Diel Rhythmicity of Field Responses to Synthetic Pheromone Lures in the Pine Sawyer Monochamus saltuarius

The pine wood nematode (PWN), Bursaphelenchus xylophilus, causes lethal pine wilt disease (PWD) in Asia and Europe and has become a serious threat to global pine forest ecosystems. In Korea, Monochamus saltuarius transmits PWN not only to Pinus densiflora, but also to Pinus koraiensis, which is widely distributed across eastern Asia. The diel rhythmicity of M. saltuarius in response to its aggregation pheromone was studied with the aim of providing reliable data for the prevention of PWD and control of Monochamus spp. Using a spray dispenser controlled with an electronic timer, M. saltuarius pheromone and attractants (PA) were sprayed to determine the diel rhythm of the response to PA. The spraying period was divided into four time periods: 05:00–11:00 (time period A), 11:00–17:00 (time period B), 17:00–23:00 (time period C), and 23:00–05:00 (time period D). The largest number of M. saltuarius was caught in time period B, followed by A, C, and D. It could be concluded that the flight activity of M. saltuarius in response to PA was diurnal. The results of this study improve the understanding of the behavioral biology of M. saltuarius, allowing for the development of pest management strategies to prevent the spread of PWN and control its vector.

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Inhibition response of Pinus densiflora clones to Bursaphelenchus xylophilus systemic dispersal and their resistance to pine wilt disease

Nematology ◽

10.1163/138855410x535732 ◽

2011 ◽

Vol 13 (6) ◽

pp. 653-659 ◽

Cited By ~ 6

Author(s):

Katsumi Togashi ◽

Hiroko Maezono ◽

Koji Matsunaga ◽

Satoshi Tamaki

Keyword(s):

Pinus Densiflora ◽

Resistance Mechanism ◽

Pine Wilt Disease ◽

Bursaphelenchus Xylophilus ◽

Wilt Disease ◽

Pine Wilt ◽

Inhibition Response ◽

The Mean ◽

The Relationship ◽

Clone Group

AbstractTo determine the relationship between resistance to pine wilt disease and the inhibition of nematode systemic dispersal in Pinus densiflora, a suspension of 200 Bursaphelenchus xylophilus was placed on the upper cut end of 5-cm-long, living or boiled branch sections of 17 clones of pine that had different resistance levels. Significantly more nematodes passed through boiled sections than living sections during 24 h. Living branches of the resistant P. densiflora clone group significantly suppressed the dispersal of B. xylophilus compared with those of the susceptible group, suggesting that the inhibition of nematode systemic dispersal was involved in the resistance mechanism of selected disease-resistant pine clones. However, there was no significant correlation between the resistance class and the mean number of nematodes passing through live branch sections within the resistant clone group. The reason for the lack of correlation is discussed in relation with the resistance mechanism.

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Growth of Esteya vermicola in media amended with nitrogen sources yields conidia with increased predacity and resistance to environmental stress

Canadian Journal of Microbiology ◽

10.1139/w11-068 ◽

2011 ◽

Vol 57 (10) ◽

pp. 838-843 ◽

Cited By ~ 5

Author(s):

Zhen Wang ◽

Chun Yan Wang ◽

Li Juan Gu ◽

Yun Bo Wang ◽

Yong An Zhang ◽

...

Keyword(s):

Environmental Stress ◽

Ammonium Nitrate ◽

Significant Influence ◽

Pine Wilt Disease ◽

Nitrogen Sources ◽

Dry Mass ◽

Bursaphelenchus Xylophilus ◽

Pinewood Nematode ◽

Esteya Vermicola ◽

And Control

Esteya vermicola , an endoparasitic fungus of pinewood nematode, exhibits great potential as a biological agent against nematodes. In this study to enhance the sporulation, predacity, and environmental resistance of E. vermicola, various nitrogen sources, such as glycine, l-leucine, and ammonium nitrate, were tested. The supplement of glycine and l-leucine had a significant influence on the growth rate of the colony, enhancing colony dry mass by 5-fold more than did ammonium nitrate or the control. Of the nitrogen sources tested, ammonium nitrate and l-leucine promoted sporulation, yielding more than 6 × 106 CFU/g, while glycine enhanced the proportion of lunate spores. Meanwhile, the supplement of nitrogen sources had a significant influence on adhesive rate and mortality rate against Bursaphelenchus xylophilus . Moreover, the supplement of glycine enhanced the survival rate against heat stress by more than 3-fold that of l-leucine, ammonium nitrate, and control. The spores produced in media amended with glycine, l-leucine, and ammonium nitrate had slightly but not significantly higher UV resistance and drought resistance than spores produced without nitrogen sources. These results suggested that the addition of glycine resulted in the production of E. vermicola conidia with increased predacity and resistance to environmental stress that may be more suitable for control of pine wilt disease.

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New data on the distribution and abundance of Dendrolimus sibiricus (Tshetverikov, 1908) (Lepidoptera: Lasiocampidae) in the Komi Republic.

10.21203/rs.3.rs-900432/v1 ◽

2021 ◽

Author(s):

Alexander Lukin

Keyword(s):

Forest Ecosystems ◽

Coniferous Forest ◽

Komi Republic ◽

Middle Taiga ◽

Pheromone Traps ◽

Northern Forest ◽

The Past ◽

Synthetic Pheromone ◽

Preimaginal Stages ◽

And Control

Abstract The Siberian silkworm (Dendrolimus sibiricus Tschetv.) is a defoliator pest that poses a significant threat to coniferous forest stands. Over the past decades, several large outbreaks of this species have occurred in Siberia (Russia), which has led to changes in forest ecosystems and an increase of expenses involved in reforestation. Adults capture new territories in the process of migration, therefore, a set of measures is needed to register the number and prevent further dispersal of the moth. One of methods of trapping is glue traps with synthetic pheromone. 16 district forestries located in the middle taiga subzone, with a total area of 151 850 hectares, were surveyed as a part of the phytosanitary monitoring of the Siberian silkworm in the Komi Republic (Russia). Analysis of 773 pheromone traps showed 414 males of the target species that were identified by their genitals. The highest indicators of catchability were found in three district forestries. Taking into account the results obtained, it was proposed to continue the monitoring using the pheromone traps, to survey more northern forest districts and to carry out subsequent searches for preimaginal stages of the silkworm in the forest districts of Priluzsky district. The study will be useful for predicting the further spread of the silkworm and for developing optimal containment and control of the pest.

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Resistance of an indigenous biological system against expansion of the invasive nematode, Bursaphelenchus xylophilus, in cool areas of Japan

Nematology ◽

10.1163/156854108785787172 ◽

2008 ◽

Vol 10 (5) ◽

pp. 679-687 ◽

Cited By ~ 2

Author(s):

Shota Jikumaru ◽

Katsumi Togashi

Keyword(s):

Air Temperature ◽

Pinus Densiflora ◽

Pine Wilt Disease ◽

Bursaphelenchus Xylophilus ◽

Vector System ◽

Insect Vector ◽

Disease Development ◽

Biotic Factors ◽

Pine Tree ◽

Pine Trees

Abstract Bursaphelenchus xylophilus is the pathogen associated with pine wilt disease (PWD), an infectious disease of pine trees transmitted by cerambycid beetles of the genus Monochamus. Bursaphelenchus xylophilus is an invasive species, whilst B. mucronatus is a native congener and non-pathogenic to pine trees in Japan. To provide experiment evidence of the biotic and/or abiotic resistance to PWD expansion in a cool area of Japan, we inoculated B. xylophilus into healthy pine trees in a Japanese red pine (Pinus densiflora) stand with the indigenous pine tree-B. mucronatus-insect vector system before invasion of B. xylophilus in 1993 and 1994. Extremely cool air temperature with high precipitation and extremely high air temperature with low precipitation were observed in the summers of the 2 years of inoculation, respectively. The cool summer induced a low incidence of PWD and delayed disease development, resulting in the replacement of B. xylophilus by B. mucronatus within diseased trees and the emergence of Monochamus saltuarius beetles carrying B. mucronatus from the trees 2 years after the inoculation. The hot summer induced disease development in trees in the year of inoculation, but such diseased trees did not become infection sources because of the lack of M. alternatus, whose oviposition was synchronised with the period of disease development in pine trees. This study indicated that biotic factors were important in the inhibitory mechanism in a pine forest against the spread of PWD in the stand. Relevant biotic factors were the lack of M. alternatus and the presence of M. saltuarius carrying B. mucronatus.

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Seasonal change in susceptibility of Pinus densiflora to Bursaphelenchus xylophilus infection, determined from the number of nematodes passing through branch sections

Nematology ◽

10.1163/156854109x446980 ◽

2009 ◽

Vol 11 (3) ◽

pp. 409-418 ◽

Cited By ~ 6

Author(s):

Koji Matsunaga ◽

Katsumi Togashi

Keyword(s):

Seasonal Change ◽

Developmental Stages ◽

Pinus Densiflora ◽

Pine Wilt Disease ◽

Bursaphelenchus Xylophilus ◽

Control Measures ◽

Effective Control ◽

Dispersal Ability ◽

Second Stage ◽

Individual Branch

AbstractPine wilt disease by Bursaphelenchus xylophilus has been causing devastating damage to Pinus densiflora and P. thunbergii forests in Japan. Reforestation using resistant trees is one of the most effective control measures. In this study we examined the seasonal change in the number of nematodes passing through 5 cm long P. densiflora branch sections during 24 h, to determine the season of greatest susceptibility when resistant candidates can be identified easily. We inoculated 200 nematodes of each of four B. xylophilus and one B. mucronatus isolate on the cut end of individual branch sections. The overall seasonal change in the number of nematodes passing was similar among the five isolates. Peaks occurred in August and between December and February for four isolates. A virulent isolate, T-4, exhibited remarkable fluctuations, with the highest peak in August, suggesting that a test in August with T-4 is most informative. Another study showed that the passage ability, which is a measure of the dispersal ability in branches, was low for eggs and second-stage propagative juveniles and high for other developmental stages. This indicates that the composition of developmental stages in the inoculum is important when comparing the numbers of passing nematodes obtained on different occasions and in different places.

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Nematicidal Activity of Benzyloxyalkanols against Pine Wood Nematode

Biomolecules ◽

10.3390/biom11030384 ◽

2021 ◽

Vol 11 (3) ◽

pp. 384

Author(s):

Junheon Kim ◽

Su Jin Lee ◽

Joon Oh Park ◽

Kyungjae Andrew Yoon

Keyword(s):

Forest Ecosystems ◽

Pine Wilt Disease ◽

Bursaphelenchus Xylophilus ◽

Nematicidal Activity ◽

Environmental Damage ◽

Pine Wood Nematode ◽

Glutathione S Transferase ◽

Pine Wood ◽

Chemical Treatments ◽

Continuous Use

Pine wilt disease (PWD) is caused by the pine wood nematode (PWN; Bursaphelenchus xylophilus) and causes severe environmental damage to global pine forest ecosystems. The current strategies used to control PWN are mainly chemical treatments. However, the continuous use of these reagents could result in the development of pesticide-resistant nematodes. Therefore, the present study was undertaken to find potential alternatives to the currently used PWN control agents abamectin and emamectin. Benzyloxyalkanols (BzOROH; R = C2–C9) were synthesized and the nematicidal activity of the synthetic compounds was investigated. Enzymatic inhibitory assays (acetylcholinesterase (AChE) and glutathione S-transferase (GST)) were performed with BzOC8OH and BzOC9OH to understand their mode of action. The benzyloxyalkanols showed higher nematicidal activity than did benzyl alcohol. Among the tested BzOROHs, BzC8OH and BzC9OH showed the strongest nematicidal activity. The LD50 values of BzC8OH and BzC9OH were 246.1 and 158.0 ppm, respectively. No enzyme inhibitory activity was observed for BzC8OH and BzC9OH. The results suggested that benzyloxyalcohols could be an alternative nematicidal agent.

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Is Bursaphelenchus mucronatus a weak pathogen to the Japanese red pine?

Nematology ◽

10.1163/156854106778613994 ◽

2006 ◽

Vol 8 (4) ◽

pp. 485-489 ◽

Cited By ~ 15

Author(s):

Kazuyoshi Futai ◽

Natsumi Kanzaki

Keyword(s):

Pinus Densiflora ◽

Pine Wilt Disease ◽

Bursaphelenchus Xylophilus ◽

Transmission Efficiency ◽

Monochamus Alternatus ◽

Disease Symptoms ◽

Host Trees ◽

Bursaphelenchus Mucronatus ◽

Pine Trees ◽

Mutualistic Relationship

AbstractThe pine wood nematode, Bursaphelenchus xylophilus, is the causal agent of pine wilt disease. It can invade healthy pine trees through the feeding wound of its vector beetle, Monochamus alternatus, and can enter a dead or dying tree through the vector's oviposition mark. By contrast, B. mucronatus, which is closely related to B. xylophilus but has been considered to have no pathogenicity to pine species, also invades living host trees through the same process as B. xylophilus, although the transmission efficiency is lower than that of B. xylophilus. In order to clarify the reason why Bursaphelenchus mucronatus invades a living host, we inoculated shaded and unshaded host seedlings of Pinus densiflora with B. mucronatus. Bursaphelenchus mucronatus displayed pathogenicity in the host seedlings but only with those that were shaded. In addition, B. mucronatus was recovered from the seedlings that had survived until the end of the experiment. Bursaphelenchus mucronatus seems to survive in the living healthy host tree without causing disease symptoms. These results suggest a mutualistic relationship between B. mucronatus and its vector beetle.

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The effect of endobacteria on the development and virulence of the pine wood nematode, Bursaphelenchus xylophilus

Nematology ◽

10.1163/15685411-00002892 ◽

2015 ◽

Vol 17 (5) ◽

pp. 581-589 ◽

Cited By ~ 5

Author(s):

Xiao-Jing Tian ◽

Xiao-Qin Wu ◽

Yang Xiang ◽

Xin Fang ◽

Jian-Ren Ye

Keyword(s):

Stenotrophomonas Maltophilia ◽

Pinus Densiflora ◽

Pine Wilt Disease ◽

Bursaphelenchus Xylophilus ◽

Wilt Disease ◽

Achromobacter Xylosoxidans ◽

Pine Wood Nematode ◽

Pine Wood ◽

Forest Disease ◽

High Virulence

Pine wilt disease (PWD) caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus, is a destructive forest disease. Recent studies showed that bacteria associated with PWN might play important roles in PWD. In this study, the effects of endobacteria isolated from PWN on the development and virulence of PWN were evaluated. The results revealed that endobacteria isolated from high virulence PWN could partially promote the development of the nematode, while endobacteria from PWN with low virulence could inhibit the development of nematode. Both bacteria-free and non-sterilised nematodes were able to infect microcuttings of Pinus densiflora. The endobacterial isolates, Stenotrophomonas maltophilia NSBx.14 and Achromobacter xylosoxidans ssp. xylosoxidans NSBx.22, enhanced the virulence of low virulence PWN but reduced the virulence of high virulence PWN. The results suggest the pathogenicity of PWN is not affected by loss of bacteria and endobacteria might play a role in the development and virulence of PWN.

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First Report of Pine Wilt Disease on Pinus koraiensis in Korea

Plant Disease ◽

10.1094/pdis-92-8-1251a ◽

2008 ◽

Vol 92 (8) ◽

pp. 1251-1251 ◽

Cited By ~ 12

Author(s):

H. Han ◽

Y.-J. Chung ◽

S.-C. Shin

Keyword(s):

Dna Sequences ◽

Pinus Densiflora ◽

Pine Wilt Disease ◽

Wilt Disease ◽

Internal Transcribed Spacers ◽

Pinus Koraiensis ◽

Korean Pine ◽

Accurate Identification ◽

First Report ◽

Pine Wilt

Pine wilt disease is one of the most important forest tree diseases, especially in the East Asian countries of Japan, China, and Korea. The causal agent, Bursaphelenchus xylophilus (3), is transmitted by the insect vectors, pine sawyer beetles (Monochamus spp.). The vectors mainly attack coniferous trees and the infected trees die within several weeks. In Korea, pine wilt disease was first reported in Busan City in 1988, and now, the damaged area covers 7,820 ha and more than 60 cities in Korea. The main host trees are Pinus densiflora and P. thunbergii, which are the most common pines distributed in Korea. In 2006, however, we found pine wilt disease in a forest of P. koraiensis located in Gwangju City in Gyeonggi Province. Symptoms were systemic and leaves turned brown or yellowish. Wood samples were collected from the affected trees, and nematodes were extracted by a modified Baermann's funnel method. After 24 h, nematodes were collected from wood chips, and morphology was observed with an inverted light microscope (Leica DE/DMI 3000B, Wetzlar, Germany). Morphology was characterized by a typical Aphelenchoid-type esophagus, head constriction, female vulva flap, female tail, and a male spicule shape similar to B. xylophilus. For more accurate identification, DNA was extracted from individual nematodes with a DNeasy Kit (Qiagen, Valencia, CA). The internal transcribed spacers (ITS) 1 and 2 and 5.8S regions were amplified by PCR (1). Sequenced nucleotide information was compared with the sequences of B. xylophilus already reported in GenBank (Accession Nos. AB294736, AB277208, AM 157747, AY 347913, and BXU92464). ITS DNA sequences of the nematode from Korean pine was >99% identical to B. xylophilus in GenBank. The B. xylophilus from Korean pine tree was also successfully cultured in Botrytis cinerea medium and pathogenicity was tested from June to October 2007. More than 95% mortality was observed with the inoculation of 20 replicate 15-year-old trees of P. koraiensis and P. densiflora with 15,000 nematodes per tree. Therefore, we confirmed that pine wilt disease occurred in P. koraiensis in Korea. P. koraiensis is an endemic species in Korea and distribution is limited to the northern Korean Peninsula and some locations in Russia. It has been shown that P. koraiensis is susceptible to the pine wood nematode by an inoculation test in Japan (2); however, to our knowledge, this is the first report of pine wilt disease on P. koraiensis under field conditions in Korea. References: (1) W. K. Burgermeister et al. Russ. J. Nematol. 13:29, 2005. (2) K. Futai and T. Furuno. Bull. Kyoto Univ. For. 51:3, 1979. (3) G. Steiner and E. M. Buhrer. J. Agr. Res. 48:946, 1934.

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Diagnosis of pine wilt disease using remote wireless sensing

PLoS ONE ◽

10.1371/journal.pone.0257900 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257900

Author(s):

Sang-Kyu Jung ◽

Seong Bean Park ◽

Bong Sup Shim

Keyword(s):

Pinus Densiflora ◽

Pine Wilt Disease ◽

Bursaphelenchus Xylophilus ◽

Wilt Disease ◽

Boundary Line ◽

Absolute Deviation ◽

Linear Discriminant ◽

Tree Disease ◽

Pine Wilt ◽

Stem Resistance

Pine wilt disease caused by Bursaphelenchus xylophilus is a major tree disease that threatens pine forests worldwide. To diagnose this disease, we developed battery-powered remote sensing devices capable of long-range (LoRa) communication and installed them in pine trees (Pinus densiflora) in Gyeongju and Ulsan, South Korea. Upon analyzing the collected tree sensing signals, which represented stem resistance, we found that the mean absolute deviation (MAD) of the sensing signals was useful for distinguishing between uninfected and infected trees. The MAD of infected trees was greater than that of uninfected trees from August of the year, and in the two-dimensional plane, consisting of the MAD value in July and that in October, the infected and uninfected trees were separated by the first-order boundary line generated using linear discriminant analysis. It was also observed that wood moisture content and precipitation affected MAD. This is the first study to diagnose pine wilt disease using remote sensors attached to trees.

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