Maize/peanut intercropping system shows the significant yield advantage. Soil microbes play major roles in soil nutrient cycling and were affected by intercropping plants. This experiment was carried out to evaluate the changing of rhizosphere microbial community composition, and the relationship between microbial community and soil enzymatic activities, soil nutrients in maize/peanut intercropping system under the following three treatments： maize （Zea mays L.） and peanut （Arachis hypogaea L.） were intercropped without any separation （NS）, by half separation （HS） using a nylon net （50 μm） and complete separation （CS） by using a plastic sheet, respectively. The soil microbial communities were assessed by phospholipid fatty acid （PLFA）. We found that soil available nutrients （available nitrogen （Avail N） and available phosphorus （Avail P）） and enzymatic activities （soil urase and phosphomonoesterase） in both crops were improved in NS and HS treatments as compared to CS. Both bacterial and fungal biomasses in both crops were increased in NS followed by HS. Furthermore, Gram-positive bacteria （G＋） in maize soils were significant higher in NS and HS than CS, while the Gram-negative （G-） was significant higher in peanut soil. The ratio of normal saturated to monounsaturated PLFAs was significantly higher in rhizosphere of peanut under CS treatment than in any other treatments, which is an indicator of nutrient stress. Redundancy analysis and cluster analysis of PLFA showed rhizospheric microbial community of NS and HS of both plants tended to be consistent. The urase and Avail N were higher in NS and HS of both plants and positively correlated with bacteria, fungi （F） and total PLFAs, while negatively correlated with G＋/G- and NS/MS. The findings suggest that belowground interactions in maize/peanut intercropping system play important roles in changing the soil microbial composition and the dominant microbial species, which was closely related with the imp
地黄种植过程中存在严重的连作障碍问题,连作导致块根无法正常膨大、产量品质下降、土传病害严重等。本研究以正、重茬地黄块根为试验材料,通过差异蛋白质组学技术分析连作下地黄块根蛋白质表达谱变化,并进一步采用q RT-PCR技术对锁定的差异蛋白质表达量变化进行验证分析。研究结果发现,连作导致与块根重要生理代谢过程和主要成分合成相关的蛋白质都下调表达,与蛋白质折叠相关的伴侣素(chaperonin)在重茬地黄块根中全部下调表达;连作下与胁迫响应、抵御相关的蛋白质(如pathogenesis-related protein 10,cytochrome P450,Type IIIa membrane protein cp-wap13等)均上调表达。q RT-PCR定量分析证实重茬地黄块根中PR-10基因表达量显著高于正茬地黄;PR-10基因在尖孢镰刀菌病原菌侵染下能够明显被诱导表达,表达量随着侵染时间的增加而逐渐升高,验证了差异蛋白质组学分析的结果。可见连作胁迫对地黄块根蛋白质表达谱有显著影响,导致蛋白质表达紊乱,连作植株生理代谢过程异常,碳水化合物和能量代谢缓慢,产生连作障碍效应。
