males to produce significantly more symmetrical ornaments.     

Radiosensitivity of two strains of the codling moth Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) originating from different elevations in Armenia

The purpose of this study was to analyse the radiosensitivity of codling moth Cydia pomonella (L.) strains from different elevations, 850 and 2000 m above the sea level. The level of sterility of parental males and inherited sterility of F₁ males in the strain from the higher elevation at all radiation doses (80, 100 and 150 Gy) was significantly lower, than in the strain from the lower elevation. The frequency of chromosomal aberrations in the F₁ generation in the strain from the higher elevation was significantly lower at 80 and 150 Gy than that in strain from the lower elevation. The average number of eupyrene sperm in the F₁ males descended from irradiated males was higher in the strain from the higher elevation than in the strain from the lower elevation. Inheritance of the resistance/susceptible to ionizing radiation were examined by standard genetic cross‐breeding analysis confirming the polygenic nature of the differences in radiosensitivity. The implications of these findings for the implementation of area‐wide integrated pest management programmes that integrate the use of sterile insects are discussed.     

The morphology and development of Nosema carpocapsae,a microsporidian pathogen of the codling moth,Cydia pomonella (Lepidoptera: Tortricidae) in New Zealand

The morphology of Nosema carpocapsae and its development in experimentally infected codling moth larvae are described. Spherical uninucleate meronts were the first stages. Nuclear division produced binucleate meronts which were the most abundant vegetative stage, although additional uninucleate and a few tetranucleate meronts were also observed at this time. All meronts were spherical and ranged from 2.8 to 5.8 μm in diameter. Uninucleate and binucleate fusiform sporonts then appeared followed by some tetranucleate and dividing forms. Oval sporoblasts developed after these and did not divide before maturing into spores. Sporonts were approximately 5.0 to 7.9 × 2.4 to 3.0 μm. Spores developed in all host tissues except the nervous tissue. The binucleate spores showed considerable variation in spore size, 2.4 to 3.9 × 1.3 to 3.1 μm (alcohol fixed, Giemsa stained). The polar filament was usually coiled 11 times (range 9 to 13) at an angle of 53° to the long axis of the spore. Its maximum observed length was 75 μm.     

Comparison of fatty acid composition in total lipid of diapause and non-diapause larvae of Cydia pomonella （Lepidoptera： Tortricidae）

Seasonal changes in the fatty acid composition of the total lipid extracted from the whole body of Cydia pomonella L. larvae were determined by gas chromatography. The six most abundant fatty acids in both non-diapause and diapause larvae of codling moth were oleic （35%-39%）, palmitic （23%-33%）, linoleic （16%-30%）, palmitoleic （5%-10%）, stearic （1.5%-3.0%） and linolenic acids （1.0%-2.5%）. This represents a typical complement of Lepidopteran fatty acids. The fatty acid composition of total lipid of C. pomonella larvae was related to diapause. In similarity to most other reports, the proportion of unsaturated fatty acids increased in diapause initiation state. The total lipid of diapause larvae contained more linoleic acid （25.8% vs. 16.1%） and less palmitic acid （24.7% vs. 33.4%）, than that of non-diapause larvae. The weight percentage of linoleic acid （C 18：2） increased from 16% to 26% from early-August through early-September during transition to diapause, while palmitic acid （C16：0） decreased from 33% to 25% at the same time. These changes resulted in an increase in the ratio of unsaturated to saturated fatty acids （UFA/SFA） from 1.72 in non-diapause larvae to 2.63 in diapause larvae.     

Bionomics of Prays citri (Lepidoptera: Yponomeutidae) and their use in a model of control by male mass trapping*

Abstract. 1. The paper describes the population dynamics of Prays citri (Milliere), relevant to the control of this pest by synthetic pheromone, as well as infestation of lemon trees in various areas and seasons. 2. The responses of males to natural and synthetic sex pheromones are compared, and ratios for the degree of attraction of traps compared with the degree of attraction of competing wild females are calculated. 3. The ratios obtained with various population densities over two seasons of the pest's activity are presented. 4. The data are used in a model simulating control of Prays citri by male mass trapping.     

Control of Ichneumonoptera chrysophanes (Meyrick) (Lepidoptera: Sesiidae) by mating disruption in persimmons

Abstract A ca 0.62 ha block of 480 persimmon trees at Woombye, Queensland, was treated with the pheromone of Ichneumonoptera chrysophanes emitted from polyethylene dispensers placed at a rate equivalent to 1480/ha early in September 2000. A second block of 219 trees was left untreated and served as the control. The technique was assessed using traps to measure the ability of I. chrysophanes males to locate synthetic pheromone baits, and by the incidence of fresh damage detected during December and June surveys of a minimum of 67 trees in each block. Pheromone release rates were determined approximately weekly by measuring the amount of pheromone remaining in a sample of 10 dispensers suspended within the treated block. A second orchard at Amamoor, Queensland, was partly treated with pheromone applied at a similar rate, but was monitored only in terms of trap catch. No assessments were made of damage levels. Mean pheromone-release rates ranged from 15.8 to 1.6 mg/ha/h. Over the entire period of the trial, from 8 September 2000 to 27 June 2001, no males were caught in any of the 12 traps in the pheromone-treated block of the Woombye orchard, while 944 were caught in the five traps in the untreated block. The proportion of trees with fresh damage was significantly higher in the untreated block (0.188 and 0.567; December and June surveys, respectively) than in the treated block (0.027 and 0.205), although there was no significant difference between treatments in the mean number of strikes/infested tree in either survey. In the Amamoor orchard no moths were caught in any of the 32 traps in the treated blocks, compared with a total of 303 in the 13 traps in the untreated block.     

Effects of moth size on velocity and steering during upwind flight toward a sex pheromone source byLymantria dispar (Lepidoptera: Lymantriidae)

Free-flying male gypsy moths (Lymantria dispar)head upwind in response to sex pheromone. Males typically fly in a zigzag path, with mean ground speeds modulated by pheromone concentration and ambient temperature, but not by wind speed. We studied the effect of male size on ground speeds and additional flight track parameters. Mean net ground speed along the wind line was fastest among large males and was slower in medium and small males. Similarly, mean airspeeds and ground speeds along the flight tracks increased from small to large males. Males from all three size classes steered similar mean course angles. Small males, however, had larger mean track angles than larger males, and mean drift angles were also larger for small males. Turning rates (frequency of turns across the wind line) and interturn distances (net crosswind displacement between turn apices) were not significantly different among the three size classes; however, large males had a trend toward a reduced mean turning rate and increased mean interturn distance. The steering of similar course angles by males from all three size classes and the higher airspeeds among larger males (the two variables males can actively control during free flight) suggest that changes in other flight parameters are a result primarily of increased ground speed among large males.     

Control of diapausing codling moth,Cydia pomonella (Lepidoptera: Tortricidae) in wooden fruit bins,using entomopathogenic nematodes (Heterorhabditidae and Steinernematidae)

Stacked wooden fruit bins are frequent overwintering sites for overwintering diapausing codling moth larvae. Control strategies against the codling moth (Cydia pomonella) (Lepidoptera: Tortricidae) in South Africa have been hampered by the reinfestation of orchards from nearby stacked infested fruit bins and by the movement of infested bins between orchards. Worldwide, wooden fruit bins are systematically being replaced with plastic bins, however in South Africa this will not be accomplished in the near future. The objective of this study was to evaluate the potential of two recycled commercially available entomopathogenic nematode (EPN) species, Heterorhabditis bacteriophora and Steinernema feltiae, as well as of a local species, Steinernema yirgalemense, to disinfest miniature wooden fruit bins under controlled conditions in the laboratory. After dipping miniature bins loaded with codling moth larvae in a suspension of 25?IJs/mL of each of the three EPN species, under optimum conditions of temperature and humidity, the highest percentage of control was obtained using S. feltiae (75%). The addition of adjuvants significantly increased S. feltiae infectivity to >95%, whereas it did not result in a significant increase in H. bacteriophora or S. yirgalemense infectivity.