Fungal endophyte <i>Phomopsis liquidambari</i> B3 enriches the diversity of nodular culturable endophytic bacteria associated with continuous cropping of peanut

<p>Previously, the application of the fungal endophyte <i>Phomopsis liquidambari</i> B3 exhibited notable effect in alleviating soil obstacles caused by continuous cropping of peanut. It was supposed that <i>P. liquidambari</i> B3 could enhance the efficiency of nodulation and nitrogen fixation by enriching the diversity of nodular endophytic bacteria under continous monocropping system. To verify this hypothesis, a pot experiment was conducted under natural conditions. Four treatments were set as follow: discontinuous cropping soil (NS), continuous cropping soil (CK), continuous cropping soil inoculate with actived <i>P. liquidambari</i> B3 (CSB3), and continuous cropping soil inoculate with sterilized <i>P. liquidambari</i> B3 (CSIB3). As a result, a total of 120 isolates were obtained. Our study clearly declared that the addition of fungal endophyte effectively enriched the genetic diversity and the community composition in CSB3. In contrast, a low genetic diversity level and simplex community structure were exhibited in CK and CSIB3. Meanwhile, the positive percentage rate and corresponding community composition of the plant growth-promoting isolates in NS and CSB3 were larger and more abundant than the other. This is the first time to describe the effects of fungal endophytes on the diversity of the nodular culturable endophytic bacteria associated with continuous cropping of peanut.</p>