Potential of the fumigant ethanedinitrile to kill the pinewood nematode ( Bursaphelenchus xylophilus ) and other forest pathogens

AbstractThe third-stage dispersal juvenile (DJ3) of pinewood nematode (PWN) is highly associated with low-temperature survival and spread of the nematode. Oil-Red-O staining showed that its lipid content was significantly higher compared with other PWN stages. Weighted gene coexpression network analysis identified that genes in the pink module were highly related to DJ3 induced in the laboratory (DJ3-lab). These genes were arranged according to their gene significance (GS) to DJ3-lab. Of the top 30 genes with the highest GS, seven were found to be highly homologous to the cysteine protease family cathepsin 1 (CATH1). The top 30 genes with the highest weight value to each of the seven genes in the pink module were selected, and finally 35 genes were obtained. Between these seven CATH1 homologous genes and their 35 highly related genes, 15 were related to fat metabolism or autophagy. These autophagy-related genes were also found to be highly correlated with other genes in the pink module, suggesting that autophagy might be involved in the mechanism of longevity in DJ3 and the formation of DJ3 by regulating genes related to fat metabolism.

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Chitosan increases Pinus pinaster tolerance to the pinewood nematode (Bursaphelenchus xylophilus) by promoting plant antioxidative metabolism

Scientific Reports ◽

10.1038/s41598-021-83445-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Marta Nunes da Silva ◽

Carla S. Santos ◽

Ana Cruz ◽

Adrián López-Villamor ◽

Marta W. Vasconcelos

Keyword(s):

Phenolic Compounds ◽

Pinus Pinaster ◽

Plant Defence ◽

Pine Wilt Disease ◽

Bursaphelenchus Xylophilus ◽

Nematode Population ◽

Post Inoculation ◽

Pinewood Nematode ◽

Plant Tolerance ◽

The Moment

AbstractThe pine wilt disease (PWD), for which no effective treatment is available at the moment, is a constant threat to Pinus spp. plantations worldwide, being responsible for significant economic and environmental losses every year. It has been demonstrated that elicitation with chitosan increases plant tolerance to the pinewood nematode (PWN) Bursaphelenchus xylophilus, the causal agent of the PWD, but the biochemical and genetic aspects underlying this response have not been explored. To understand the influence of chitosan in Pinus pinaster tolerance against PWN, a low-molecular-weight (327 kDa) chitosan was applied to mock- and PWN-inoculated plants. Nematode population, malondialdehyde (MDA), catalase, carotenoids, anthocyanins, phenolic compounds, lignin and gene expression related to oxidative stress (thioredoxin 1, TRX) and plant defence (defensin, DEF, and a-farnesene synthase, AFS), were analysed at 1, 7, 14, 21 and 28 days post-inoculation (dpi). At 28 dpi, PWN-infected plants elicited with chitosan showed a sixfold lower nematode population when compared to non-elicited plants. Higher levels of MDA, catalase, carotenoids, anthocyanins, phenolic compounds, and lignin were detected in chitosan-elicited plants following infection. The expression levels of DEF gene were higher in elicited plants, while TRX and AFS expression was lower, possibly due to the disease containment-effect of chitosan. Combined, we conclude that chitosan induces pine defences against PWD via modulation of metabolic and transcriptomic mechanisms related with plant antioxidant system.

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In Silico Screening of Agonist and Antagonist Natural Compounds from Reported Essential Oils against Bursaphelenchus xylophilus

Chemistry Proceedings ◽

10.3390/ecsoc-24-08386 ◽

2020 ◽

Vol 3 (1) ◽

pp. 31

Author(s):

Jorge M. S. Faria ◽

Ana Margarida Rodrigues ◽

Pedro Barbosa ◽

Manuel Mota

Keyword(s):

Essential Oils ◽

Pine Wilt Disease ◽

Natural Compounds ◽

Bursaphelenchus Xylophilus ◽

Pinewood Nematode ◽

Highly Active ◽

Bibliographic Data ◽

Agonist And Antagonist ◽

Containment Strategy ◽

Detailed Chemical

Chemical control has been the most effective and reliable containment strategy in integrated pest management of pine wilt disease (PWD), caused by the pinewood nematode (PWN), Bursaphelenchus xylophilus. Yet, large spectrum nematicides can be dangerous to human health and the environment. Essential oils (EOs) are safer sustainable alternatives, being composed of highly active natural compounds. A survey of bibliographic data on the detailed chemical composition and activity of the EOs used against the PWN allowed pinpointing monoterpenes as the main source of structures with agonist or antagonist properties. Transversal EO data treatment can identify potential highly active anti-PWN compounds.

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Satellite DNA as a target for TaqMan real-time PCR detection of the pinewood nematode, Bursaphelenchus xylophilus

Molecular Plant Pathology ◽

10.1111/j.1364-3703.2007.00434.x ◽

2007 ◽

Vol 8 (6) ◽

pp. 803-809 ◽

Cited By ~ 42

Author(s):

CECILE FRANÇOIS ◽

CHANTAL CASTAGNONE ◽

NEIL BOONHAM ◽

JENNY TOMLINSON ◽

REBECCA LAWSON ◽

...

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Satellite Dna ◽

Bursaphelenchus Xylophilus ◽

Pcr Detection ◽

Pinewood Nematode

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Molecular and biochemical characterization of an endo-β-1,3-glucanase from the pinewood nematode Bursaphelenchus xylophilus acquired by horizontal gene transfer from bacteria

Biochemical Journal ◽

10.1042/bj20042042 ◽

2005 ◽

Vol 389 (1) ◽

pp. 117-125 ◽

Cited By ~ 86

Author(s):

Taisei KIKUCHI ◽

Hajime SHIBUYA ◽

John T. JONES

Keyword(s):

Gene Transfer ◽

Horizontal Gene Transfer ◽

Biochemical Characterization ◽

Glycosyl Hydrolase ◽

Functional Characterization ◽

Nematode Species ◽

Bursaphelenchus Xylophilus ◽

Pinewood Nematode ◽

Sequence Comparisons

We report the cloning and functional characterization of an endo-β-1,3-glucanase from the pinewood nematode Bursaphelenchus xylophilus acquired by horizontal gene transfer from bacteria. This is the first gene of this type from any nematode species. We show that a similar cDNA is also present in another closely related species B. mucronatus, but that similar sequences are not present in any other nematode studied to date. The B. xylophilus gene is expressed solely in the oesophageal gland cells of the nematode and the protein is present in the nematode's secretions. The deduced amino acid sequence of the gene is very similar to glycosyl hydrolase family 16 proteins. The recombinant protein, expressed in Escherichia coli, preferentially hydrolysed the β-1,3-glucan laminarin, and had very low levels of activity on β-1,3-1,4-glucan, lichenan and barley β-glucan. Laminarin was degraded in an endoglucanase mode by the enzyme. The optimal temperature and pH for activity of the recombinant enzyme were 65 °C and pH 4.9. The protein is probably important in allowing the nematodes to feed on fungi. Sequence comparisons suggest that the gene encoding the endo-β-1,3-glucanase was acquired by horizontal gene transfer from bacteria. B. xylophilus therefore contains genes that have been acquired by this process from both bacteria and fungi. These findings support the idea that multiple independent horizontal gene transfer events have helped in shaping the evolution of several different life strategies in nematodes.

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Study of symptoms and gene expression in four Pinus species after pinewood nematode infection

Plant Genetic Resources ◽

10.1017/s1479262111000062 ◽

2011 ◽

Vol 9 (2) ◽

pp. 272-275 ◽

Cited By ~ 5

Author(s):

Albina R. Franco ◽

Carla Santos ◽

Mariana Roriz ◽

Rui Rodrigues ◽

Marta R. M. Lima ◽

...

Keyword(s):

Virulent Strain ◽

Pine Wilt Disease ◽

Bursaphelenchus Xylophilus ◽

Wilt Disease ◽

Pinewood Nematode ◽

Pine Trees ◽

Severe Infections ◽

Genomic Results ◽

Avirulent Isolate

Pine wilt disease, caused by the pinewood nematode Bursaphelenchus xylophilus (Steiner and Buhrer) Nickle, is originating severe infections in pine trees. The disease is detected when external symptoms appear (e.g. needle chlorosis), but trees could remain asymptomatic for long periods and serve as a long-term host. The primary goal of this study was to assess the effect of inoculation with an avirulent isolate of B. xylophilus (C14-5) on different Pinus spp. seedlings (P. sylvestris, P. nigra, P. pinea and P. pinaster). At the same time, seedlings were also inoculated with a virulent strain, HF, in order to compare the phenotypic and genomic results of the two types of inoculations. The effect of inoculation was determined in terms of expression of various Pinus genes potentially involved in the response to the disease.The results suggest that P. pinea and P. nigra are more resistant to infection by the nematode than P. sylvestris and P. pinaster. The phenotypic and genetic differences were more marked among P. pinea and P. pinaster.

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