氮钾水平与多酚氧化酶活性对柠檬流胶病抗性的影响

EFFECTS OF NITROGEN,POTASSIUM AND THE ACTIVITY OF PLOYPHENOL OXIDATE ON THE RESISTANCE OF LEMON GUMMOSIS

Ｎ，Ｋ水平与多酚氧化酶活性对柠檬抵御流胶病能力的影响研究表明，ＮＫ供应量与柠檬抵御流胶病病原菌侵染能力有密切关系，高Ｎ降低树体对流胶病的抵御能力，适当增加Ｋ浓度，能明显地提高其抗性。树体在中Ｎ和Ｋ偏高时，能较好地抵御流胶病的侵染，在一定范围内，Ｎ量增加，多酚氧化酶活性降低；Ｋ量增加，多酚氧化酶活性提高。提高多酚氧化酶酶活性，可以降低流胶病的感染。

In this paper,authors studied the influences of nitrogen and potassium levels inthe medium of sand culture for lemon seedlings((Citrus limon Burm,cv. Eureka)and theactivity of polyphenol oxidate(APO)on the resistance to lemon gummosis(Hendersonu-la toruloidea Nattrass).The results showed that the amounts of N and K applied wereclosely associated with the resistance to the infection strength of pathogenic gummosis. Ahigh level of N resulted in a diminution of the resistance,otherwise,the appropriately in-creased concentration of K could markedly strengthen this resistance. The trees cultured inthe medium with moderate level of N and higher level of K could fairly resist the disease,In some extent, when N is increased,the APO would be decreased;however,the APOwould be increased with the increasing concentration of K. So the augmentation of APOmight reduce the infection of lemon gummosis.