Comparison of the Endophytic Bacterial Microbiota of Asymptomatic and Symptomatic Ginger Rhizomes During the Activation of Adventitious Bud Development

Abstract

Bacterial infections are the cause of rhizome rot in ginger (Zingiber officinale). Key members of the endophytic microbial community in ginger rhizomes have not been identified and their impact on the decay of rhizomes during the activation of adventitious bud development has not been investigated. High-throughput, 16S rRNA amplicon sequencing and inoculation experiments were used to analyze the microbial diversity, community structure and composition, and the pathogenicity of isolated bacteria. Our results indicated that the composition of the endophytic microbiota underwent a shift during the progression of rhizome rot disease. Enterobacteriaceae and Lachnospiraceae and the bacterial genera, Clostridium, Bacteroides, Acrobacter, Dysgonomonas, Anaerosinus, Pectobacterium, and Lactocossus were relatively abundant in the bacterial community of rhizomes exhibiting bacterial decay symptoms but were also present in asymptomatic rhizomes. The presence of Enterobacteriaceae and Pseudomonadaceae were positively correlated (p=0.83) at the beginning of the sampling period in the symptomatic group, while a positive correlation (p=0.89) was only observed after 20 days in the asymptomatic group. These data indicate that the co-occurrence of Enterobacteriaceae and Pseudomonadaceae may be associated with the development of ginger rot. Bacterial taxa isolated from ginger rhizomes, such as E. cloacae, E. hormaechei, and Pseudomonas putida induced obvious rot symptoms when they were inoculated on ginger rhizomes. Notably, antibiotic-producing bacterial taxa in the Streptococcaceae and Flavobacteriaceae were also relatively abundant in rhizomes with rot and appeared to be linked to the onset of rhizome rot disease. Our results provide important information on the establishment and management of disease in ginger rhizomes.

Pathogenic fungi shape the fungal community, network complexity, and pathogenesis in kiwifruit

“…The fungal flora was more diverse in ND samples than in asymptomatic fruit samples. This finding is similar to the results in our previous that found that during the process of decay development in ginger, the diversity of bacterial communities increased in symptomatic samples (Huang et al, 2022 ). The ability of the four newly identified pathogens to infect mature kiwifruit was also investigated.…”

“…The interaction between a host and its endophytic microbial community is also affected by biological or environmental factors (Brader et al, 2017 ). Our previous study demonstrated that different environmental conditions can result in a shift in the structure of the endophytic microbial community of kiwifruit that either prevents (Sui et al, 2021 ) or promotes disease (Huang et al, 2022 ). The introduction of fungal pathogens through natural or artificial (inoculation) means could greatly increase the potential for a shift in the endophytic fungal community of fruit (Yin et al, 2023 ).…”

“…In kiwifruit, high‐throughput, amplicon sequencing has been used to investigate postharvest disease control. Amplicon sequencing also revealed that the application of the biocontrol yeast, Wickerhamomyces anomalus on kiwifruit altered microbial community composition and decreased the abundance of fungal pathogens, resulting in a decreased level of postharvest disease (Huang et al, 2022 ). In the present study, the epidermal (peel) tissue from symptomatic with brown spot and asymptomatic kiwifruit were used to explore, isolate and identify potential new pathogens.…”

Environmental legacy effects impact maize growth and microbiome assembly under drought stress

“…Less is known about the relevance of Streptococcaceae to plant growth. In Zingiber officinale , this family was significantly enriched in rhizomes with advanced stages of soft rot (Huang et al 2022). However, Streptococcaceae is prevalent in soil and plants (Chuah et al 2016; Wang et al 2021), typically at higher abundance in aerial plant compartments than in the rhizosphere (Minervini et al 2015; Yu et al 2020).…”

“…Less is known about the relevance of Streptococcaceae to plant growth. In Zingiber officinale, this family was significantly enriched in rhizomes with advanced stages of soft rot (Huang et al 2022).…”