Effects of Temperature Factors on Resistance against Pine Wood Nematodes in Pinus thunbergii, Based on Multiple Location Sites Nematode Inoculation Tests

Abstract

Pine wilt disease (PWD) caused by the pinewood nematode (PWN) (Bursaphelenchus xylophilus (Steiner and Buhrer) Nickle) is a worldwide issue. Infection is considered to be promoted mainly by the increased air temperature, but it is important to investigate whether the effect of high temperature similarly influences the different ranks of resistant clone. In the present study, we conducted PWN inoculation tests using six common open-pollinated families of resistant Pinus thunbergii Parl. The tests were conducted at nurseries of five test sites across Japanese archipelago between 2015 and 2017. Our analysis focused specifically on temperature. Firstly, we examined the effects of test sites, inoculation year, and their interaction on unaffected seedling rate and found that the unaffected seedling rate of all tested pine families decreased as the cumulative temperature increased. We found that the unaffected seedling rate decreased as the cumulative temperature increased for all tested pine families. In general, higher cumulative temperatures were required for having an effect on the unaffected seedling rates of higher PWN-resistant families. Typically, early cumulative temperatures, i.e., 19 days after inoculation, had the greatest effect on the unaffected seedling rates of PWN-resistant pines. However, the relationship between cumulative temperature and predicted unaffected seedling rate follow similar rate for all families. Thus, the order of resistance level is maintained in terms of the cumulative temperature required for having an effect.

Effects of vegetation and topography on biomass patterns post-pinewood nematode disturbance in forest landscapes of southern Jiangxi Province, China

“…In this study, the estimation of biomass loss from the P.massoniana disease caused by pine wood nematodes and the correlation analysis of biomass loss with environmental factors on the plot scale provided a reference for estimating large-scale pest-related biomass losses and spatiotemporal changes in pest-related biomass losses. However, climatic conditions also lead to the aggravation and spread of pine wood nematodes and biomass losses (Enda and Mamiya 1972;Mcgawley E C et al 1985;Iki T et al 2020). This paper did not analyze the correlations between meteorological conditions or climatic factors and the degree of pine biomass loss; therefore, the results obtained in this paper had certain limitations.…”

Genetics and Improvement of Forest Trees

“…Carignato et al [7] report genetic variability in drought resistance among Eucalyptus clones and indicate the possibility of early selection in the nursery. Two papers evaluate selected P. thunbergii clones in terms of pine wood nematode resistance [8,9]. Iki et al [8] report that the cumulative temperature after nematode infection does not affect the resistance ranking of progeny seedlings of nematode-resistant pine wood clones.…”

“…Two papers evaluate selected P. thunbergii clones in terms of pine wood nematode resistance [8,9]. Iki et al [8] report that the cumulative temperature after nematode infection does not affect the resistance ranking of progeny seedlings of nematode-resistant pine wood clones. Matsunaga et al [9] examine the stability of traits in progeny seedlings moved to a different area from that in which they were selected.…”

Genetics and Improvement of Forest Trees

“…the possibility of early selection in the nursery. Two papers evaluate selected P. thunbergii clones in of pine wood nematode resistance [8,9]. Iki et al [8] report that the cumulative temperature after nematode infection does not the resistance ranking of progeny seedlings of nematode-resistant pine wood clones.…”

“…Two papers evaluate selected P. thunbergii clones in of pine wood nematode resistance [8,9]. Iki et al [8] report that the cumulative temperature after nematode infection does not the resistance ranking of progeny seedlings of nematode-resistant pine wood clones. Matsunaga et al [9] examine the stability of traits in progeny seedlings moved to a different area from that in which they were selected.…”