Comparative Analyses of Soil Bacterial Colonies of Two Types of Chinese Ginger after a Major Flood Disaster

Ginger, an important cash crop, has been cultivated for thousands of years in China. However, comparative studies on soil bacterial communities of Chinese ginger varieties, especially after flooding, are lacking. Here, we comprehensively compared the bacterial communities of two types of ginger soils from four different locations. Surprisingly, the 100-year flood (20 July 2021, in Henan, China) did not significantly affect the soil bacterial composition compared with previous reports. In contrast, flooding may have brought in nutrients and promoted the propagation of eutrophic bacteria, and Alphaproteobacteria were the most abundant in the Zhangliang region (~25%). However, due to the most severe flooding and inundation, the Zhangliang region, also probably contaminated with polycyclic aromatic hydrocarbons and heavy metals, showed the lowest microbial diversity. Moreover, the geographical location influenced the microbial communities more than did the soil type or ginger variety. These findings help us understand the species and composition of bacteria and infection of ginger after flooding and soaking. Further, the interaction mechanisms underlying these emerging phenomena need to be further investigated. IMPORTANCE There are few comparative studies on the soil bacterial communities of Chinese ginger varieties after flooding. After a 100-year flood (20 July 2021, in Henan, China), we comprehensively compared the bacterial communities of two types of ginger soils from four different locations. Surprisingly, this flood did not significantly affect the soil bacterial composition compared with previous reports. In contrast, it was found that the flooding may have brought in nutrients and promoted the propagation of eutrophic bacteria for the Zhangliang region. However, the flooding had also brought in polycyclic aromatic hydrocarbon and heavy metal contamination. Moreover, we also verified that geographical location influenced the microbial communities more than did the soil type or ginger variety. These findings help us understand the species and composition of bacteria and infection of ginger after flooding and soaking.