[Spectroscopic Studies on the Host Plant Selection Mechanism of Trabala vishnou gigantina Yang (Lepidoptera: Lasiocampidae)].

Trabala vishnou gigantina Yang (Lepidoptera: Lasiocampidae) is a polyphagous forestry pest whose periodic breaking out results in great economic damage including total crop failure to forestry and fruit production in China. In this study, in order to improve the understanding of the host plant selection mechanism of T. vishnou gigantina larvae, locust, caragana, willow, poplar, apricot and sea-buckthorn were used as potential host plants for the test. Two-way choice experiment method was used to study the T. vishnou gigantina Yang feeding preferences of the six kinds of plants. Moreover, the chemical component and physical structure of six plants were analyzed with Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). Among the six plants, T. vishnou gigantina larvae showed a strong preference for sea-buckthorn, followed by, apricot, willow, poplar, locust, and caragana. The FTIR analysis displayed that those six plants presented similar characteristic on absorption peak position, peak amount, and shape. The targets (1 154/1 733, 1 154/898) by FTIR showed that lipids and polysaccharide were major nutriments to affect the host plant selection of T. vishnou gigantina larvae. The XRD results showed that crystallinity index (CrI) also could affect the host plant selection of T. vishnou gigantina larvae. In this research, spectroscopy technology was firstly applied to the study of interactive relationship between insect and host, which would blaze a trail for intensive study of host plant selection mechanism of insect at molecular level.

Quantitative classification and environmental interpretation of secondary forests 18 years after the invasion of pine forests by Bursaphelenchus xylophilus (Nematoda: Aphelenchoididae) in China.

With growing concerns over the serious ecological problems in pine forests (Pinus massoniana, P. thunbergii) caused by the invasion of Bursaphelenchus xylophilus (the pine wood nematode), a particular challenge is to determine the succession and restoration of damaged pine forests in Asia. We used two-way indicator species analysis and canonical correlation analysis for the hierarchical classification of existing secondary forests that have been restored since the invasion of B. xylophilus 18 years ago. Biserial correlation analysis was used to relate the spatial distribution of species to environmental factors. After 18 years of natural recovery, the original pine forest had evolved into seven types of secondary forest. Seven environmental factors, namely soil depth, humus depth, soil pH, aspect, slope position, bare rock ratio, and distance to the sea, were significantly correlated with species distribution. Furthermore, we proposed specific reform measures and suggestions for the different types of secondary forest formed after the damage and identified the factors driving the various forms of restoration. These results suggest that it is possible to predict the restoration paths of damaged pine forests, which would reduce the negative impact of B. xylophilus invasions.

Impact of temperature on postdiapause and diapause of the Asian gypsy moth, Lymantria dispar asiatica.

Lymantria dispar asiatica (Vnukovskij) (Lepidoptera: Lymantridae) is one of three gypsy moth subspecies found in East Asia. Understanding the diapause and postdiapause phases of its eggs is important in characterizing its life cycle. The effects of different constant temperatures for different lengths of times on field-collected, postdiapause eggs were tested during the first year. In the second year, the effects of the same treatments on laboratory-raised eggs in diapause were investigated. The effects of temperature on percent egg hatching, time to hatching, and hatching duration were determined. When field-collected eggs were held at 0 and 5°C, they terminated postdiapause within 11 days. The percent hatching tended to decline with an increased duration of exposure at temperatures greater than 5°C. Diapause terminated slowly (> 37 days) and with a high percentage of hatching for postdiapause eggs held at 10°C. There was a positive correlation between temperature and the speed of postdiapause development for field-collected eggs held at constant temperatures between 10 and 25°C. However, the number of days to the first hatch was significantly longer than for eggs treated with lower temperatures before being transferred to 25°C. Freshly oviposited eggs treated at a constant 0 or 5°C for 200 days were unable to develop into pharate larva. However, eggs treated at a constant 20 or 25°C for 200 days developed into pharate larva but did not hatch even after a subsequent chill. This result suggests why L. dispar asiatica is not found in tropical areas and helps us to predict the distribution of the gypsy moth in China.

First report of Endoclita signifer (Lepidoptera: Hepialidae) as a new pest on Eucalyptus.

Endoclita signifier Walker (Lepidoptera: Hepialidae) has become a new wood borer pest in Eucalyptus plantations in southern China. This article documents survey results of its geographic distribution and host plant range in Guangxi and its morphological measurements, life cycle and behavior. In total, 83 Eucalyptus growing counties were surveyed. E. signifier was found in 59 counties. Host plants included 31 species in 16 families and 24 genera. Four Eucalyptus hybrid species were recorded as its host plant with E. grandis x E. urophylla and E. urophylla x E. grandis infested the heaviest. The infestation of Eucalyptus trees 1-2 yr old was heavier than that of older trees. Most individuals of E. signifier took 1 yr to complete a generation, overwintering as larvae in tunnels in wooden stems, and pupating in February of the following year. Adults emerge, mate, and lay eggs in April, and the eggs hatch in late April or early May. Adult emergence peaks between 17:00-18:59 hours. Mating flights last under 30 min at dusk and the copulation duration was 24 h. Moths were large, weighting and average of 3.4 g. Eggs and newly hatched larvae were very small, weighing only 0.127 +/- 0.001 mg and 0.093 +/- 0.017 mg, respectively. The larvae have two distinct development stages. One stage spends 1-2 mo living in the forest litter, the second stage then moves to woody stems where it feeds for approximately 10 mo. Larvae start boring into hosts between June and November, mainly in July and August. This study indicated that E. signifier, a highly polyphagous native species, has shifted host to exotic Eucalyptus and can cause significant damage to plantations.

Female sex pheromone blends and male response of the legume pod borer, Maruca vitrata (Lepidoptera: Crambidae), in two populations of mainland China.

The legume pod borer, Maruca vitrata (Lepidoptera: Crambidae; syn. M. testulalis), is a serious pantropical insect pest of grain legumes. Comparative studies of M. vitrata female sex pheromone components in two different geographic populations in China, Wuhan and Huazhou, confirmed that (E,E)-10,12-hexadecadienal (E10,E12-16:Ald) and (E)-10-hexadecenal (E10-16:Ald) were present in variable ratios in all pheromone gland extracts of both populations. (E,E)-10,12-hexadecadienol (E10,E12-16:OH) was always detected in minor amounts using polar DB-WAX columns, but was never detected using medium-polar DB-17 columns for the two populations. E10-16:OH was not found in any of the M. vitrata sex pheromone gland extracts. The average ratios of E10-16:Ald, E10,E12-16:Ald, and E10,E12-16:OH in the pheromone gland extracts of populations from Wuhan and Huazhou were 79.5:100:12.1 and 10.3:100:0.7, respectively. Electrophysiological testing suggested that E10,E12-16:Ald elicited the highest male electroantennography (EAG) response, followed by E10,E12-16:OH and E10-16:Ald. Field-trapping tests with single synthetic sex pheromone lures showed that E10,E12-16:OH alone could not attract males, whereas E10,E12-16:Ald or E10-16:Ald alone attracted few males. Wuhan and Huazhou males were most attracted by lures containing E10-16:Ald + E10,E12-16:Ald + E10,E12-16:OH in doses of (80 + 100 + 10) microg and (10 + 100 + 10) microg, respectively, per vial. Males could discriminate between the blends that were most attractive to their own geographic population and those that were most attractive to the reference population. Our findings suggest that geographic variation exists in the sex pheromone system of M. vitrata in China. The results are discussed with regard to the mechanisms underlying the sex pheromone variation.

Parasitoids of the sawfly, Arge pullata, in the Shennongjia National Nature Reserve.

Larvae of the argid sawfly, Arge pullata (Zaddach) (Hymenoptera: Argidae), feeds on leaves of birch (Betula spp.) in China, Europe, Siberia, and Japan. Parasitoids of A. pullata were studied in Shennongjia National Nature Reserve, Hubei Province, China, in 2009 and 2010. Five parasitoid species were found: Pleolophus suigensis (Uchida), Mastrus nigrus Sheng, Endasys parviventris nipponicus (Uchida) (Hymenoptera: Ichneumonidae), Vibrissina turrita (Meigen) (Diptera: Tachinidae) and Conura xanthostigma (Dalman) (Hymenoptera: Chalcididae). The average parasitism rate of A. pullata by parasitoids was as high as 11.0%. V. turrita was the dominant species, attacking 10.0% of the A. pullata cocoons. The emergence peak of V. turrita was from late May to early June. Three hyperparasitoids of V. turrita emerged from cocoons of A. pullata: Mesochorus ichneutese Uchida (Hymenoptera: Ichneumonidae), Pediobius sp. (Hymenoptera: Eulophidae), and Taeniogonalos maga (Teranishi) (Hymenoptera: Trigonalidae). Hyperparasitism rates were about 1.0% to 3.0%, with an average rate of 1.7%.

Lissonota holcocerica Sheng sp.n (Hymenoptera: Ichneumonidae) parasitizing Holcocerus hippophaecolus (Lepidoptera: Cossidae) from China.

This paper describes Lissonota holcocerica Sheng sp.n. (Hymenoptera: Ichneumonidae), parasitizing Holcocerus hippophaecolus Hua, Chou, Fang and Chen (Lepidoptera: Cossidae) in Inner Mongolia, Liaoning, and Ningxia, China. The adults of L. holcocerica emerge from a cocoon during the daytime, mostly from 09:00 to 14:00 hr, then start calling and mating, mostly from 08:00 to 12:00 hr. Mating lasts from 15 sec to 15 min. The longevity of males is 5.8 ± 2.4 days, whereas for females longevity is 7.6 ± 4.6 days in the field. Nutritional supplements can significantly extend the life span of L. holcocerica. Mated females search for hosts by walking on the base of Hippophae rhamnoides L. (Rosales: Elaeagnaceae) stem infested by Ho. hippophaecolus, vibrating their antennae and tapping while searching the stem for oviposition sites. Parasitized cocoons of Ho. hippophaecolus collected in field were half the size of normal ones or even smaller.

[Changes of reflectance spectra of pine needles in different stage after being infected by pine wood nematode].

In the present study, seedlings of Pinus Thunbergii and Pinus Massoniana were planted and used for reflectance spectrum measurement. In different stage after being infected by pine wood nematode, reflectance spectra were measured by ASD spectrometer and the features of spectral parameters and the change of chlorophyll were analyzed. The results showed that (1) Disease could be estimated in the early stage according to the curve of mid-infrared reflectance; (2) Dynamic parameters such as the position of red edge, green peak height, reflectance of red band, slope of red edge and reflectance of water-stressed wave band were consistent with the disease features of two pine species after being infected by pine wood nematode; (3) To both of two pine species, content of chlorophyll tended to reduce with the development of disease and obvious linear relationship was observed between chlorophyll content and spectral parameters. There results might be able to provide some theoretical basis for the application of remote sensing technology in monitoring of pine wood disease. In addition, it might be also used as theoretical support for the controlling measures in different stage after being infected by pine wood nematode.

The species of Rhimphoctona (Xylophylax) (Hymenoptera: Ichneumonidae: Campopleginae) parasitizing woodborers in China.

Four species of Rhimphoctona (Xylophylax) collected from P. R. China are reported. Two of them are new to science: Rhimphoctona (Xylophylax) maculifemoralis Luo and Sheng, sp.nov. reared from Tetropium castaneum (Linnaeus), and Rhimphoctona (Xylophylax) immaculata Luo and Sheng, sp.nov. One is a new record for China, R. (Xylophylax) rufocoxalis ( Clément 1924 ) reared from T. castaneum (Linnaeus). The other is R. (Xylophylax) lucida ( Clément 1924 ) reared from Monochamus saltuarius Gebier, Tetropium gabrieli Weise and Asemus sp. A key to species known in China is provided.

Effects of endophytic fungi in Mongolian pine on the selection behavior of woodwasp (Sirex noctilio) and the growth of its fungal symbiont.

BACKGROUND: The European woodwasp, Sirex noctilio, is a global invasive pest, attacking a wide variety of pine species by inoculating spores of a symbiotic fungus (Amylostereum areolatum) at oviposition. The woodwasp larvae depend on the growth of the symbiotic fungus to feed. The relationship among host endophytic fungi, symbiotic fungus and woodwasp remain elusive. Here, the effects of endophytes in Mongolian pine on the growth of Amylostereum areolatum and the selection behavior of female woodwasp were investigated by quantifying the mycelium growth rates and olfactometry assays. RESULTS: The endophytic plant fungi, Trichoderma harzianum, Phlebiopsis gigantea, T. viride and T. atroviride, completely killed the mycelia of Amylostereum areolatum. Mycelium fermentation broth of Chaetomium globosum inhibited the growth of the symbiont. Moreover, we observed that volatiles of Ophiostoma minus and Aspergillus niger (acetophenone, acetylacetone, hexadecane, phenylethyl alcohol, and isopropyl myristate) had repellent effects on adult female woodwasp. While volatiles of Amylostereum areolatum ((-)-globulol, 2-hexene, cycloprop[e]indene-1a,2(1H)-dicarboxaldehyde, terpene and cyclopentanone) had a significant attractiveness to adult female woodwasp. CONCLUSIONS: Some species of the host endophytic fungi had a significant negative effect on the growth and development of woodwasps, which could be useful in the monitoring and effective management of woodwasps. © 2018 Society of Chemical Industry.

Ultrastructure and distribution of sensilla on the maxillary and labial palps of Chlorophorus caragana (Coleoptera: Cerambycidae).

Chlorophorus caragana is a species of long-horned beetle that damages Caragana davazamcii Sancz. (Fabales: Papilionaceae) bushes in desert areas in China. The beetles cause substantial damage to local forestry plantations and the environment. Sensilla on the maxillary and labial palps of coleopterans a allow the insects to recognize their host plants. We used scanning and transmission electron microscopy to study the ultrastructure, distribution, and abundance of various sensilla on the maxillary and labial palps of C. caragana. We found four types of sensilla including ten subtypes: one of Böhm's bristles, three of sensilla chaetica, one of digitiform sensilla, and five of sensilla twig basiconica. The types and distribution of the sensilla on the maxillary and labial palps were highly similar between males and females. Finally, this article discusses the functions of the sensilla of related species in recognizing hosts and the significance of gustation studies in the context of the control of C. caragana.

EAG response and behavioral orientation of Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae) to synthetic host-associated volatiles.

Dastarcus helophoroides Fairmaire (Coleoptera: Bothrideridae) is an effective predatory beetle of larvae and pupae of several cerambycid beetles including Monochamus alternatus and Anoplophora glabripennis. Electroantennography (EAG) and a dynamic two-choice olfactometer were respectively used to measure the antennal and behavioral responses of both sexes to selected volatile compounds. Female and male D. helophoroides exhibited similar EAG and behavioral responses. Significant dose-dependent EAG responses in both sexes were elicited by nonanal, octanal, cis-3-hexenol, 3-carene, (R)-(+)-α-pinene, (S)-(-)-α-pinene, (R)-(+)-limonene and (S)-(-)-limonene. Female and male beetles were repelled at high concentration by cis-3-hexenol and (S)-(-)-limonene, respectively. Both sexes of D. helophoroides were significantly attracted to nonanal, cis-3-hexenol, 3-carene and (R)-(+)-limonene even at low concentrations. These compounds might be used either individually or in mixtures for developing biological control methods to attract this predatory beetle into forest stands threatened by cerambycid beetles.

Antennal sensilla and ovipositor morphology of the European birch sawfly Arge pullata Zadd (Hymenoptera: Tenthredinidae, Argidae).

Arge pullata Zadd is an important phytophagous pest that damages red birch Betula albo-sinensis in Hubei Province, South China. Massive ecological and economic losses have been caused by this species, which threatens the ecological security of the Shennongjia Nature Reserve. To investigate the mechanoreception, chemoreception, and oviposition processes of A. pullata, scanning electron microscopy and optical confocal microscopy were used to reveal the typology, morphology, and distribution of ovipositor and antennal sensilla. The results show that A. pullata has clavate antennae and eight types of sensilla in total, including sensilla chaetica, sensilla trichodea (types 1-3), sensilla basiconica, sensilla coeloconica (types 1 and 2), and Böhm's bristles. Sensilla trichodea type 1 distributed only on male antennae; the densities of sensilla trichodea type 2 and sensilla basiconica differed between the sexes. The binding pattern of ovipositor valvulae was discovered, and one type of sensilla chaetica, two types of sensory pits, and tooth-like cones as well as two types of microtrichia were found in the ovipositor. Based on morphological evidence and research on Hymenoptera, putative functions are suggested to increase our understanding of the mechanisms by which this species finds hosts and mates, and how oviposition takes place.

Antenna morphology and sensilla ultrastructure of Tetrigus lewisi Candèze (Coleoptera: Elateridae).

We used scanning and transmission electron microscopy to study the typology, morphology, distributions, and ultrastructures of the antennal sensilla of Tetrigus lewisi Candèze, a predatory click beetle that feeds on longhorned beetles, such as, Monochamus alternatus (Coleoptera: Cerambycidae). We observed eight types of sensilla on the antennae, including sensilla chaetica (with three subtypes: ch.1, ch.2, ch.3), sensilla basiconica (subtypes: ba.1, ba.2, ba.3), sensilla trichodea (subtypes: tr.1, tr.2), as well as sensilla auricillica, sensilla coeloconica, sensilla campaniformia, sensilla styloconica and Böhm's bristles. Significant sexual dimorphism was found in the antenna morphology, as well as in the density of type 2 sensilla trichodea and type 1 sensilla basiconica. We observed thick cuticular walls on sensilla chaetica, sensilla trichodea and sensilla campaniformia; clear pore structures on sensilla trichodea, sensilla basiconica and sensilla auricillica; and double walls with spoke-channels on sensilla coeloconica. The chemoreception, mechanoreception and thermo-/hygro-reception functions were deduced from fine structures on the cuticular walls and the dendrites of the different sensilla types. We suggest that all these sensilla have important roles in the host location, mating and predatory behavior of T. lewisi.

Genetic characterization of the gypsy moth from China (Lepidoptera, Lymantriidae) using inter simple sequence repeats markers.

This study provides the first genetic characterization of the gypsy moth from China (Lymantriadispar), one of the most recognized pests of forests and ornamental trees in the world. We assessed genetic diversity and structure in eight geographic populations of gypsy moths from China using five polymorphic Inter simple sequence repeat markers, which produced reproducible banding patterns. We observed 102 polymorphic loci across the 176 individuals sampled. Overall genetic diversity (Nei's, H) was 0.2357, while the mean genetic diversity within geographic populations was 0.1845 ± 0.0150. The observed genetic distance among the eight populations ranged from 0.0432 to 0.1034. Clustering analysis (using an unweighted pair-group method with arithmetic mean and multidimensional scaling), revealed strong concordance between the strength of genetic relationships among populations and their geographic proximity. Analysis of molecular variance demonstrated that 25.43% of the total variability (F ST = 0.2543, P < 0.001) was attributable to variation among geographic populations. The results of our analyses investigating the degree of polymorphism, genetic diversity (Nei's and Shannon) and genetic structure, suggest that individuals from Hebei may be better able to adapt to different environments and to disperse to new habitats. This study provides crucial genetic information needed to assess the distribution and population dynamics of this important pest species of global concern.

Scanning electron microscopy analysis of the cephalic sensilla of Chrysolina aeruginosa Fald. (Coleoptera, Chrysomelidae).

Chrysolina aeruginosa Fald. (Coleoptera, Chrysomelidae) is an important pest of Artemisia ordosica Krasch. In recent years, this phytophagous beetle has spread rapidly throughout northwest China, which has led to mass mortalities of the A. ordosica. This pest has caused great damage to the local ecology. To address this problem, this study compared the sensilla types and their densities on the antennae, maxillary palps, and labial palps of C. aeruginosa. Six different types of sensilla were observed on the antennae using scanning electron microscopy, i.e., sensilla chaetica, sensilla trichodea, sensilla basiconica, sensilla coeloconica, sensilla styloconica, and Böhm bristles. Sensilla chaetica were the main sensilla on the antennae. There was a significant difference in the distribution and density of sensilla trichodea between males and females. Sensilla basiconica were distributed from the fifth to the ninth flagellomeres. Sensilla coeloconica and sensilla styloconica were usually found from the fifth to the eighth flagellomeres. Böhm bristles were found only on the terminal region of the scape and pedicel. Sensilla chaetica and sensilla twig basiconica were observed on the maxillary and labial palps. Sensilla chaetica were distributed all over the maxillary and labial palps. Sensilla twig basiconica were located in the distal areas of these two types of palps. In this study, we also discussed the responses of C. aeruginosa to the volatile semiochemicals produced by their host plants and the behaviours exhibited during host and habitat selection.

Genetic structure in the seabuckthorn carpenter moth (Holcocerus hippophaecolus) in China: the role of outbreak events, geographical and host factors.

Understanding factors responsible for structuring genetic diversity is of fundamental importance in evolutionary biology. The seabuckthorn carpenter moth (Holcocerus hippophaecolus Hua) is a native species throughout the north of China and is considered the main threat to seabuckthorn, Hippophae rhamnoides L. We assessed the influence of outbreaks, environmental factors and host species in shaping the genetic variation and structure of H. hippophaecolus by using Amplified Fragment Length Polymorphism (AFLP) markers. We rejected the hypothesis that outbreak-associated genetic divergence exist, as evidenced by genetic clusters containing a combination of populations from historical outbreak areas, as well as non-outbreak areas. Although a small number of markers (4 of 933 loci) were identified as candidates under selection in response to population densities. H. hippophaecolus also did not follow an isolation-by-distance pattern. We rejected the hypothesis that outbreak and drought events were driving the genetic structure of H. hippophaecolus. Rather, the genetic structure appears to be influenced by various confounding bio-geographical factors. There were detectable genetic differences between H. hippophaecolus occupying different host trees from within the same geographic location. Host-associated genetic divergence should be confirmed by further investigation.

Scanning electron microscopy of antennal sensible of Anoplistes halodendri halodendri and Anoplistes halodendri ephippium (Coleoptera: Cerambycidae).

Anoplistes halodendri halodendri (Pallas, 1776) and Anoplistes halodendri ephippium (Stevens and Dalman, 1817) are two subspecies of the longicorn beetle A. halodendri (Coleoptera, Cerambycidae). In the recent years, these subspecies have been spreading rapidly in Hippophae rhamnoides and Hedysarum scoparium shrubberies in the Chinese provinces of Shanxi and Kingie, causing mass mortality of these shrubberies species and consequently leading to great damage to local ecological environment construction as well as high economic, ecological, and societal losses. To control their hazards effectively, here, we study and compare the types, densities, and distribution of antennal sensilla of A. h. halodendri and A. h. ephippium using scanning electron microscopy. Eight sensilla types were observed on the antennae of these two subspecies, including placoid sensilla (Ps), chaetica sensilla (ch) (types I-III), sensilla basiconica (b) (types I and II), sensilla gemmiformium (G), and auricillica sensilla (au). Ps predominated on the antennae of both A. h. halodendri and A. h. ephippium, followed by b and ch, and G and au. There were differences between the subspecies in the distribution and density of the different sensilla types, with ch I being found exclusively on the antennae of A. h. ephippium and b I and au on the antennae of A. h. halodendri only. With the exception of Ps, the densities of ch II, ch III, b II, and G on the antennae of A. h. halodendri were much higher than on the antennae of A. h. ephippium. These results provide sufficient evidence to clarify the receptive mechanisms used by these two subspecies of longicorn beetles and their responses to volatile semiochemicals released by their host plants as well as discuss their differences with respect to host and habitat selection.

Phylogenetic analysis and molecular evolution patterns in the MIR482-MIR1448 polycistron of Populus L.

The microRNAs (miRNAs) miR482 and miR1448 are disease resistance-related miRNAs; the former is ubiquitously distributed in seed plants whereas the latter has only been reported in Populus trichocarpa. The precursor and mature sequences of poplar miR1448 are highly homologous to those of poplar miR482, and these two miRNAs are located in one transcript as a polycistron. Therefore, we hypothesized that the MIR1448 gene may have evolved from the MIR482 gene in poplar. However, the molecular evolution patterns of this process remain unclear. In this study, utilizing cloning and Blast analysis in NCBI ESTs and whole-genome shotgun contigs (WGS) dataset, we determined that the MIR482-MIR1448 polycistron is a family-specific clustered miRNA in Salicaceae. Moreover, phylogenetic analysis illustrated that MIR1448 is the product of a tandem duplication event from MIR482. Nucleotide substitution analysis revealed that both MIR482 and MIR1448 have more rapid evolution ratios than ribosomal DNA (rDNA) genes, and that compensatory mutations that occurred in the stem region of the secondary structure were the main mechanisms that drove the evolution of these MIRNA genes. Furthermore, by comparing the substitution patterns in the miRNA-target complexes of miR482 and miR1448, we inferred that co-evolution between miRNAs and their targets was the major force that drove the "duplicated MIR482" evolve to MIR1448. We propose a novel miRNA-target pairing pattern called the "frameshift targeted mechanism" to explain the gain of target genes by miR1448. The results also imply that the major role of miR482 was in resistance to disease or other stresses via NBS-LRR proteins, whereas the biological functions of miR1448 are more diverse.

Olfactory and visual responses of the longlegged chafer Hoplia spectabilis Medvedev (Coleoptera: Scarabaeidae) in Qinghai Province, China.

BACKGROUND: Monitoring traps and control methods are needed for the long-legged chafer, Hoplia spectabilis Medvedev, which has recently reached outbreak numbers in pastureland of Qinghai Province, China. RESULTS: Field trapping experiments, using cross-pane funnel (barrier) traps, showed that H. spectabilis adults were not significantly attracted to branches of the host plant Dasiphora fructicosa (L.) Rydb. However, beetles were slightly attracted to similar host plant branches infested by conspecific beetles, possibly owing to weakly attractive volatiles, primarily (Z)-3-hexenyl acetate, released from beetle-damaged host leaves. This compound was weakly attractive when released from traps. However, H. spectabilis beetles showed strong visual responses to yellow- or white-painted trap panes, with weaker responses to blue, red or green panes, and least response to black panes. Black traps at 0.2-1.5 m above ground intercepted significantly more beetles than traps at 2.5 m. The mean flight height based on trap catches was 0.88 m (SD = 0.76), yielding an effective flight layer of 1.9 m. Flight response of beetles to colored barrier traps occurred between 10:00 and 18:00, and peaked between 12:00-14:00, when daily temperatures reached their maximum. CONCLUSION: Unbaited yellow or white cross-pane funnel traps are recommended for both monitoring and mass-trapping programs against this economically and ecologically important scarab beetle.