Important Quarantine Pest Research Articles

Novel EST-SSRs for an important quarantine pest Liriomyza sativae (Diptera: Agromyzidae) and their cross-species transferability

Novel EST-SSRs for an important quarantine pest Liriomyza sativae (Diptera: Agromyzidae) and their cross-species transferability

Synchytrium endobioticum, the potato wart disease pathogen.

Potato wart disease is considered one of the most important quarantine pests for cultivated potato and is caused by the obligate biotrophic chytrid fungus Synchytrium endobioticum. This review integrates observations from early potato wart research and recent molecular, genetic, and genomic studies of the pathogen and its host potato. Taxonomy, epidemiology, pathology, and formation of new pathotypes are discussed, and a model for molecular S. endobioticum–potato interaction is proposed.TaxonomyCurrently classified as kingdom: Fungi, phylum: Chytridiomycota, class: Chytridiomycetes, order: Chytridiales, family: Synchytriaceae, genus: Synchytrium, species: Synchytrium endobioticum, there is strong molecular support for Synchytriaceae to be transferred to the order Synchytriales.Hosts and disease symptoms Solanum tuberosum is the main host for S. endobioticum but other solanaceous species have been reported as alternative hosts. It is not known if these alternative hosts play a role in the survival of the pathogen in (borders of) infested fields. Disease symptoms on potato tubers are characterized by the warty cauliflower‐like malformations that are the result of cell enlargement and cell multiplication induced by the pathogen. Meristematic tissue on tubers, stolons, eyes, sprouts, and inflorescences can be infected while the potato root system seems to be immune.PathotypesFor S. endobioticum over 40 pathotypes, which are defined as groups of isolates with a similar response to a set of differential potato varieties, are described. Pathotypes 1(D1), 2(G1), 6(O1), and 18(T1) are currently regarded to be most widespread. However, with the current differential set other pathogen diversity largely remains undetected.Pathogen–host interactionA single effector has been described for S. endobioticum (AvrSen1), which is recognized by the potato Sen1 resistance gene product. This is also the first effector that has been described in Chytridiomycota, showing that in this fungal division resistance also fits the gene‐for‐gene concept. Although significant progress was made in the last decade in mapping wart disease resistance loci, not all resistances present in potato breeding germplasm could be identified. The use of resistant varieties plays an essential role in disease management.

Mathematical Modeling of Population Dynamics of Trogoderma granarium (Coleoptera: Dermistidae).

Khapra beetle, Trogoderma granarium Everts, is one of the economically important quarantine pests that mainly feeds on food grain and proteinaceous materials. Its total development time lasts approximately 40-45 d under favorable environmental conditions. Extreme temperatures, high relative humidity (RH), high larval densities, or low food quality can induce a larval diapause, where the insect can survive for up to a few years, occasionally feeding and molting. Ecological modeling is a helpful tool to study the population dynamics of biological systems. Physi-Biological age method is based on temperature-driven development rate, and factors such as RH and food quality were considered as multipliers. The objective of this study was to develop mathematical models to calculate the survival and development of adults, eggs, larvae, pupae, and oviposition and diapause under different environmental conditions such as temperature, RH, and food quality. Algorithms were developed to simulate the population dynamics for each day and coded in C++. The developed models were validated against the literature data and evaluated using linear regression, R2, and MSE. Population dynamics were simulated under Canadian grain storage conditions, and the developed models predicted that the diapausing larvae survived the extremely cold conditions found in Canadian grain. In contrast, other stages did not survive. The surviving larvae developed to pupae and adults, and females began laying eggs once the temperature became warmer in the grain bins.

Potential global distribution of Aleurocanthus woglumi considering climate change and irrigation.

Citrus blackfly, Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae), is an important agricultural quarantine pest, causing substantial economic losses to citrus and many other cultivated crops. Aleurocanthus woglumi is found in tropical and subtropical regions but is presently unknown in Europe and the Mediterranean Basin. We used CLIMEX to model the potential distribution of A. woglumi under an historical climate scenario (centred on 1995), including a spatially explicit irrigation scenario. We found that A. woglumi could potentially invade the Mediterranean Basin, and south-east Asia, including Australia. There is potential for it to invade most of sub-Saharan Africa. Irrigation is revealed as an important habitat factor affecting the potential distribution of A. woglumi, increasing its potential range by 53% in Asia. Under a future climate scenario for 2050, its potential distribution increased across all continents except Africa, where potential range expansion due to relaxation of cold stresses was limited, and was offset by range decrease due to lethal heat or dry stress. As global climates warm, Europe is likely to face a substantial increase in the area at risk of establishment by A. woglumi (almost doubling under the 2050 irrigation scenario). The biosecurity threat from A. woglumi is significant in current citrus production areas and poses a challenge to biosecurity managers and risk analysts.

A Combination Sulfuryl Fluoride and Propylene Oxide Treatment for Trogoderma granarium (Coleoptera: Dermestidae).

The khapra beetle, Trogoderma granarium, is an important quarantine pest of stored-products. While it is not established in the North America, frequent interceptions highlight the need for treatments to eradicate isolated populations if they occur. Methyl bromide has long been the standard fumigant used for this purpose; however, increasing restrictions on its use necessitate the development of new treatment options. Here we evaluate a treatment for khapra beetle using a combination of sulfuryl fluoride (SF) and propylene oxide (PPO). Experiments were conducted to determine the most tolerant stages and the effective rates for each compound. Combination treatments using both products were then evaluated at several temperatures to determine effective doses for quarantine level control. The egg stage was by far the most tolerant to SF, requiring concentration × time (CT) products roughly 10-fold greater than the next most tolerant stage, diapausing larvae. Diapausing larvae were significantly more tolerant to SF than non-diapausing larvae in a recently collected 'field' strain, but not in a more than 30-yr-old 'laboratory' culture. PPO treatments were shown to completely control the egg stage at CTs greater than 155 hr-mgL-1 at both 10 and 20°C. Resulting combination treatments with initial dose rates of 96 and 40 mgL-1 at 10°C and 80 and 40 mgL-1 at 20°C are proposed for SF and PPO, respectively. These combination treatments utilize SF's efficacy against the larval stage along with PPO's superior ovicidal properties to provide enhanced treatment efficacy over each product alone against all life stages of khapra beetle.

A Motor-Driven and Computer Vision-Based Intelligent E-Trap for Monitoring Citrus Flies

Citrus flies are important quarantine pests in citrus plantations. Electronic traps (e-traps) based on computer vision are the most popular types of equipment for monitoring them. However, most current e-traps are inefficient and unreliable due to requiring manual operations and lack of reliable detection and identification algorithms of citrus fly images. To address these problems, this paper presents a monitoring scheme based on automatic e-traps and novel recognition algorithms. In this scheme, the prototype of an automatic motor-driven e-trap is firstly designed based on a yellow sticky trap. A motor autocontrol algorithm based on Local Binary Pattern (LBP) image analysis is proposed to automatically replace attractants in the e-trap for long-acting work. Furthermore, for efficient and reliable statistics of captured citrus flies, based on the differences between two successive sampling images of the e-trap, a simple and effective detection algorithm is presented to continuously detect the newly captured citrus flies from the collected images of the e-trap. Moreover, a Multi-Attention and Multi-Part convolutional neural Network (MAMPNet) is proposed to exploit discriminative local features of citrus fly images to recognize the citrus flies in the images. Finally, extensive simulation experiments validate the feasibility and efficiency of the designed e-trap prototype and its autocontrol algorithm, as well as the reliability and effectiveness of the proposed detection and recognition algorithms for citrus flies.

Combination of Modified Atmosphere and Irradiation for the Phytosanitary Disinfestation of Trogoderma granarium Everts (Coleoptera: Dermestidae).

Simple SummaryThe khapra beetle is defined as one of the most important quarantine pests globally, and fumigating by methyl bromide, one of the ozone-depleting substances under the Montreal Protocol, is a routine measure used for phytosanitary treatment. To protect the Ozone layer, an environmentally friendly measure is needed to be developed. The middle- to late-stage larvae and adults were treated with irradiation, modified atmosphere (MA) alone, and their combinations at room temperature of 24–26 ℃. As a result, late-stage larvae are determined as the most tolerant stage. Ionizing radiation was used to enhance the effects of 1% and 2% O2 MA treatments that the obvious synergistic effects are presented in all combinations, resulted in saving as high as 60% of the estimated exposure times comparing with MA treatment alone. A total of 111,366 late-stage larvae were exposed to a 1% O2 atmosphere for 14 or 15 days after a 200 Gy irradiation, resulted in no survivor in the validating tests. Therefore, the MA-irradiation combination treatment can provide quarantine security at a very high level, it may be combined with international transportation (train or sea container) to disinfest the commodities infested by khapra beetle and other stored products insect pests.The khapra beetle, Trogoderma granarium Everts, is defined as one of the most important quarantine pests globally, and fumigation with methyl bromide, an ozone-depleting substance, is a common phytosanitary measure currently used. The modified atmosphere (MA), irradiation, and their combination treatments of T. granarium larvae and adults were performed at room temperature (24–26 ℃) to develop an ecofriendly phytosanitary disinfestation measure and to shorten the exposure time and overcome treatment disadvantages of irradiation. Late-stage larvae are determined as the most tolerant stage resulted in large LT99.9968 values of 32.6 (29.2–37.5) and 38.0 (35.1–41.7) days treated under 1% and 2% O2 (with N2 balance) atmosphere, respectively. Ionizing radiation was used to enhance the effect of MA and the mortality was highly significantly affected by all the interaction effects, indicating that the synergistic effects present in all the combined treatments. The synergistic ratios, which is defined as the estimated lethal time for MA treatment (LD90, LD99, and LD99.9968), divided by that of combined treatment, were between 1.47 and 2.47. In the confirmatory tests, no individuals recovered from a sum of 111,366 late-stage larvae treated under 1% O2 atmosphere for 14- or 15-d after 200 Gy irradiation, which resulted in validating the probit estimations and achieving an efficacy of 99.9973% mortality at 95% confidence level. Therefore, these treatment schedules are recommended to disinfest T. granarium infecting commodities for phytosanitary purposes under the warehouse, MA packaging, or in combination with international transportation by train or sea container.

Insecticidal Effect of Phosphine on Eggs of the Khapra Beetle (Coleoptera: Dermestidae)

Trogoderma granarium Everts (Coleoptera: Dermestidae) is one of the most important quarantine pests of stored grains. Control of this insect species can be achieved through a gaseous insecticide, phosphine. Many studies focus on the effect of phosphine on different developmental stages of insects, with most of them highlighting eggs as the most tolerant stage. Our data showed that 2-d-old eggs of T. granarium are more susceptible than 1-d-old eggs. Faster hatching was observed in eggs exposed to phosphine for 2 d compared to controls and the result was more pronounced for 1-d-old than 2-d-old eggs. In contrast to the 2-d exposure, hatching rates of eggs exposed to 4 and 6 d were notably reduced, while there was a delay in egg hatching compared to controls. Moreover, larval development from untreated eggs was faster than the larvae from treated eggs, regardless of the exposure time. These dissimilar patters in larval growth may suggest certain delayed effects of phosphine fumigation. The results of the present work can be further utilized for the development of phosphine-based quarantine and pre-shipment treatments for the control of T. granarium.

Variation in susceptibility to insecticides and synergistic effect of enzyme inhibitors in Pakistani strains of Trogoderma granarium

Trogoderma granarium is an important quarantine insect pest of economic importance worldwide. Insecticides are heavily used against this pest that can reduce its susceptibility levels, and if left unchecked, this could lead to misuse of insecticides. Here, the susceptibility of five field strains of T. granarium in comparison to a reference strain (Lab-TG) was determined against pirimiphos-methyl, permethrin and spinosad using dose-mortality bioassays. Based on lethal dose (LD50 and LD99) values, the Lab-TG strain was the most susceptible to all the insecticides in comparison to the field strains. In the case of field strains, LD50 values varied from: 17.68–31.97 mg/kg for pirimiphos-methyl, 20.50–42.47 mg/kg for permethrin, and 1.34–5.00 mg/kg for spinosad. Whereas LD99 values for pirimiphos-methyl, permethrin and spinosad of field strains varied from 409.07 to 730.24 mg/kg, 374.24–949.48 mg/kg, and 11.41–72.25 mg/kg, respectively. The resistance ratios (RR) at LD50 and LD99 levels were in the range of 13.71–24.78 and 39.33–70.21 fold for pirimiphos-methyl; 13.49–27.94 and 37.31–94.66 fold for permethrin; 2.35–8.77 and 3.37–21.31 fold for spinosad, respectively. Considering the overall results, spinosad proved to be the most toxic insecticide to the laboratory and field strains of T. granarium when compared with toxicity of pirimiphos-methyl or permethrin. Insecticidal bioassays implementing enzyme inhibitors revealed no effect on synergizing the toxicity of all the insecticides in the Lab-TG strain; however, enzyme inhibitors significantly synergized toxicity of pirimiphos-methyl in all the field strain suggesting the major involvement of metabolic mechanism associated with pirimiphos-methyl resistance. The study demonstrates variation in susceptibility to insecticides in T. granarium strains. The results might be helpful for monitoring future variation in susceptibility to insecticides in T. granarium and for setting field rates.

Variability of the Mandibular Sclerite and Its Value in Diagnostics of the Third Instar Larvae of the Mediterranean Fruit Fly Ceratitis capitata (Wiedemann, 1824) (Diptera, Tephritidae)

The Mediterranean fruit fly Ceratitis capitata (Wiedemann, 1824) is an important quarantine pest in the Eurasian Economic Union. The species is traditionally identified by morphological characters of the III instar larvae found in imported fruit products. In view of the existing discrepancies in the use of the mandibular sclerite characters in quarantine phytosanitary diagnostics of the III instar larvae of C. capitata, it is important to assess the intraspecific variability of this structure and to emend the identification keys accordingly. Analysis of microscopic preparations showed the morphometric parameters of mandibular sclerites to be highly variable in C. capitata. In particular, no correlation of these parameters with the geographic origin or host plants of the larvae was demonstrated in our material. Variability within the regional groups of samples exceeded the differences between the regions. Thus, data on the qualitative and quantitative variation of the mandibular sclerite in the III instar larvae, combined with the information on the invasive activity and the broad trophic spectrum in the Mediterranean fruit fly, indicate a wide reaction norm in this species.

Influence of climatic factors on the potential distribution of pest Heortia vitessoides Moore in China

Heortia vitessoides Moore is one of the predominant pests of Aquilaria sinensis (Lour.) Spreng, which is extremely harmful to this plant, and is also an important quarantine pest around the world. To understand the influence of climate factors on the distribution of this pest, maximum entropy modeling (MaxEnt) was used to predict the potential suitable distribution area under certain climatic conditions. The results showed that H. vitessoides was mainly located in the tropical and southern subtropical climate areas of China under current climatic conditions, with a total suitable distribution area of 107.48 × 104 km2. The highly suitable areas were concentrated in the Pearl River Basin and the south of Lancang River Basin with area of 46.19 × 104 km2. In the future, the suitable area showed a tendency to expand to the north. The total suitable distribution area of this species would reach 136.21 × 104-151.62 × 104 km2, which was 26.62%–40.65% higher than that of the current. The climatic factors of precipitation of warmest quarter, precipitation of wettest quarter, min temperature of coldest month, and mean temperature of warmest quarter were the dominant variables affecting the distribution of H. vitessoides. It can be seen that the suitable area of this pest is relatively large and tends to expand, which poses a threat to the growth of A. sinensis. It is suggested that the relevant afforestation and phytosanitary departments should attach great importance and take necessary measures to control the spread of this pest.

Dört Farklı Bitki Ekstraktının Patates Güvesi [(Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae)] Yumurta ve Larvasına Karşı Toksik Etki Çalışması

Bu çalışmada iki farklı kekik türü (Thymus vulgaris L. ve Origanum majorana L.), adaçayı (Salvia officinalis L.) ve Lavanta (Lavandula officinalis L.), bitki ekstraktının önemli bir karantina zararlısı olan Patatesten güvesi-PG [(Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae)]‘nin ergin öncesi dönemlerine karşı toksik etkisi araştırılmıştır. Her bir bitkinin ekstraktları üç farklı %3, 5 ve 10 ml/L‘luk konsantrasyonda etanol ile seyreltilmiş, zararlının larva ve yumurtalarına karşı uygulanmıştır. Yumurtaya uygulamada en yüksek konsantrasyonda (%10 ml/L) sırasıyla, lavanta ve T. vulgaris‘de %73,7, O. majorana'da %67,5 ve adaçayında ise %66,2 oranında inhibisyon gözlenmiştir. Elde edilen sonuçlar, konsantrasyon arttıkça, yumurta açılımının azaldığını gösterirken, en çok etki lavanta ve T. vulgaris‘in %10 ile muamele edilmiş P. operculella yumurtalarında görülmüştür. Gözlemler 7 gün boyunca yapılmıştır. Larva evresine karşı insektisit toksisite çalışmasında, 7. gün sonunda ölüm oranı en yüksek konsantrasyonda (%10 ml/L), O. majorana %91,2, Lavanta 90%, T. vulgaris %87 ve adaçayında %83,7 oranlarında tespit edilmiştir. Ayrıca larvada 4 farklı bitki ekstraktının konsantrasyonları arttıkça ölüm oranının da zamana bağlı olarak arttığı tespit edilmiştir. Sonuç olarak, bu çalışmada, bitki ekstraktlarının yumurta evresine ovisidal toksisitesi olduğu ve larva evresine de insektisidal etkisi olduğu bulunmuştur.

Full-Length Transcriptome Survey and Expression Analysis of Parasitoid Wasp Chouioia cunea upon Exposure to 1-Dodecene

Chouioia cunea (Yang) is an endoparasitic wasp which parasitizes pupae and thus plays an important role in the biological control of the fall webworm (Hyphantria cunea Drury), an important quarantine pest in the entire world and a major invasive pest in China. For the purposes of investigating which proteins are involved in the response of C. cunea to 1-Docecene, one of the chemical compounds of pupae of H. cunea with a significant attracting action to mated female C. cunea, 11.5 Gb transcriptome data was sequenced on the PacBio RS II platform from 1-day old C. cunea adults to generate a reference assembly. Afterwards, 46.88 Gb of clean RNA-Seq data were obtained to assess the transcriptional response of these insects before and after the stimulation with 1-Docecene. After removing redundancy using CD-HIT, a sequence structure analysis predicted 29,105 complete coding sequence (CDS) regions, 51,458 single-sequence repeats (SSRs), and 2,375 long non-coding RNAs. Based on the early transcriptome sequencing in our laboratory, we revealed some new sequences corresponding to chemosensory genes such as odorant binding proteins (OBPs), odorant receptor (OR), gustatory receptors(GRs). Results of quantitative real-time PCR experiments revealed that CcOBP7, CcOBP18, CcCSP4, CcOR2, and CcGR18 were up-regulated after 1-Dodecene stimulation. In addition, the expression of 31 genes, including 1 gene related to phospholipid biosynthesis and 2 genes related to transmembrane transport were up-regulated after 1-Dodecene stimulation; meanwhile, the expression of 22 genes, including 5 genes related to protein phosphorylation and protein serine/threonine kinase activity were significantly down-regulated after 1-Dodecene stimulation. These results suggest that the attraction of adult C. cunea to 1-dodecane is associated with the transmembrane signal transduction and dephosphorylation of some proteins. Our findings will provide useful targets for further studies on the molecular mechanism of host recognition in C. cunea.

Studies on potato cyst nematode (Globodera spp.) detection and soil health status in potato core area of Punjab, Pakistan

Potato (Solanum tuberosum) is considered as staple food and ranks fourth after wheat, rice and maize in Pakistan. Many biotic constraints affect potato production as potato cyst nematodes (Globodera spp.) are considered to be the most important quarantine pests of potato posing serious potential economic consequences throughout the world. Two hundred soil samples comprising of Okara, Sahiwal, Kasur and Pakpattan districts were analyzed by floatation technique at Plant Pathology Research Institute, Faisalabad and were found free from Potato Cyst Nematodes (PCN) infestation. Soil health study was also carried out following standard analytical techniques and soil health indicators for arable land like organic matter, extractable potash, available phosphorus and microbial populations were found in sufficient levels to ensure healthy crop production.

Biology and Control of the Khapra Beetle, Trogoderma granarium, a Major Quarantine Threat to Global Food Security.

The khapra beetle, Trogoderma granarium, is a voracious feeder of stored products and is considered one of the most important quarantine pests globally. Its ability to survive for long periods under extreme conditions facilitates its spread through international commerce, which has led to invasions of new geographic regions. The khapra beetle is an important quarantine pest for many countries, including the major wheat-producing countries the United States, Canada, Russia, and Australia, and has been classified as one of the 100 worst invasive species worldwide. This species cannot always be controlled by insecticides and other nonchemical methods that are usually effective against other pests of stored products, particularly owing to its diapausing late larval stage. It can rapidly develop at elevated temperatures and under dry conditions, which are not favorable for many major stored-product insects. We synthesize key published work to draw attention to advances in biology, detection and control of the khapra beetle, and directions to consider for future research.

Interaction Between Two Leafminer Parasitoids, Halticoptera arduine (Hymenoptera: Pteromalidae) and Diglyphus isaea (Hymenoptera: Eulophidae), in the Management of Liriomyza huidobrensis (Diptera: Agromyzidae).

Liriomyza spp., leafminer flies (Mik; Diptera: Agromyzidae), are economically important quarantine pests that puncture and mine leaves and fruits of various horticultural crops worldwide, affecting yield and trade. Halticoptera arduine (Walker; Hymenoptera: Pteromalidae), a key parasitoid from the pests' areas of origin in South America, was introduced as a potential alternative management strategy. Prior to H. arduine release, its potential interactions with the dominant local ectoparasitoid, Diglyphus isaea (Walker; Hymenoptera: Eulophidae), were assessed. Halticoptera arduine and D. isaea were released in single, sequential and simultaneous combinations on Liriomyza huidobrensis (Blanchard; Diptera: Agromyzidae) to evaluate possible effect on the parasitism rate, reproduction and host mortality. The combination of both parasitoids did not significantly affect the specific parasitism rates of either of them, an indication that H. arduine and D. isaea can coexist. Parasitism rates of the exotic H. arduine were significantly superior to the indigenous D. isaea in all release combinations except when both species were released simultaneously. While 50 individuals of D. isaea resulted only in 21.23 ± 2.1% parasitism, 50 parasitoids composed of 25 H. arduine and 25 D. isaea caused 53.27 ± 4.99%. Both parasitoids further induced significant nonreproductive host mortalities. Both parasitoids' F1 progenies sex ratios were female-biased in all parasitoid release combinations except in single release of D. isaea with a balanced sex ratio. The improvement in D. isaea's sex ratio induced by the presence of H. arduine suggests a synergetic effect on D. isaea's reproductive performance. The introduction of H. arduine in horticulture production systems may therefore improve natural control of Liriomyza leafminers in East Africa.

Afrina sporoboliae sp. n. (Nematoda: Anguinidae) Associated with Sporobolus cryptandrus from Idaho, United States: Phylogenetic Relationships and Population Structure.

The dropseed gall-forming nematode, Afrina sporoboliae sp. n., is described from seed galls of Sporobolus cryptandrus (Poaceae: Chloridoideae: Sporobolinae) collected in Idaho, USA. This is the third report of an Afrina species in North America and the first report of this genus in a natural plant population on this continent. Morphological, morphometric, and molecular analyses placed this nematode in genus Afrina and demonstrated that it differs from Afrina hyparrheniae and Afrina spermophaga by having longer body and stylet lengths for females and males, and from Afrina wevelli by the absence of tip irregularities on the tails of female and presence of lips noticeably protruding beyond the body contour. The new species has several characters that overlap with Afrina tumefaciens, but differs from this species by inducing seed galls, whereas Afrina tumefaciens induces ovoid galls on stems, leaves, and in flower heads. Evolutionary relationships of Afrina sporoboliae sp. n. with other representatives of the family Anguinidae are presented based on analysis of the internal transcribed spacer (ITS)1-5.8S-ITS2 rRNA and the D2-D3 regions of the rRNA genes. Analysis of 270 sequences of the cox1 gene from 25 populations of Afrina sporoboliae sp. n. revealed seven haplotypes with sequence divergence up to 5%. This study did not demonstrate a significant positive relationship between genetic difference and geographic distance. Seed gall nematodes are important quarantine pests in many countries. The association of this and other seed gall nematodes with Rathayibacter species and their ability to serve as vectors, especially of R. toxicus, is of concern for U.S. agriculture.

PM 7/28 (2) Synchytrium endobioticum

Specific scopeThis Standard describes a diagnostic protocol for Synchytrium endobioticum.This Standard should be used in conjunction with PM 7/76 Use of EPPO diagnostic protocols.Specific approval and amendmentApproved in 2003‐09. Revision approved in 2017‐06.

Development of a ‘lure and kill’ technique for apple leafcurling midge, <i>Dasineura mali</i>

Apple leafcurling midge (ALCM) is an important quarantine pest of New Zealand apples. Current methods for ALCM control have difficulty meeting the strict phytosanitary standards of some export markets. ‘Lure and kill’ is a new strategy against this pest, in which males are attracted to an insecticide-treated substrate where they collect a lethal dose. Trials were conducted using a gel matrix “Specialized Pheromone & Lure Application Technology” (SPLATâ„¢) to dispense and release the ALCM sex pheromone and the insecticide permethrin. Lures using SPLATâ„¢ were placed within plastic cylinder traps that collected the dead midges so they could be counted to determine treatment efficacy. The size, shape and age of SPLATâ„¢ spots influenced midge catches. Higher catches occurred with spots having a larger quantity of pheromone, greater surface area of SPLATâ„¢, or with fresh material. The implications for the development of a lure and kill strategy for ALCM are discussed.

Annual and regional variability in adult <i>Dasineura mali</i> (apple leafcurling midge) emergence in New Zealand

Apple leafcurling midge is an important quarantine pest for New Zealand apple exports. Season-long pheromone trapping was conducted in Hawke’s Bay and Nelson from 2004—2017, and from 2012—2017 in Central Otago. Four generations occurred annually in Hawke’s Bay and Nelson and 3—4 in Central Otago. In Hawke’s Bay and Nelson, the timing of each peak varied by about 3—4 weeks between years, while the difference was ~2—3 weeks in Central Otago during fewer years of monitoring. Hawke’s Bay was up to a month earlier than Central Otago for the same peak within individual years. The major factor behind this variability was the accumulated number of growing degree-days. Insecticide sprays target midge larvae, but are timed against the second and third peaks of adult emergence. Variations in the timing of these peaks annually and across the main pipfruit growing regions, mean that specific insecticide timing recommendations are necessary each year for each region.