Whiteness of Paulow nia Wood and Physiological Indexes Correlated with Discoloration
An experiment was conducted to measure the wood whiteness of 25 individuals from Paulownia fortunei, P.tomento-sa, P.fargesii, P.kawakamii to select individuals with excellent wood color from Paulownia population, determine the key physiological indexes related to discoloration ( mass fraction of sugar and phenol, the activity of polyphenol oxidase (PPO) and peroxidase (POD)), and analyze correlation between the physiological indexes and wood whiteness.The differences of wood whiteness and the physiological indexes among individuals were statistically significant.The content of phenol negatively is correlated with wood whiteness (R=-0.518 62, P=0.009 4) and the sugar content is also negatively correlated with wood whiteness (R=-0.426 15, P=0.037 9).Both indexes can be used for indirect selection of Paulow-nia wood color, while the activity of PPO and POD can not be used for indirect selection.