Studies On Phenolics Metabolism In Sweet Potato Infected By Fusarium Oxysporum Schlecht.f.sp.

Fusarium Oxysporum Schlecht.f.sp.batatas(wollenw.)Snyd.and Hans is the most important disease in Fujian, which affect the yield and quality on sweet potato. The work inoculated on resistant and sensitive variety, studied the metabolic rule of phenolics, which include total phenolics, flavonoid, lignin, chlorogenic acid, ferulic acid in plants, and the activity of correlative enzyme (PAL, POD), discussed the relationship between phenolics and resistance in sweet potato. The results as follow.1. PAL is the key enzyme of phenylpropanoid metabolize. The increase of PAL activity after inoculation is favorable for accelerated phenylpropanoid metabolize, which is a defence response to pathogen inbreak. The resistance would increased with increasing of level and rate of PAL activity.2. There were not difference in phenolics among different variety, total phenolics,flavonoid accumulated evidently in every variety. Resistant ability was correlation with accumulation rate and maintenance time of high concentration.3. There were significant difference in lignin and chlorogenic acid synthesization between resistant and sensitive variety. The resistant variety was faster than the sensitive varietyin synthesize quantity and time, which is good at resistant ability.4. SA is an important signal matter that can activate resistant response. SA affected on active oxygen metabolism, PAL activity and lignin synthesization.5. There were difference in some type of phenolics accumulation correlation with PAL activity between resistant and sensitive variety after pathogen be inocutated.