Potential of selective insecticides for managing Uraba lugens (Lepidoptera: Nolidae) on Eucalypts

The leaf skeletonizer Uraba lugens Walker (Lepidoptera: Nolidae), an Australian species, locally known as "gumleaf skeletonizer", is well established in New Zealand. This insect has the potential to become a serious pest of forestry and amenity eucalypts (Eucalyptus spp.) and is the focus of a long-term management program. The use of synthetic chemical or biological insecticides is one possible control method within an integrated control program. A series of dose-response trials were conducted using laboratory bioassays to test the efficacy of several insecticides against U. lugens: pyrethroids, spinosad, Bacillus thuringiensis kurstaki Berliner (Btk) and an insect growth regulator, Mimic. Pyrethroids and spinosad proved highly effective against U. lugens larvae, achieving 100% mortality after 3-6-d exposure. The performance of Btk was lower against gregarious skeletonizing larvae compared with solitary chewing larvae. When good coverage of the target foliage is achieved, >90% mortality is possible with Btk. Mimic performed poorly against U. lugens compared with other insecticides tested (<60% mortality). The Eucalyptus species on which larvae were feeding significantly altered insecticide efficacy. Treatments applied to Eucalyptus nitens (Deane & Maiden) Maiden had reduced efficacy compared with E. cinerea F. Muell. ex Benth. or E. fastigata Deane & Maiden. Cooler temperatures also reduced insecticide efficacy, presumably by decreasing movement and food consumption by U. lugens. Recommendations on spray applications to control U. lugens in New Zealand are given.     

Hyperparasitoids of the gum leaf skeletoniser, Uraba lugens Walker (Lepidoptera: Nolidae), with implications for the selection of a biological control agent for Uraba lugens in New Zealand

Abstract  The hyperparasitoids reared from three species of primary parasitoids of the gum leaf skeletoniser, Uraba lugens Walker (Lepidoptera: Nolidae) collected in South Australia and Tasmania are recorded and discussed. Seven hyperparasitoids were reared. Diatora sp. and ? Paraphylax sp. (Ichneumonidae: Cryptinae); Tetrastichus sp. (Chalcidoidea: Eulophidae); Megadicylus dubius (Girault) (Chalcidoidea: Pteromalidae) and Elasmus sp. (Chalcidoidea: Eulophidae) were reared from Cotesia urabae Austin and Allen (Braconidae: Microgastrinae). Megadicylus dubius , Elasmus sp. and Anastatus sp. (Chalcidoidea: Eupelmidae) were reared from Dolichogenidea eucalypti Austin and Allen (Braconidae: Microgastrinae). Pediobius bruchicida (Rondani) (Chalcidoidea: Eulophidae) was reared from Euplectrus sp. (Chalcidoidea: Eulophidae). This appears to be the first record of the cryptine ichneumonid genus Diatora Förster from Australia. Of the seven hyperparasitoid species reared, only one ( P. bruchicida ) is known to be present in New Zealand. Implications for the selection of a biological control agent for U. lugens in New Zealand are discussed. Some prior misidentifications of associated hyperparasitoids are noted.     

Identification of olfactory receptor neurons in Uraba lugens (Lepidoptera: Nolidae) and its implications for host range

Phytophagous insects detect volatile compounds produced by host and non-host plants, using species-specific sets of olfactory receptor neurons (ORNs). To investigate the relationship between the range of host plants and the profile of ORNs, single sensillum recordings were carried out to identify ORNs and corresponding active compounds in female Uraba lugens (Lepidoptera: Nolidae), an oligophagous eucalypt feeder. Based on the response profiles to 39 plant volatile compounds, 13 classes of sensilla containing 40 classes of ORNs were identified in female U. lugens. More than 95% (163 out of 171) of these sensilla contained 16 classes of ORNs with narrow response spectra, and 62.6% (107 out of 171) 18 classes of ORNs with broad response spectra. Among the specialized ORNs, seven classes of ORNs exhibited high specificity to 1,8-cineole, (±)-citronellal, myrcene, (±)-linalool and (E)-β-caryophyllene, major volatiles produced by eucalypts, while nine other classes of ORNs showed highly specialized responses to green leaf volatiles, germacrene D, (E)-β-farnesene and geranyl acetate that are not produced by most eucalypts. We hypothesize that female U. lugens can recognize their host plants by detecting key host volatile compounds, using a set of ORNs tuned to host volatiles, and discriminate them from non-host plants using another set of ORNs specialized for non-host volatiles. The ORNs with broad response spectra may enhance the discrimination between host and non-host plants by adding moderately selective sensitivity. Based on our finding, it is suggested that phytophagous insects use the combinational input from both host-specific and non-host specific ORNs for locating their host plants, and the electrophysiological characterization of ORN profiles would be useful in predicting the range of host plants in phytophagous insects.     

Dispersal behavior of the parasitic wasp Cotesia urabae (Hymenoptera: Braconidae): A recently introduced biocontrol agent for the control of Uraba lugens (Lepidoptera: Nolidae) in New Zealand

Estimates of the dispersal range of a recently introduced biocontrol agent in its new environment are vital to understanding its relative searching capacity, and to foresee the maximum area that could be covered in a release event. In New Zealand, the solitary endoparasitoid Cotesia urabae Austin and Allen (Hymenoptera: Braconidae) was first released in January 2011 as a biological control agent for the gum leaf skeletoniser, Uraba lugens Walker (Lepidoptera: Nolidae). The objective of this study was to utilize an experimental approach to quantify the dispersal behavior of one generation of C. urabae. In our experiment, which used sentinel larvae as target hosts, parasitoids dispersed up to 20 m away from the release point but parasitism was highest within 5 m of the release site. A high level of parasitism was observed at the release tree (87.6%) which suggests that most of the females released may have stayed there. According to the dispersal model developed from the data collected, Cotesia would be able to disperse up to 53 m in one release event. In addition, significant differences were found between the different directions tested for dispersal, showing a clear downwind effect on dispersal suggesting that wind has a direct effect on the dispersal behavior of C. urabae in the field.     

Risk posed by the invasive defoliator Uraba lugens to New Zealand native flora

• 1 The risk posed to New Zealand native flora by the recently‐established pest of Australian origin Uraba lugens Walker (Lepidoptera: Nolidae) (gum leaf skeletonizer) was assessed. Weed biological control host range testing methods were applied to identify those New Zealand plant species potentially at risk. Native plants tested were primarily in the Myrtaceae, the family that contains all the Australian hosts of U. lugens.
• 2 Experimental methods included no‐choice larval feeding assays and field cage and laboratory oviposition trials. Difficulty in ascertaining reliable oviposition preference data from cage oviposition trials limited the confidence with which the invader's field host range could be predicted.
• 3 Field surveys of plants attacked by U. lugens in the infested area supported the initial predictions but only some of the at‐risk native Myrtaceae were present in the area.
• 4 The risk to native New Zealand plants is presented in terms of two mechanisms: development of self‐sustaining populations and temporary spill‐over of solitary larvae. Development of self‐sustaining populations of the pest within native forests is deemed to be highly improbable.
• 5 Temporary spill‐over impacts are most likely in urban areas within mixed species plantings or boundaries between native/exotic forests and coinciding with the mobile larval life stages. Spill‐over impacts from U. lugens have only been recorded to date on Metrosideros excelsa.

     

Relative abundance and flight phenology of two pheromone types of Acrobasis nuxvorella (Lepidoptera: Pyralidae)

Two synthetic sex pheromones have been developed and are currently used to detect the flight of the pecan nut casebearer, Acrobasis nuxvorella Neunzig, the most damaging pest of pecan [Carya illinoinensis (Wangenh.) K. Koch]. One pheromone (referred to as standard) is attractive to moths in the southern United States, but not in Mexico. The other pheromone (referred to as Mexican) is attractive to moths in the southern United States and in Mexico. These two pheromones have been implemented by producers as an important tool in monitoring the activity of this pest and have allowed for more efficient pesticide use. In the future, these pheromones could be used as a means of population reduction through pheromone based control methods. Trapping data taken over a 3-yr period were used to determine if phenological differences exist between pheromone types of pecan nut casebearer. The relative abundance of each pheromone type at several locations in the United States also was evaluated. Results of this study indicate that no phenological differences exist between the two pheromone types studied in the United States and that significantly more males are attracted to field-deployed pheromone traps baited with the standard pheromone than to traps baited with the Mexican pheromone.     

Phenology, synchrony and host range of the Tasmanian population of Cotesia urabae introduced into New Zealand for the biocontrol of Uraba lugens

The population dynamics of Cotesia urabae (Austin and Allen) (Braconidae: Microgastrinae), a biological control agent from Tasmania, and its eucalypt feeding host, Uraba lugens (Walker) (Lepidoptera: Nolidae) was investigated prior to its introduction to New Zealand in 2011. Previous host range testing on potential New Zealand non-targets determined C. urabae had some potential to attack an endemic species, Nyctemera annulata (Boisduval) (Lepidoptera: Arctiidae). A closely related species in Tasmania, Nyctemera amica, was thus investigated as a potential host along with the native host U. lugens, to better understand the host range of C. urabae and the synchrony with its host in Tasmania. Adult C. urabae emerged from pupal cocoons in the field during January which confirmed a five month window in which its host, the larvae of U. lugens, was absent in the field. Experiments using sentinel N. amica and U. lugens larvae, field collections of N. amica and of larvae of other Lepidopteran species during this five month time window detected no parasitism by C. urabae. In the laboratory, host specificity testing showed reduced attack rates and no resultant C. urabae eggs or developing larvae or any successful pupation of C. urabae larvae from attacked N. amica larvae. It was concluded that N. amica is most unlikely to be a host for C. urabae in Tasmania and no evidence of any other alternative host was found.     

An evaluation of western bean cutworm pheromone trapping techniques (Lepidoptera: Noctuidae) in a corn and soybean agroecosystem

Pheromone traps can be used to monitor for adult western bean cutworms, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), and for the timing of field scouting. Understanding the effect that different trapping techniques have on adult captures could help corn (Zea mays L.) producers make better pest management decisions. Several approaches to trapping adults were evaluated in 2005 and 2006 by using two different pheromone traps (sticky wing and jug traps) in two different environments (corn or corn/soybean [Glycine max (L.) Merr.] at three different heights (0.6, 1.2, and 1.8 m). There was no significant difference in the trap catches by trap type in either 2005 or 2006. There were significantly more adults captured in traps placed between two cornfields than traps placed between corn/soybean fields during both years. Trap height also was significant, with the traps at 1.2 and 1.8 m catching more moths than traps at 0.6 m during both years. These results show that trapping techniques do affect trap catches and that either trap type placed between two cornfields at either 1.2 or 1.8 m above the ground will maximize trap catches.     

Preliminary studies of Eutorna phaulocosma (Lepidoptera: Oecophoridae) in New Zealand

Abstract

In 1978 George C. Williams predicted that the last two decades of this century would be a fabulous age, and that evolutionary biology would provide critical insights into the processes of change in the biological world. He suggested that these might come to be described as the “good old days”. I am not so sure that this is likely, but I am very sure that it will be a turbulent time. I think also that those biologists who attended the recent SYSTANZ meeting on evolution must by now be equally convinced. The conference was punctuated by heated debates on major topics such as Darwinian and neo-Darwinian theory, vicariance biogeography, and teleology, to mention but a few.     

New Zealand Lepidoptera: Basic biogeography

Abstract

The composition of the New Zealand Lepidoptera fauna is briefly described, and affinities within Tortricidae analysed. Sixty-five genera are used to indicate four possible sets of relationships, but shortcomings of taxonomic interpretations are outlined. Except for species with a wide dispersal range (some 6% of the fauna) most show affinities consonant with terrane biogeography. The panbiogeographic methodology is a potent tool in systematics, giving direction to the research effort.     

Fustiserphus (Hymenoptera: Proctotrupidae) parasitises Lepidoptera in leaf litter in New Zealand

Abstract

The New Zealand proctotrupid Fustiserphus intrudens (Smith) was reared from two species of Tingena (Lepidoptera: Oecophoridae) feeding on leaf litter in Nothofagus forest. Host relationships in the Proctotrupidae are discussed.     

Pest phenology and evaluation of traps and pheromone lures for monitoring flight activity of obliquebanded leafroller (Lepidoptera: Tortricidae) in Minnesota apple orchards

The efficacy of two trap designs (Pherocon 1C "wing" trap versus Pherocon VI "delta" trap) and two pheromone blends for monitoring obliquebanded leafroller, Choristoneura rosaceana (Harris), was evaluated in Minnesota apple orchards during the 2001 and 2002 field seasons. Two distinct flight periods of C. rosaceana were recorded yearly in Minnesota. Overwintered C. rosaceana larvae resumed activity in the spring at approximately 60 degree-days (DD) base 10 degrees C, whereas adult emergence began approximately 275 DD base 10 degrees C. To determine the optimal pheromone blend for monitoring C. rosaceana in Minnesota, traps were baited with either a three-component pheromone blend (Z11-14:Ac, E11-14:Ac, and Z11-14:OH) produced by females in eastern North America, or a four-component blend (Z11-14:Ac, E11-14:Ac, Z11-14:OH, and Z11-14:Al) commonly produced by females in western North America. Of the four pheromone-baited traps evaluated, delta traps baited with the four-component western pheromone lure captured the highest number of C. rosaceana males, followed by wing traps baited with western lure. Male C. rosaceana were less attracted to traps containing the three-component eastern lure, and both lure types seemed to be considerably selective against sympatric redbanded leafroller, Argyrotaenia velutinana (Walker). These results suggest that the pheromonal response of the predominant endemic population of C. rosaceana in Minnesota is similar to the response of the pest in many parts of western North America. The delta trap baited with western pheromone lure of C. rosaceana is recommended for monitoring the pest in Minnesota, and the results are discussed in relation to the development of effective management strategies against this important pest of apple.     

Morphological character evolution in hepialid moths (Lepidoptera: Hepialidae) from New Zealand

Mapping morphological characters on a molecular-based phytogeny enabled examination of character evolution and an historical perspective into evolutionary processes, both of which are important aspects of systematic research and comparative biology. In this study, 63 morphological characters from hepialid moths in New Zealand were mapped on a phylogenetic tree reconstructed from mitochondrial DNA COI & II sequence data. Morphological characters hypothesized to be synapomorphies for the New Zealand 'Oxycanus' lineages and 'Oxycanus' lineage s.s. were confirmed to be homologous when mapped on the COI & II phytogeny. The direction of character state transformation was determined for five characters, with members of the Aenetus and Aoraia lineages exhibiting hypothesized ancestral states. Male genitalic characters were less homoplasious than other character partitions and covaried significandy with phytogeny.     

Major lineages of Nolidae (Lepidoptera,Noctuoidea) elucidated by molecular phylogenetics

To elucidate the evolutionary relationships of the major lineages within the moth family Nolidae, we analysed a molecular dataset comprising eight independent gene regions (6.4 kbp), cytochrome c oxidase subunit I (COI) from the mitochondrial genome, and elongation factor‐1α (EF‐1α), ribosomal protein S5 (RpS5), carbamoylphosphate synthase domain protein (CAD), cytosolic malate dehydrogenase (MDH), glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), isocitrate dehydrogenase (IDH) and wingless genes from the nuclear genome, using parsimony and model‐based evolutionary methods (maximum likelihood and Bayesian inference). Our analyses revealed a well‐resolved phylogenetic hypothesis, again recovering the six previously recognized families within Noctuoidea (i.e. Oenosandridae, Notodontidae, Euteliidae, Erebidae, Nolidae and Noctuidae), and monophyly of the quadrifid Noctuoidea (i.e. Euteliidae, Erebidae, Nolidae and Noctuidae). The family Nolidae is diagnosed and characterized by two synapomorphies from morphology: construction of a ridged boat‐shaped cocoon that bears a vertical exit slit at one end; and two other morphological character states: elongation of the forewing retinaculum into a bar‐like or digitate condition and possession of a postpiracular counter‐tympanal hood. We present a new phylogenetic hypothesis for Nolidae consisting of eight strongly supported subfamilies, two of which are erected here: Diphtherinae, Risobinae, Collomeninae subfam. nov., Beaninae subfam. nov., Eligminae, Westermanniinae, Nolinae and Chloephorinae. Where we are able, each monophyletic lineage is diagnosed by morphological autapomorphies and within each subfamily, monophyletic tribes and subtribes are circumscribed, most of which are also diagnosable by morphological apomorphies. We also describe two new taxa: Gelastocerini trib. nov. and Etannina subtrib. nov. The Neotropical subfamily Diphtherinae, here newly circumscribed, is considered to be the plesiomorphic sister lineage to the rest of Nolidae. Diphtherinae are characterized by loss of the proximal pair of metatibial spurs in males and by the presence of a frontal tubercle, which is presumably associated with a derived strategy of emergence from the cocoon.     

Sex pheromone precursors in Spodoptera littoralis (Lepidoptera: Noctuidae)

Female pheromone gland extracts of Spodoptera littoralis were analyzed for pheromone precursors. Large amounts of fatty methyl esters were found and a positive relationship between the methyl esters and the pheromonal components was observed. The esters were identified on the basis of capillary gas chromatography, coupled gas chromatography with mass spectroscopy and dimethyl disulfide derivatization, and subsequent gas chromatography with mass spectrometry. The characteristic fatty esters of S. littoralis are methyl (Z)-9-tetradecenoate, (E)- and (Z)-11-tetradecenoate, (Z,E)-9,12-tetradecadienoate, (Z,E)-9,11-tetradecadienoate, and (Z)-11-hexadecenoate. The biosynthesis of the monosaturated acids involves probably the common E11 and Z11 desaturases and chain shortening. For the biosynthesis of the novel diene acids, we propose a second, specific desaturation of (Z)-9-tetradecenoate by an E11 desaturase to produce (Z,E)-9,11-tetradecadienoate or by an E12 desaturase to produce (Z,E)-9,12-tetradecadienoate.     

基于性诱和深度学习的草地贪夜蛾成虫自动识别计数方法

[目的]探究深度学习在草地贪夜蛾Spodoptera frugiperda成虫自动识别计数上的可行性,并评估模型的识别计数准确率,为害虫机器智能监测提供图像识别与计数方法.[方法]设计一种基于性诱的害虫图像监测装置,定时自动采集诱捕到的草地贪夜蛾成虫图像,结合采集船形诱捕器粘虫板上草地贪夜蛾成虫图像,构建数据集;应用Y...     

Acoustically mediated pheromone release in Galleria mellonella (Lepidoptera: Pyralidae)

Male greater wax moths, Galleria mellonella L., release pheromone at a controlled rate which attracts females and increase the rate of release in response to female wingbeat, artificial sounds, and substrate vibrations of similar frequencies. Apparatus was developed to detect and measure change in the rate of pheromone release in response to vibrations at specified frequencies. Males increased their rate of pheromone release to a range of frequencies which included most of the energy generated by a wing-fanning female. They were unlikely to respond to sounds and substrate vibrations produced by their honey bee hosts. This ability to distinguish frequencies provides a means for conserving pheromone for use when females are nearby.