Research Of Early Diagnosis Based On Spectroscopy Of Pine Wood Nematode

Under the natural growth condition, healthy Pinus thunbergii was inoculated withthe pine wood nematode. With the deepening of disease severity, pine needles werecollected regularly to measure their spectral characteristics and electrical indicators.Through the analysis of pine needles’ reflectance curve of different experimentalinoculation types and different sampling times, it was indicated that at a wavelength of550nm in the green zone, the infection rate of pine wood nematode in pine needles wasgreater than0.15, however, healthy pine needles and pine needles which inoculated byMonochamus alternatus and pathogenic germ infection rates were less than0.15; in thenear infrared wavelength of750nm, the infection rate of pine needles infected by pinewood nematode was greater than0.6, while healthy pine needles and pine needles whichinoculated by Monochamus alternatus and pathogenic germ infection rates were lessthan0.6. The preliminary conclusion is that the reflection rate in the wavelength of550nm is0.15, and the reflection rate in the wavelength of750nm is0.6, these two setsof parameters can be regarded as the detection value of early nondestructive diagnosticmethods of pine wood nematode.