Revealing the Complex Relationship Among Hyperspectral Reflectance, Photosynthetic Pigments, and Growth in Norway Spruce Ecotypes.

Norway spruce has a wide natural distribution range, harboring substantial physiological and genetic variation. There are three altitudinal ecotypes described in this species. Each ecotype has been shaped by natural selection and retains morphological and physiological characteristics. Foliar spectral reflectance is readily used in evaluating the physiological status of crops and forest ecosystems. However, underlying genetics of foliar spectral reflectance and pigment content in forest trees has rarely been investigated. We assessed the reflectance in a clonal bank comprising three ecotypes in two dates covering different vegetation season conditions. Significant seasonal differences in spectral reflectance among Norway spruce ecotypes were manifested in a wide-ranging reflectance spectrum. We estimated significant heritable variation and uncovered phenotypic and genetic correlations among growth and physiological traits through bivariate linear models utilizing spatial corrections. We confirmed the relative importance of the red edge within the context of the study site's ecotypic variation. When interpreting these findings, growth traits such as height, diameter, crown length, and crown height allowed us to estimate variable correlations across the reflectance spectrum, peaking in most cases in wavelengths connected to water content in plant tissues. Finally, significant differences among ecotypes in reflectance and other correlated traits were detected.

Trehalose determination in Norway spruce (Picea abies) roots. Analytics matters.

We present concise results of method validation for trehalose quantitation by LC-MS/MS in spruce ectomycorrhizal roots in order to describe spruce health status, mainly in connection to contamination by a pathogenic fungus, Gemmamyces piceae. The procedure is based on Rogatsky et al. (2005) developed for human plasma. We found out that the best extraction yield was achieved with 80% methanol/water (v/v) solution and optimal extraction temperature was set between 50-60°C. In contrast to previous papers, we minimized the activity of trehalase enzyme by putting root samples into liquid N2 immediately after root excavation, followed by freeze-drying in order to stop trehalase activity. Higher content of trehalose was recorded in healthy trees, confirming the idea that ectomycorrhiza plays a significant role in plant-pathogen interactions.