Measuring the impact of Leptoglossus occidentalis (Heteroptera: Coreidae) on seed production in lodgepole pine using an antibody-based assay

We measured the impact of Leptoglossus occidentalis on seed production in lodgepole pine, Pinus contorta variety latifolia Engelmann, using an antibody marker developed to detect residual saliva in fed-on seeds. Nymphs, adult females, and adult males were caged on cones during early, mid- and late season cone development. Individual analysis of 12,887 seeds extracted from 365 cones revealed that 37.3% seeds tested positive for seed bug saliva. The antibody assay was 38 times more effective than radiography at detecting seed bug damage. Radiography can detect partially emptied seed but cannot discriminate between aborted seeds and those emptied by seed bugs. The antibody marker was least sensitive in detecting early season damage compared with mid- and late season damage. We hypothesize that residual saliva in seeds fed on early in the season was either absorbed by the damaged seed or degraded over time. Early season feeding resulted in the greatest number of seeds fused to cone scales and the extraction efficiency for cones exposed to feeding during this time was reduced by 64% compared with control cones. Adding fused seeds to antibody-positive seeds raised the proportion of damaged seeds to 48.3%. At all stages of cone development, adult females were the most destructive life stage, damaging up to two seeds per day late in the season. When seed losses were adjusted to damage per degree-day, female damage was greatest early in the season, while males caused the same amount of damage regardless of cone development period. The results of the antibody assay provide baseline data for developing damage prediction formulae, and establish L. occidentalis as a potentially serious pest in lodgepole pine seed orchards.     

Distribution analysis of Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae) in South Korea using climate and host plant ensemble maps

Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae) is a notorious pest that causes irreversible damage to coniferous forests in South Korea. However, an effective control strategy is still under development. In this study, we used CLIMEX to analyze the potential distribution of L. occidentalis in relation to climate and host plants in South Korea for the identification of effective control spots. The climate needs of L. occidentalis under current and future climate conditions were analyzed and projected on a map along with the distribution of coniferous forests. The CLIMEX model projected that the area of L. occidentalis distribution would decrease slightly in 2060 compared with that at present. However, it was projected that occurrence in mountainous regions would be sustained, suggesting continued damage to coniferous forests in South Korea.     

Scent gland apparatus in the Western conifer seed bug Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae)

The coreid Leptoglossus occidentalis is a Nearctic bug responsible for severe seed losses to pine orchards. When disturbed, adults and nymphs emit a defensive secretion deemed an allomone. Here we describe the gross morphology of the scent gland apparatus and the related evaporatory structures in nymphs and adults of L. occidentalis, through light microscopy and scanning electron microscopy. Adults of both sexes possess a metathoracic scent gland complex (MTG) including a central orange‐yellow reservoir and a pair of white lateral glands, connected by ducts to the reservoir. The MTG belongs to the diastomian type, with two ostioles located on the metathorax associated with a microsculptured cuticular accumulation area, i.e. evaporatory area, which can prevent the spread of the secretion on to non‐evaporative cuticle and increase scent fluid evaporation. A high number of male‐specific sternal gland pores were observed. These pores and associated glands are likely the source of an attractant pheromone, which could be extremely useful in monitoring and combating this invasive pest. In nymphs, MTG is replaced by two dorsal abdominal scent glands (DAGs) located between the 4th and the 6th urotergites. DAGs are reddish cuticle‐lined sacs with gland cells forming the gland wall; the scent substances are released through two orifices lying on the mid‐dorsal abdominal line between urotergites IV–V and V–VI. Also in nymphs, peculiar cuticular evaporatory areas surround both orifices.     

Specific biochemical marker-based techniques for the identification of damage to Douglas-fir seed resulting from feeding by the western conifer seed bug, Leptoglossus occidentalis Heidemann (Hemiptera: Coreidae)

Specific biochemical marker-based techniques were tested for their ability to distinguish between seeds of Douglas-fir, Pseudotsuga menziesii (Mirbel) Franco, that were filled or unfilled (aborted) at maturity and those that were damaged or emptied by the western conifer seed bug, Leptoglossus occidentalis Heidemann. A polyclonal antibody raised against salivary gland extracts from L. occidentalis successfully identified residual salivary proteins on Western blots containing proteins from Douglas-fir seeds that had sustained various degrees of seed bug feeding damage. In a single blind experiment, the polyclonal antibody correctly identified 100% of undamaged control, 97% of unfilled control (aborted), and 98% of seed bug damaged seeds. Polyclonal antibodies raised against insoluble alfalfa crystalloid storage protein (11S globulin) detected the depletion of 11S globulin and the subsequent appearance of its hydrolyzed fragments in the soluble protein fraction of Douglas-fir seeds that were fed-upon by the seed bug. Feeding by L. occidentalis nymphs caused ca. 98% depletion of insoluble protein, but only ca. 53% reduction in the amount of soluble protein in seeds that appeared empty on radiographs. By comparison, unfilled (aborted) seeds contained significantly less insoluble and soluble protein than empty seeds that were fed-upon by L. occidentalis; moreover, no crystalloid (11S globulin) breakdown products were generated. The biochemical markers described in this study are reliable tools that can be used to identify conifer seeds that have sustained light to severe damage from L. occidentalis feeding.     

Morphological and biological characteristics of the Korean population of Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae), an invasive insect pest of conifer cones

In this study, we investigated the morphological and biological characteristics of a serious insect pest of conifer cones, the western conifer seed bug (WCSB), Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae), in Korea. WCSB adults shared external morphology with overseas populations, including zig-zag fascia on the coria, dilation of the hind tibiae, and color pattern on the abdominal dorsum. The average body length and width of WCSB adults were 17.20 and 4.85 mm, respectively, in males and 19.05 and 5.55 mm in females. The average body weights were 111.27 and 169.89 mg in adult males and females, respectively. On average, eggs were 2.12 mm long and 1.17 mm wide. The average body lengths of the first- to fifth-instar nymphs were 3.07, 4.76, 8.77, 13.56, and 15.53 mm, respectively. For biological characteristics, developmental durations of the egg and five nymphal instar stages were 8.6, 3.7, 7.6, 5.8, 5.8, and 9.1 days, respectively, in laboratory conditions. Nymphal mortality was 47.5% in total. The average life expectancy of WCSB adults was 58.2 and 63.9 days in males and females, respectively. Oviposition of the adult females started 23.4 days after emergence, and the total number of eggs laid by a single adult female was 68.6 on average. The results of this study offer basic morphological and biological information that can be used to design an effective control strategy to manage the WCSB population in Korea.     

Functional anatomy of the vagina muscles in the adult western conifer seed bug,Leptoglossus occidentalis (Heteroptera: Coreidae), and its implication for the egg laying behaviour in insects

The anatomy of the female reproductive tract and the nerve-evoked contractions of the vagina muscles and their association with the ovipositor in the western conifer seed bug, Leptoglossus occidentalis (Heidemann) are investigated for the first time. The reproductive tract consists of a set of paired telotrophic ovaries, each containing seven ovarioles, located in the anterior lateral regions of the abdomen. Each ovary is attached to a lateral oviduct which spans most of the abdomen to attach to a relatively short common oviduct that joins the vagina near the rear of the animal. The vagina is associated with a pair of bilaterally symmetrical muscles attached at their posterior ends to lateral extensions of sternite VIII, the valvifer of the Type II ovipositor. From this attachment site, the muscles fan out medially and anteriorly to converge along the dorsal midline of the vagina up to the base of the common oviduct. Vagina muscles respond to a single stimulation of their motor nerves by producing a smooth contraction lasting approximately 1 s. With increasing frequencies of stimulation, the muscle contractions summate to create a tetanic response. The muscles are fatigue resistant being able to maintain the same degree of tension for up to 10 min at 10 Hz stimulation. Visual observation shows that other muscles associated with the valves of the ovipositor behave in a similar fashion to that of the vagina muscles from which the tension recordings were obtained. Fatigue-resistant vagina muscles are discussed in relation to copulation, sperm transport and this insect's ability to deposit a series of eggs directly onto the surface of a conifer needle in a manner by which eight or more blunt-ended eggs are packed end-to-end in a single row.     

Functional morphology of the hind legs as weapons for male contests inLeptoglossus australis (Heteroptera: Coreidae)

Functional morphology of the hind legs as weapons in male contests was analyzed in the leaf-footed plant bug, Leptoglossus australis Fabricius. Measurement of some metrical tratis of the hind femur and tibia indicated that the weapon was the hind femur. Sexual dimorphism in the femoral length and width, and in the number of spines on the lower side of the femur, indicated that these parts play a significant role in male contests. It was also suggested that the length from the base to the widest part of the femur had a functional significance for male-male combat behaviors ofL. australis.     

Predators and competitors of the mountain pine beetle Dendroctonus ponderosae (Coleoptera: Curculionidae) in stands of changing forest composition associated with elevation

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高温对西花蓟马卵巢发育及卵黄蛋白含量的影响

【目的】为探明短时高温热激后西花蓟马 Frankliniella occidentalis (Pergande)生殖力和卵巢发育的相互关系。【方法】选择1龄、2龄若虫,预蛹,蛹和1日龄成虫,采用不同高温（41和45℃）短时（2 h）处理,观察卵巢发育及卵黄蛋白相对含量的变化。【结果】高温热激主要抑制了西花蓟马生殖器官和胚胎的正常发育,导致卵巢管数量减少,卵巢管和胚胎发育畸形;电泳结合不同的染色方法证明西花蓟马的卵黄蛋白为一种磷酸化、糖基化的脂蛋白,由3个亚基组成,分子量分别为116,70和47 kDa。除热激蛹期外,热激其他龄期的若虫对其当代成虫卵黄蛋白合成都起到抑制作用,且45℃热激1龄或2龄若虫后,其对卵黄蛋白相对含量的影响持续到了F₁代。【结论】温度对雌虫生殖力的影响是由于其对生殖器官发育和卵黄蛋白合成的影响引起的。本研究为西花蓟马的卵黄蛋白和卵黄发生的进一步研究奠定了基础。     

Glacial vicariance in the Pacific Northwest: evidence from a lodgepole pine mitochondrial DNA minisatellite for multiple genetically distinct and widely separated refugia

The Canadian side of the Pacific Northwest was almost entirely covered by ice during the last glacial maximum, which has induced vicariance and genetic population structure for several plant and animal taxa. Lodgepole pine ( Pinus contorta Dougl. ex. Loud.) has a wide latitudinal and longitudinal distribution in the Pacific Northwest. Our main objective was to identify relictual signatures of glacial vicariance in the population structure of the species and search for evidence of distinct glacial refugia in the Pacific Northwest. A maternally inherited mitochondrial DNA minisatellite-like marker was used to decipher haplotype diversity in 91 populations of lodgepole pine located across the natural range. Overall population differentiation was sizeable ( G _ST = 0.365 and R _ST = 0.568). Four relatively homogeneous groups of populations, possibly representative of as many genetically distinct glacial populations, were identified for the two main subspecies, ssp. latifolia and ssp. contorta . For ssp. contorta , one glacial lineage is suggested to have been located at high latitudes and possibly off the coast of mainland British Columbia (BC), while the other is considered to have been located south of the ice sheet along the Pacific coast. For ssp. latifolia , two genetically distinct glacial populations probably occurred south of the ice sheet: in the area bounded by the Cascades and Rocky Mountains ranges, and on the eastern side of the Rockies. A possible fifth refugium located in the Yukon may have also been present for ssp. latifolia . Zones of contact between these ancestral lineages were also apparent in interior and northern BC. These results indicate the role of the Queen Charlotte Islands and the Alexander Archipelago as a refugial zone for some Pacific Northwest species and the vicariant role played by the Cascades and the American Rocky Mountains during glaciation.     

Use of pityol to reduce damage by the white pine cone beetle, Conophthorus coniperda (Col., Scolytidae) in seed orchards

Abstract:  The white pine cone beetle, Conophthorus coniperda (Schwarz), is a common and destructive pest of eastern white pine cones. The potential of mating disruption as a pest management tool against C. coniperda was tested during this experiment. The 5.5 ha white pine seed orchard used in this study was separated in three equal sections and different blocks were treated with pityol over 2-year experiments. Ten and 20 pityol dispensers (bubble caps) were hung per treated block in 2001 (east block) and 2002 (centre block), respectively, to evaluate their impact on cone protection. During both seasons, the percentage of damaged cones at permanent stations was evaluated at monthly intervals in the middle of the treated block and at different places in the control area. For both years, the mean reduction in cone damage was 63.7% in the pheromone-treated blocks. With this study, we have been able to demonstrate that mating disruption could be used as a biological pest management tool for the control of C. coniperda in white pine seed orchards.     

二种活体饲料对东亚小花蝽生长发育和生殖的影响

本文比较了果蝇Drosophila melanogaster(Meigen)幼虫和西花蓟马Frankliniella occidentalis(Pergande)2种活体饲料对东亚小花蝽Orius sauteri(Poppius)生长发育和生殖的影响。结果显示:果蝇幼虫饲喂的东亚小花蝽幼虫发育历期12.36d,与西花蓟马饲喂的(12.19d)相近。果蝇幼虫饲喂的东亚小花蝽产卵量(89.58粒)与西花蓟马饲喂(95.72粒)相当。表明果蝇幼虫与传统活体饲料西花蓟马饲养东亚小花蝽的效果相当,可以很好的满足东亚小花蝽生长发育和生殖的要求。由于西花蓟马饲喂成本比较高,实际操作中有一定困难,果蝇幼虫是一种较为理想的活体饲料。     

First records of the western conifer seed bug Leptoglossus occidentalis Heid. (Heteroptera, Coreidae) from Russia and Ukraine, regularities in its distribution and possibilities of its range expansion in the palaearctic region

The paper presents the first records of the western conifer seed bug Leptoglossus occidentalis Heidemann, 1910 for the fauna of Russia (Rostov Province) and Ukraine (Crimea and Zaporizhia Province). The dependence of the spread of this species on positive and negative temperatures and the availability of food plants is considered. The forecast of further expansion of its range in the Palaearctic Region is given.     

Performance of the predator Amblyseius swirskii (Acari: Phytoseiidae) on greenhouse eggplants in the absence and presence of pine Pinus brutia (Pinales:Pinaceae) pollen

In Turkey, the western thrips Frankliniella occidentalis (Pergande) is a key pest affecting eggplants grown in greenhouses for which an appropriate control strategy is under investigation. It was observed in a previous study that the release of the beneficial predatory mite Amblyseius swirskii (Athias‐Henriot) alone did not result in an effective control of thrips on eggplants. Since pollen is known to improve control efficiency of predators, this study was undertaken to investigate if provision of pollen to eggplants can greatly improve the efficiency of A. swirskii in controlling thrips. The experiments were carried out in both greenhouse and low tunnel. The provision of pollen led to a significant increase in the predator population density on the eggplants but did not result in an effective control of the thrips populations. In this paper, various factors are discussed that could have affected the efficiency of the predatory mite in controlling F. occidentalis on eggplants.     

高温和啶虫脒处理西花蓟马对其F1 代生命表参数的联合作用

【目的】西花蓟马 Frankliniella occidentalis (Pergande) (缨翅目: 蓟马科）是一种危险的入侵害虫,其生长发育受温度影响显著。我们的前期研究表明,高温热激对西花蓟马的杀灭效果并不理想,但高温热激可以改变西花蓟马的药剂敏感性。为了探究高温热激后再进行杀虫剂减量处理能否提高高温对西花蓟马的防治效果,本实验测定了45℃高温热激 2 h后恢复不同时间（8 h 和24 h）啶虫脒对西花蓟马F₁代生命表参数的影响,从控制种群发展的角度探究高温和啶虫脒防治西花蓟马最佳结合方式。【方法】应用特定年龄 龄期及两性生命表的方法,研究45℃高温热激和啶虫脒处理西花蓟马后其F₁代种群的生命表参数。【结果】45℃热激2 h后恢复不同时间用啶虫脒处理西花蓟马亲代,其F₁代卵、1龄幼虫和蛹的平均发育历期均显著长于对照（仅45℃热激2 h）的西花蓟马F₁代（P<0.01）;而且其F₁代雌成虫的寿命和产卵量均显著少于对照（P<0.01）。热激恢复8 h后啶虫脒处理西花蓟马亲代,其F₁代发育历期和雌成虫的寿命虽然与热激恢复24 h的F₁代不存在显著性差异,但是其F₁代的平均产卵前期（adult pre-oviposition period, APOP）和平均总产卵前期（total pre-oviposition period, TPOP）显著长于恢复24 h的F₁代（P<0.01）,单雌平均产卵量显著小于恢复24 h的F₁代（P<0.01）。【结论】相比单一高温防治,高温和杀虫剂综合使用对西花蓟马有更好的防控效果。相比热激后恢复24 h,热激后恢复8 h再进行杀虫剂处理对西花蓟马有更好的防控效果。     

Effects of green tree retention, prescribed burning and soil treatment on pine weevil (Hylobius abietis and Hylobius pinastri) damage to planted Scots pine seedlings

1 Feeding damage and mortality caused to planted Scots pine seedlings by the pine weevils Hylobius abietis and Hylobius pinastri were studied on burned and unburned sites with 0, 10 and 50 m³ per hectare levels of green tree retention from the second to the fourth summer after logging and burning of the sites. 2 The rate of severe feeding damage to pine seedlings caused by pine weevils was higher on burned clearcut sites than on unburned ones, whereas burning did not increase the feeding damage rate on sites with groups of retention trees. The damage rate in the fourth summer was approximately the same on burned and unburned sites. 3 Pine weevil feeding was the major cause of mortality of freshly planted pine seedlings on unburned sites. On burned sites, mortality was higher than the rate of severe feeding damage, particularly in the second summer after burning, possibly owing to fungal attack and abiotic factors. 4 At a retention tree level of 50 m³, feeding damage to the seedlings was lower than on clearcuts and at a 10 m³ retention tree level. Furthermore, on sites with 50 m³ of retention trees, scarification of the soil was found to decrease feeding damage more effectively than on clearcuts and 10 m³ sites. If the seedlings were situated in the centre of scarified patches, scarification alone was as effective as insecticide treatment on unscarified soil for decreasing feeding damage and mortality. 5 The results suggest that when burning is applied as silvicultural treatment after clear‐cuts, retention of trees is recommended to reduce the damages caused by pine weevils on pine seedlings.     

Chloroplast phylogeography and evolution of highly polymorphic microsatellites in lodgepole pine ( Pinus contorta)

We employed a novel set of six highly polymophic chloroplastic simple sequence repeat (cpSSR) loci to investigate the phylogeography of lodgepole pine (Pinus contorta Dougl. Ex. Loud.), and to examine aspects of the evolutionary process operating on these repetitive DNA sequences. Chloroplast haplotypes of 500 trees, sampled throughout the range of lodgepole pine, were determined. We found a marked association of genetic distance with physical distance within the scale of 0 to 1,000 km, but no association beyond that range. Likewise, geographic clustering was observed only among recent clades in a dendrogram. These phylogeographic patterns are consistant with a rapid rangewide expansion (”big-bang”) followed by recent, local population differentiation (”galaxy formation”). In support of this expansion, coalescent simulations of the genealogical process gave a long-term effective population size in the low thousands, and a time to common ancestry of about 1,500 generations (12,000 years), consistent with a post-Pleistocene population expansion as documented by previous pollen-sediment analyses. Two lines of evidence (mapping mutational events onto a phylogeny, and evaluation of observed versus expected gene diversity) suggest that five of the cpSSR loci evolve primarily by a stepwise model of evolution of single repeat changes (but with a small proportion of changes involving two or more repeats), and the coalescent simulations point to a mutation rate of about 10^–3. Received: 7 December 2000 / Accepted: 17 May 2001     

长白山阔叶红松(Pinus koraiensis)林种子雨组成及其季节动态

为了解阔叶红松(Pinus koraiensis)林的种子雨组成及其在时间和空间上的动态变化,在长白山阔叶红松林25 hm2样地内,设置了150个种子收集器,收集掉落于种子收集器中的果实、种子等.所有收集到的样品分别鉴定其种类并分为成熟种实、未成熟种实、花序和果实或种子碎片及其附属物4类,计算各类别的数量,而后分别烘干秤重.从2005年6月到2006年11月,共收集到隶属11科12属20种的种实及其生殖器官残体.累计收集到121291粒种实,其中成熟种实23147粒,仅占所有种实总个体数的19.1%.种实数最多的树种是紫椴(Tilia amurensis)和水曲柳(Fraxinus mandshurica),两个树种种实的个体数占总个体数的90%.对2006年5月～11月种子雨季节动态的分析发现:种实在7月中旬至10月下旬数量极大,但主要由未成熟种实组成;在10月中旬出现成熟种实散落高峰,但未成熟种实仍占一定的比例.按每个收集器收集到的成熟种实数统计,成熟种实数量在100～200之间的收集器数量最多.按每个收集器收集到的树种数统计,收集器中最多收到的树种数为7,树种数为3和4的收集器个数最多.对6个主要树种成熟种实所在收集器的空间分布进行分析发现,紫椴和水曲柳的成熟种实在整个样地都有分布,春榆(Ulmus japonica)、糠椴(T. mandshurica)、色木槭(Acer mono)和假色槭(A. pseudo-sieboldianum)则只在样地的局部区域收集到成熟种实.成熟种实的空间分布与母树的空间分布大都表现出明显的相关性,表明这些树种的成熟种实并没有扩散到离母树较远的距离.     

Composition and seasonal dynamics of seed rain in broad-leaved Korean pine (Pinus koraiensis) mixed forest in Changbai Mountain, China

To explore the composition and spatio-temporal dynamics of seed rain in broad-leaved Korean pine (Pinus koraiensis) mixed forest, 150 seed traps were set up in a 25 hm2 plot in Changbai Mountain. Seeds, fruits, anthotaxy and others in seed traps were collected, identified and divided into 4 types. From 2005 to 2006, we collected 47 different types. Total number of seeds and fruits was 121291, including 23147 mature seeds and fruits (19.1% of the total). Tilia amurensis and Fraxinus mandshurica, with the most seeds and fruits, accounted for 90% of the total. The analysis on seasonal dynamics of seed rain showed that there were the largest number of seeds and fruits between July and October, which were composed of immature seeds and fruits. In mid-October, mature seeds and fruits reached their peak, but immature seeds and fruits still accounted for high proportion. There were 91 traps that contained 100–200 mature seeds and fruits, and one trap without any mature seed or fruit. The largest number of species found in a trap was 7, and usually 3 or 4 species were found in most of the traps. There were obvious relationships between spatial patterns of mature seeds and fruits and their parent trees, indicating that their mature seeds and fruits were not dispersed far from their parent trees.