植物防御酶与桉树对焦枯病抗性的关系

为筛选鉴定桉树对焦枯病(CylindrocladiumqulnqueSeptatumMorgan)抗性的生化指标,对福建省11个桉树主栽种系接种焦枯病菌前后关键防御酶系中的过氧化物酶(POD)和超氧岐化酶(SOD)活性及其同工酶变化进行了研究.结果表明:无论是桉树健叶还是接种后的病叶,体内POD、SOD活性均表现为抗病种系>中抗种系>中感种系>感病种系,呈规律性变化;接种前后POD同工酶谱带数与桉树对焦枯病的抗性间不呈规律性变化,而SOD谱带数与抗病性成正比.从抗病育种角度出发可将接种前后桉树POD、SOD活性和接种后SOD同工酶谱带作为桉树对焦枯病抗性早期鉴定的生化指标.

Relationship between eucalyptus resistance to eucalyptus dieback and defense enzyme system

In order to determine the biochemical index, which indicates resistance of eucalyptus to eucalyptus dieback (Cylindrodadium quinqueseptatum Morgan), 11 eucalyptus cultivars were selected from Fujian Province and the activities of two major defense-enzymes, peroxidase (POD) and superoxide dismutase (SOD), analyzed. The results show that POD and SOD activities of healthy or infected leaves of the 11 cultivars change in a regular manner in the following order: resistant cultivar > moderate resistant cultivar > moderate susceptible cultivar > susceptible cultivar. POD isozyme band shows no regularity with resistance to eucalyptus dieback before or after inoculation, while SOD isozyme band has a relatively positive relation to the resistance to eucalyptus dieback. In relation to breeding, POD and SOD activity before and after inoculation and SOD isozyme bands after inoculation can be used as early biochemical indexes for resistance of eucalyptus to eucalyptus dieback.