黑斑病对甘薯叶酚类物质含量、PPO及PAL活性的影响

选用对甘薯黑斑病抗性不同的品种南京-92(高抗)和烟台-252(高感)的叶片为材料,研究黑斑病对甘薯叶总酚含量、绿原酸含量、类黄酮含量以及苯丙氨酸解氨酶(PAL)活性和酚氧化酶(PPO)活性的影响。结果表明:在未受黑斑病侵染时,南京-92叶片中类黄酮含量、绿原酸含量、PAL活性显著或极显著高于烟台-252,可以作为选育和鉴定抗黑斑病品种的生理指标,但总酚含量和PPO活性差异不显著。接种后2～8d内,南京-92叶片内总酚含量和PPO活性增加迅速,与烟台-252达到显著或极显著差异,总酚含量和PPO活性的上升速度快、保持时间长,有利于提高对黑斑病的抵抗能力。

Effects of Ceratocystis fimbriata on phenolics content,PPO and PAL activityin sweet potato

Two varieties of sweet potato including high resistance-Nanjing-92and high susceptible-Yantai-252to Ceratocystis fimbriata were used for detection the content of total phenol,chlorogenic acid,flavonoid and the activity of PPO and PAL in sweet potato leaves.The results showed that flavonoid content,chlorogenic acid content and PAL activity of Nanjing-92were higher than that of Yantai-252and even reached significant or extremely significant difference in normal condition,which could be regarded as physiological indices of identifying and selecting resistant variety.It was also found that total phenol content and PPO activity of two varieties were not significant different in normal condition,however,when infected by C.fimbriata,total phenol content and PPO activity of Nanjing-92increased sharply and significant or extremely significant higher than that of Yantai-252within 2th to 8th day.The total phenol content and PPO activity raised speedily and maintained long period which could increase the resistance ability to C.fimbriataof sweet potato.