Effects of different patterns of tillage combined with straw returning on endophytic bacterial diversity in maize

Abstract:

[Objective] To reveal the composition and functions of endophytic bacterial communities in maize under different patterns of tillage combined with straw returning in the Tumochuan Plain, identify the endophytic bacterial resources that promote maize straw degradation under different patterns, and lay a foundation for the selective isolation, cultivation, and functional verification. [Methods] We employed Illumina MiSeq high-throughput sequencing to compare the diversity and community structure of endophytes during the mature stage of maize under different patterns of tillage combined with straw returning in the continuous positioning experiment in the irrigation area of Tumochuan Plain, Inner Mongolia Autonomous Region. [Results] No tillage and deep tillage demonstrated significant effects on the endophytic bacterial diversity of maize. Tillage methods exerted stronger effects on the composition and structure of endophytic bacterial community than straw returning. The structures of endophytic bacterial communities in maize can be classified into two categories: no tillage combined with straw returning and the other seven patterns. The dominant endophytic bacterial genera shared by the nine patterns of tillage combined with straw returning were Pseudomonas, unclassified_f__Enterobacteriaceae, Pantoea, Raoultella, and Rahnella1. Straw returning increased the abundance of Raoultella and unclassified_f__ Enterobacteriaceae. [Conclusion] Different tillage practices alter the diversity, composition, and structure of endophytic bacterial community in maize. Straw returning can increase the relative abundance of Raoultella and Lactococcus, which have positive effects on the degradation of maize straw.