Relationship between Defense Enzyme and Masson Pine with Different Provenance Resistance to Pine Wood Nematode Disease

Colorimetry and polyacrylamide gel electrophoresis(PAGE) was used to comparatively study the dynamic change of activity of peroxidase(POD) and polyphemol oxidase(PPO) and their isoenzymes in masson pine(Pinus massoniana) resistant provenance Hengyang No.1 and sensitive provenance Guangxi No.1 after inoculation of pine wood nematode(Bursaphelenchus xylophilus).The results showed that activity of POD and PPO had two and one peak respectively in the resistant provenance;and the peak value of POD and PPO in resistant provenance was significantly higher than that of sensitive provenance.Isoenzyme electrophoresis revealed that though no new isozyme band of POD and PPO was detected in the resistant and sensitive provenance,the bands of enhanced POD isozyme of the resistant provenance were more than that of the sensitive provenance;meanwhile,some of PPO isozyme bands responded quickly to the invasion of pine wood nematode.These results suggested that POD and PPO played important roles in masson pine's resistance against pine wood nematode.