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作 者 ：刘业霞1，付 玲1，艾希珍1*，张 宁1，王洪涛2，姬德刚2

期 刊 ：西北植物学报 2012年 5期 页码：963~968

关键词：嫁接；青枯病；微生物；土壤酶；辣椒；

Keywords:graft, bacterical wilt, microorganism, soil enzyme, pepper (Capsicum annuum L.),

摘 要 ：以‘卫士’辣椒为砧木，‘新丰2号’为接穂嫁接，通过人工接种青枯病菌研究嫁接和自根辣椒根系特征、根际土壤微生物及酶活性的变化，探讨嫁接辣椒的抗病机理。结果显示：接种青枯病菌前，嫁接辣椒的根系重量、总长度、总体积、表面积、根尖数和分叉数均显著高于自根苗，根系活力、根际土壤放线菌数量和比例，以及根际土壤酶（多酚氧化酶、过氧化物酶和脱氢酶）活性也明显高于自根苗。接种青枯病菌后，嫁接辣椒的根系受伤程度较自根苗轻，根系重量、总长度、总体积、表面积、根尖数和分叉数的降低幅度均显著小于自根苗，根系活力、根际土壤微生物数量、放线菌比例及土壤酶活性明显大于自根苗。研究表明，嫁接辣椒根系发达，根系活力增强，根际土壤放线菌比例增加及酶活性提高是其青枯病抗性增强的重要原因。

Abstract:In order to elucidate the mechanism of bacterial wilt resistance in grafted pepper (Capsicum annuum L.),Changes of root characteristics of grafted (‘Xinfeng 2’ scion grafted onto ‘Weishi’) and own-root plants (‘Xinfeng 2’,control) of pepper,quantity of microorganism and enzyme activities in rhizosphere soil were investigated by manual inoculation.The results showed that the root weight,total length,volume,surface area,root tips and forks,root activity,actinomyces quantity and ratio,and activities of polyphenol oxidase (PPO),peroxidase (POD) and dehydrogenase in grafted peppers increased significantly compared with those of control before inoculation.After inoculation,grafted plants showed a less damage in root than that of control plants.Grafted peppers had significant higher root weight,total length,volume,surface area,root tips and fork,root activity,quantity of microorganism and actinomyces ratio,and soil enzyme activities,in comparison with control.These data indicated that the observed increase in root system,root activity,quantity of microorganism,ratio of actinomyces,and enzyme activities in rhizosphere soil of grafted peppers are main reasons of enhancement of bacterial wilt resistance.

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