Assessing Genetic Variation in Resistance to Pinewood Nematode (Bursaphelenchus xylophilus) in Pinus radiata D. Don Half-Sib Families

Abstract

Full understanding and control of pine wilt disease (PWD) is a work in progress and breeding for disease resistance constitutes an essential management strategy for reducing its impact, as evidenced by advanced breeding programs in countries such as Japan. Since Pinus radiata is one of the most commercially relevant species in northern Spain, we designed a study to assess genetic variation in susceptibility to this pathogen using 44 P. radiata half-sib families from the Galician breeding program. Three Bursaphelenchus xylophilus (pinewood nematode, PWN) inoculation experiments were performed to evaluate disease-related variables, estimate genetic parameters, and study sources of genotype by environment interaction (G × E). We also looked at differences in the constitutive chemical compounds of susceptible and non-susceptible individuals. The results showed great variation in PWN susceptibility, with survival rates for P. radiata families ranging from 0% to 90%. In addition, heritability estimates (hi2 = 0.43, hf2 = 0.72) and genetic gain (>26% selecting 50% of the families) were both moderately high for survival. Significant differences in several constitutive chemical compounds were found between susceptible and non-susceptible seedlings in the two susceptibility groups considered. These results confirm the potential of breeding to obtain P. radiata genotypes that are resistant to pine wilt disease and open possibilities for mitigating its future impact on P. radiata stands.

Predicting the global potential distribution of Bursaphelenchus xylophilus using an ecological niche model: expansion trend and the main driving factors

“…We obtained occurrence point data for B. xylophilus from multiple sources, including the Centre for Agriculture and Bioscience International (CABI), the Global Biodiversity Information Facility (GBIF) (the last time to browse CABI was November 13, 2022, and to browse GBIF was November 8, 2022), Announcement No. 6 of 2022 issued by the State Forestry and Grassland Administration of China, and publicly available studies [ 30 , 39 – 41 ]. For locations mentioned in publicly available studies without latitude and longitude data, we used Google Earth (version 7.1) to obtain GPS coordinates.…”

Lessons from insect and disease impacts on radiata pine (Pinus radiataD. Don) plantations in New Zealand over the last hundred years

“…2018, Brockerhoff 2009, Brockerhoff et al 2023). Finally, although Brockerhoff (2009) suggested that radiata pine appeared to be resistant to the nematode B. xylophilus Steiner & Buhrer, that is spread by bark beetles, it has been found, after inoculation, to cause pine wilt disease in radiata pine in Spain (Menéndez-Gutiérrez et al . 2021).…”

“…Other secondary bark beetles known to attack weakened radiata pine outside New Zealand, and which might become vectors of PPC if this fungus appeared in New Zealand, are Orthotomicus erosus Wollaston, Pityophthorus pubescens Marsh., Dendroctonus valens Leconte and Tomicus pineperda L. (Bezos et al 2018, Brockerhoff 2009, Brockerhoff et al 2023. Finally, although Brockerhoff (2009) suggested that radiata pine appeared to be resistant to the nematode B. xylophilus Steiner & Buhrer, that is spread by bark beetles, it has been found, after inoculation, to cause pine wilt disease in radiata pine in Spain (Menéndez-Gutiérrez et al 2021). These authors found that it should be possible to breed trees resistant to these nematodes.…”

Selenium nanoparticles are effective in penetrating pine and causing high oxidative damage to Bursaphelenchus xylophilus in pine wilt disease control

“…First, PWNs were suspended in water at a concentration of 1000 PWNs/mL (as described above), and the inoculated hosts were 3-4-year-old Pinus koraiensis (purchased from Liaoning, China, with an average height of 40 cm and an average thickness of 1.5 cm and cultured in a greenhouse for 30 days before the experiment). The inoculation method was as follows 26,27 : the part with fewer needles of each plant was selected, and longitudinal incisions were made with a sterile blade. A piece of sterile absorbent cotton was inserted, and a pipette gun was used to transfer 1 mL of nematode suspension (1000 PWNs) into the absorbent cotton.…”