Community Analysis of Root- and Tuber-Associated Bacteria in Field-Grown Potato Plants Harboring Different Resistance Levels against Common Scab

Abstract

Eight genotypes of potato plants with different resistance levels against common scab were grown in a field infested with Streptomyces turgidiscabies. DNA was extracted from the roots, tubers, and rhizosphere soils of each of the eight genotypes at the flowering stage, and the quantity of S. turgidiscabies genomic DNA was assessed by real-time PCR using a TaqMan probe. The results obtained showed that the different potato genotypes had significant impacts on the population levels of S. turgidiscabies between resistant and susceptible genotypes in the tubers, but not in the roots or rhizosphere soils. Clone analyses of 16S rRNA gene libraries from the eight potato genotypes identified three phyla (Proteobacteria, Firmicutes, and Actinobacteria) as dominant taxa in root and tuber clone libraries, while a clustering analysis identified 391 operational taxonomic units (OTUs) at the species level. Eleven OTUs closely related to Aquicella siphonis, Arthrobacter nicotinovorans, Streptomyces rishiriensis, Rhodococcus baikonurensis, Rhizobium radiobacter, Rhizobium etli, Phyllobacterium myrsinacearum, Paenibacillus pabuli, Paenibacillus alginolyticus, and Bacillus halmapalus were detected in the root or tuber libraries of all the potato genotypes examined. Furthermore, an abundance of OTUs related to Aquicella and Rhodococcus was observed in the rhizospheres of resistant and susceptible potato genotypes, respectively. Based on this ecological information, an efficient survey may be conducted for biological agents from the potato rhizosphere.

Shared and host‐specific microbiome diversity and functioning of grapevine and accompanying weed plants

“…The overall ubiquitous presence of Arthrobacter strains could be due to their extraordinary traits such as enormous nutritional versatility, high resistance to desiccation and starvation (Hagedorn and Holt, 1975;Cacciari and Lippi, 1987) as the sampling field was characterized by high salinity and low water content. Our results are consistent with the findings of Kobayashi et al (2015), who found Arthrobacter nicotinovorans to be frequently associated with roots and tubers of different potato cultivars. Arthrobacter species are known to be involved in the biodegradation of organic matter (Cacciari and Lippi, 1987) and may produce antibiotics (Kamigiri et al, 1996).…”

“…Our results are consistent with the findings of Kobayashi et al . (), who found Arthrobacter nicotinovorans to be frequently associated with roots and tubers of different potato cultivars. Arthrobacter species are known to be involved in the biodegradation of organic matter (Cacciari and Lippi, ) and may produce antibiotics (Kamigiri et al ., ).…”

Diversity of rhizosphere and endophytic fungi in Atractylodes macrocephala during continuous cropping

“…The soil which was loosely attached to the roots was removed by gentle shaking. Tightly bound soil was considered rhizospheric and was obtained by firmly shaking the root system in a sterile plastic bag (Kobayashi et al, 2015;Tan et al, 2017b). The rhizospheric soil samples were thoroughly mixed, and randomly divided into three subsamples, as described previously (Yu et al, 2019).…”

Enzymatic hydrolysis by transition-metal-dependent nucleophilic aromatic substitution

“…There is growing awareness of the potential use of rhizospheric or endophytic bacteria as biocontrol agents to enhance resistance to plant pathogens 8–10 , including Streptomyces scabies 11 , which causes potato scab 12 , an agricultural disease of worldwide economic importance 13 . The primary phytotoxin, thaxtomin, is a family of 5-nitrotryptophan-containing cyclic dipeptides.…”