Arbuscular Mycorrhizal Fungi Community Structure in Rhizosphere Soil and Colonization in Root of BADH Transgenic Maize BZ-136 and Receptor Parental Maize

Abstract Betaine aldehyde dehydrogenase (BADH) transgenic maize has a capability to grow under drought and salt stress, yet problems remain about the risk of cropping BADH on symbiotic microbes. A pot experiment was carried out to assess the impact of BADH transgenic maize BZ-136 on arbuscular mycorrhizal fungi (AMF) colonization in plant and community structure in rhizosphere soil compared with that of parental maize Zheng58 in neutral and saline-alkaline soil. Microscope observation found that BZ-136 only had a significant effect on AMF colonization at elongation stage. High-throughput sequencing analysis revealed that the AMF taxonomic composition kept consistency at the genus level between transgenic BZ-136 and non-transgenic parental Zheng58. NMDS analysis verified the slight difference in community structure between BZ-136 and Zheng58 presented a agrotype-dependent pattern. AMF community indices showed that BZ-136 had a higher richness at flowering stage in saline-alkaline soil and had a higher diversity at mature stage in neutral soil. Heatmap analysis also illuminated AMF community structure of transgenic maize at species level was similar to that of non-transgenic maize. In summary, cropping transgenic BADH maize has minor or transient effects on AMF colonization and soil AMF community structure, while agrotype have a stronger effect on AMF community structure.