Spatiotemporal analysis of pine wilt disease: Relationship between pinewood nematode distribution and defence response in Pinus thunbergii seedlings

2019 ◽  
Vol 49 (4) ◽  
pp. e12518 ◽  
Author(s):  
Rimi Yamaguchi ◽  
Koji Matsunaga ◽  
Tomonori Hirao ◽  
Miho Tamura ◽  
Atsushi Watanabe
Keyword(s):  
Pine Wilt Disease ◽  
Spatiotemporal Analysis ◽  
Wilt Disease ◽  
Pinus Thunbergii ◽  
Defence Response ◽  
Pinewood Nematode ◽  
Pine Wilt

scholarly journals Spatiotemporal Pattern of Pine Wilt Disease in the Yangtze River Basin

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 731
Author(s):  
Zhuoqing Hao ◽  
Jixia Huang ◽  
Yantao Zhou ◽  
Guofei Fang
Keyword(s):  
River Basin ◽  
Yangtze River ◽  
Yangtze River Basin ◽  
Pine Wilt Disease ◽  
Wilt Disease ◽  
Spatiotemporal Pattern ◽  
Pinewood Nematode ◽  
The Yangtze River ◽  
Pine Wilt ◽  
The Yangtze River Basin

The Yangtze River Basin is among the river basins with the strongest strategic support and developmental power in China. As an invasive species, the pinewood nematode (PWN) Bursaphelenchus xylophilus has introduced a serious obstacle to the high-quality development of the economic and ecological synchronization of the Yangtze River Basin. This study analyses the occurrence and spread of pine wilt disease (PWD) with the aim of effectively managing and controlling the spread of PWD in the Yangtze River Basin. In this study, statistical data of PWD-affected areas in the Yangtze River Basin are used to analyse the occurrence and spread of PWD in the study area using spatiotemporal visualization analysis and spatiotemporal scanning statistics technology. From 2000 to 2018, PWD in the study area showed an “increasing-decreasing-increasing” trend, and PWD increased explosively in 2018. The spatial spread of PWD showed a “jumping propagation-multi-point outbreak-point to surface spread” pattern, moving west along the river. Important clusters were concentrated in the Jiangsu-Zhejiang area from 2000 to 2015, forming a cluster including Jiangsu and Zhejiang. Then, from 2015–2018, important clusters were concentrated in Chongqing. According to the spatiotemporal scanning results, PWD showed high aggregation in the four regions of Zhejiang, Chongqing, Hubei, and Jiangxi from 2000 to 2018. In the future, management systems for the prevention and treatment of PWD, including ecological restoration programs, will require more attention.

scholarly journals Characterization of bacterial communities associated with the pinewood nematode insect vector Monochamus alternatus Hope and the host tree Pinus massoniana

2020 ◽  
Author(s):  
Yajie Guo ◽  
Qiannan Lin ◽  
lvyi Chen ◽  
Carballar-Lejarazú Rebeca ◽  
Aishan Zhang ◽  
...  
Keyword(s):  
Pine Wilt Disease ◽  
Wilt Disease ◽  
Insect Vector ◽  
Insect Vectors ◽  
Pinewood Nematode ◽  
Monochamus Alternatus ◽  
Form Complex ◽  
Pine Wilt ◽  
Bacterial Microbiota ◽  
Habitat Niche

Abstract Background: Monochamus alternatus Hope is one of the insect vectors of pinewood nematode (Bursaphelenchus xylophilus), which causes the destructive pine wilt disease. The microorganisms within the ecosystem, comprising plants, their environment, and insect vectors, form complex networks. This study presents a systematic analysis of the bacterial microbiota in the M. alternatus midgut and its habitat niche.Methods: Total DNA was extracted from 20 types of samples (with three replicates each) from M. alternatus and various tissues of healthy and infected P. massoniana (pines). 16S rDNA amplicon sequencing was conducted to determine the composition and diversity of the bacterial microbiota in each sample. Moreover, the relative abundances of bacteria in the midgut of M. alternatus larvae were verified by counting the colony-forming units.Results: Pinewood nematode infection increased the microbial diversity in pines. Bradyrhizobium, Burkholderia, Dyella, Mycobacterium, and Mucilaginibacter were the dominant bacterial genera in the soil and infected pines. These results indicate that the bacterial community in infected pines may be associated with the soil microbiota. Interestingly, the abundance of the genus Gryllotalpicola was highest in the bark of infected pines. The genus Cellulomonas was not found in the midgut of M. alternatus, but it peaked in the phloem of infected pines, followed by the phloem of heathy pines. Moreover, the genus Serratia was not only present in the habitat niche, but it was also enriched in the M. alternatus midgut. The colony-forming unit assays showed that the relative abundance of Serratia sp. peaked in the midgut of instar II larvae (81%).Conclusions: Overall, the results indicate that the bacterial microbiota in the soil and in infected pines are correlated. The Gryllotalpicola sp. and Cellulomonas sp. are potential microbial markers of pine wilt disease. Additionally, Serratia sp. could be an ideal agent for expressing insecticidal protein in the insect midgut by genetic engineering, which represents a new use of microbes to control M. alternatus.

scholarly journals Systemic Acquired Resistance-Mediated Control of Pine Wilt Disease by Foliar Application With Methyl Salicylate

2022 ◽  
Vol 12 ◽  
Author(s):  
Hee Won Jeon ◽  
Ae Ran Park ◽  
Minjeong Sung ◽  
Namgyu Kim ◽  
Mohamed Mannaa ◽  
...  
Keyword(s):  
Methyl Salicylate ◽  
Systemic Acquired Resistance ◽  
Foliar Application ◽  
Acquired Resistance ◽  
Pine Wilt Disease ◽  
Wilt Disease ◽  
Pcr Analysis ◽  
Pinewood Nematode ◽  
Pine Wilt ◽  
Pine Seedlings

Pine wilt disease (PWD), caused by the pinewood nematode, is the most destructive disease in pine forest ecosystems worldwide. Extensive research has been done on PWD, but effective disease management is yet to be devised. Generally, plants can resist pathogen attack via a combination of constitutive and inducible defenses. Systemic acquired resistance (SAR) is an inducible defense that occurs by the localized infection of pathogens or treatment with elicitors. To manage PWD by SAR in pine trees, we tested previously known 12 SAR elicitors. Among them, methyl salicylate (MeSA) was found to induce resistance against PWD in Pinus densiflora seedlings. In addition, the foliar applications of the dispersible concentrate-type formulation of MeSA (MeSA 20 DC) and the emulsifiable concentrate-type formulation of MeSA (MeSA 20 EC) resulted in significantly reduced PWD in pine seedlings. In the field test using 10-year-old P. densiflora trees, MeSA 20 DC showed a 60% decrease in the development of PWD. Also, MeSA 20 EC gave the best results when applied at 0.1 mM concentration 2 and 1 weeks before pinewood nematode (PWN) inoculation in pine seedlings. qRT-PCR analysis confirmed that MeSA induced the expression of defense-related genes, indicating that MeSA can inhibit and delay the migration and reproduction of PWN in pine seedlings by modulating gene expression. These results suggest that foliar application of MeSA could reduce PWD incidence by inducing resistance and provide an economically feasible alternative to trunk-injection agents for PWD management.

Role of resin canals in the early stages of pine wilt disease caused by the pine wood nematode

1997 ◽  
Vol 75 (2) ◽  
pp. 346-351 ◽  
Author(s):  
Kyoko Ishida ◽  
Taizo Hogetsu
Keyword(s):  
Pine Wilt Disease ◽  
Wilt Disease ◽  
Pinus Thunbergii ◽  
Pine Wood Nematode ◽  
Pine Wood ◽  
Pine Wilt ◽  
Bark Peeling ◽  
Resin Canals ◽  
Cut Surface

The role of cortical resin canals in the early development of a pine wilt disease in Japanese black pine, Pinus thunbergii, was studied. A part of the bark of a 2 cm long segment from a current-year stem was removed by a tangential cut with a razor blade. Both cortex-exposed segments with cut cortical resin canals (designated as +RC segments) and those without cut resin canals (–RC segments) were obtained by chance. When a virulent nematode isolate (S6-1) was inoculated onto the cut surface, the surface of the +RC segments turned brown 4 d after inoculation, and in some segments this browning occurred more intensely around cortical resin canals. When segments were cut transversely at the middle, the transverse cut surface of the inoculated +RC segments was brown and fragile, but that of the inoculated –RC segments was pale green and stable, as was that of the non-inoculated controls. Correspondingly, tissue cells including epithelial cells of the cortical resin canal of the +RC segments were all dead, but those of the –RC segments and the controls were alive. When nematodes were inoculated onto the inner surface (cambium side) of a bark peeling at which cambial xylem cells were exposed, they did not kill the cambial cells. When inoculated on the transverse cut end of a bark peeling from which nematodes would enter resin canals, nematodes killed all cells in the peeling. The above results indicate that nematodes do not kill cortical cells immediately after inoculation but become harmful to pine cells after living in cortical resin canals. Key words: Bursaphelenchus xylophilus, pine wilt disease, pine wood nematode, Pinus thunbergii, resin canal.

scholarly journals Prevention of Pine Wilt of Scots Pine (Pinus sylvestris) with Systemic Abamectin Injections

2006 ◽  
Vol 32 (5) ◽  
pp. 195-201
Author(s):  
Randall James ◽  
Ned Tisserat ◽  
Tim Todd
Keyword(s):  
Pinus Sylvestris ◽  
Scots Pine ◽  
Pine Wilt Disease ◽  
Bursaphelenchus Xylophilus ◽  
Wilt Disease ◽  
Pinewood Nematode ◽  
Commercial Formulation ◽  
Breast Height ◽  
Pine Wilt ◽  
Trunk Injection

We examined the efficacy of the insecticide/nematicide abamectin to prevent pine wilt disease caused by the pinewood nematode (Bursaphelenchus xylophilus) in Scots pine (Pinus sylvestris). Pinewood nematode movement was inhibited (>80% death or paralysis) following a 48 hr exposure to abamectin concentrations as low as 0.1 μL a.i. per L (100 ppb). A commercial formulation of abamectin (Avid™) was injected into Scots pine using a pressurized systemic trunk injection tube (STIT) technique. Fifteen to 30 mL (0.45 to 0.90 fl oz) of Avid per STIT could be injected into the trees in less than 1 hr. Trees were successfully injected throughout February, March, and April at temperatures above 4.4°C (40°F). Survival after 1 year of 10 cm diameter (4 in) at breast height (dbh) Scots pines injected with Avid and subsequently inoculated with pinewood nematode was higher (75%) than in pines injected with water (42%). Similarly, survival after 3 years of large Scots pines (30 to 60 cm [12 to 24 in] dbh)] injected with Avid and exposed to a natural epidemic of pine wilt was higher (96%) than in noninjected pines (33%) or those injected with water (71%). These results indicate that preventive injections of Scots pine with Avid are effective in protecting against pine wilt disease.

Sign in / Sign up

Export Citation Format

Share Document