连作对不同抗性花生品种根系分泌物和土壤中化感物质含量的影响

Effects of continuous cropping on root exudates of different resistance peanut( Arachis hypogaea L. ) varieties and allelochemicals content in soil

采用连续收集法收集到连作障碍抗性较强的大花生品种鲁花11和抗性较差的小花生品种鲁花12不同连作年限苗期和花期的根系分泌物,采用气相色谱-质谱联用的方法鉴定主要成分,并采用液相色谱法对连作花生土壤中酚酸(醛)类化感物质的含量进行了测定。研究结果表明,鲁花11苗期共鉴定出11种根系分泌物成分,花期鉴定出8种。鲁花12根系分泌物苗期比鲁花11少了肉桂酸,花期多了己六醇。连作5年后,鲁花11根系分泌的对羟基苯辛酸的量明显增加,鲁花12根系分泌的长链脂肪酸类物质棕榈酸和硬脂酸以及醇类物质己六醇的量明显增加。两个花生品种连作5年后土壤中酚酸(醛)类化感物质对羟基苯甲酸、邻苯二甲酸、肉桂酸、2,5-二甲基苯甲醛和2,6-二叔丁基苯酚呈现出累积的趋势,鲁花11的积累总量高于鲁花12。连作障碍不同抗性花生品种根系分泌物对连作的响应存在差异,连作会影响到花生根系分泌物的分泌和累积,进而影响到化感作用的强弱。

Root exudates of big peanut（ Arachis hypogaea L.） variety with strong continuous cropping obstacle resistance Luhua 11 and small peanut variety with weak continuous cropping obstacle resistance Luhua 12 secreted during seedling and flowering stages after continuous planting for different years were collected by continuous collection method,and their main components were identified by the method of gas chromatography- mass spectrometry.Contents of phenolic acid（ aldehyde） in peanut continuous cropping soil were determined by using liquid chromatography. Results showed that 11 and 8 kinds of components were identified from the root exudates of Luhua 11 at seedling and flowering stage respectively. Compared with Luhua 11,cinnamic acid was not found in the root exudates of Luhua 12 at seedling stage,and hexanehexol were found at flowering stage additionally. Root secretion of p- Hydroxybenzene phenylmethyloctanoic acid of Luhua 11 increased obviously after continuous cropping for 5years. Luhua 12 root secretion of long chain fatty acid substance palmitic acid and stearic acid and alcohol substance mannite increased significantly after continuous cropping for 5 years. After these 2 varieties of peanut continuous cropping for 5 years,contents of phenolic acids（ aldehyde） allelochemicals p- Hydroxybenzoic acid,phthalic acid,cinnamic acid,2,5- Dimethylbenzaldehyde and 2,6- Di- tert- butylphenol in soil presented a cumulative trend. And the total accumulation of Luhua 11 was greater than that of Luhua 12. The responses of root exudates of different peanut variety with different resistance to continuous cropping were inconsistent. Continuous cropping can affect the secretion and accumulation of peanut root exudates,which affect the strength of the allelopathy.