Physiological response of Pinus spp. in the first hours after infection with Bursaphelenchus xylophilus (Nematoda: Aphelenchoididae).
The purpose of this study was to compare the response to infection with the pine wood nematode (PWN) Bursaphelenchus xylophilus between Pinus pinaster and Pinus pinea at an initial stage of the disease, three hours after inoculation. The PWN is the causal agent of pine wilt disease, in Portugal its main host is the maritime pine, P. pinaster, and its vector is Monochamus galloprovincialis. Currently there are no studies that describe the effects of nematode infection in plants at an early stage of the disease and with regards to the physiological and metabolic indicators of the disease response in the plants, there was a decrease of 10.9% of water content in P. pinaster (compared with trees inoculated with water) and 6.7% in P. pinea; in the study of total chlorophyll concentration, a decrease to about half of the control value was recorded for both species, but more pronounced in P. pinaster. An exploratory study was also made with gas chromatography, which showed that the volatile compounds produced were distinct between species, but not between control vs. nematode-inoculated plants.