Assaying the potential autotoxins and microbial community associated with Rehmannia glutinosa replant problems based on its ‘autotoxic circle’

Abstract

Aims This study attempted to elucidate the underlying correlations among replant problems of Rehmannia glutinosa, the autotoxins and microbes within its rootzone soil. Methods Different root-zone soils of R. glutinosa were collected to identify the potential autotoxins, to quantify the phenolic acids' concentration and to analyse the microbial community composition. Bioassay was conducted to assess the autotoxic potential of these samples and candidate autotoxins. Results R. glutinosa autotoxicity was presented within a 20 cm radius of the plant. Concentrations of the phenolic acids were significantly higher within this range. Twenty compounds and 17 microbes emerged in this range after the R. glutinosa cultivation. Further seedling test showed that four selected compounds possessed conspicuous autotoxic activity and a synergistic effect was observed. Moreover, one potential beneficial fungi (99 % similar with Arthrobotrys oligospora) and one potential pathogens (100 % similar with Acremonium sclerotigenum) were identified. Conclusions Our work defined the 'autotoxic circle' of R. glutinosa and identified the corresponding autotoxins and microbes. We suggest that R. glutinosa has various autotoxins and that these autotoxins and specific microbes deserve further investigation to unravel their interaction with R. glutinosa in replant problems' occurrence.

Effects of Continuous Sugar Beet Cropping on Rhizospheric Microbial Communities

“…A class of defensive secondary metabolites that are released by the roots of cereals, such as wheat and maize, were also found to be able to alter root-associated fungal and bacterial communities [41]. In particular, phenolic compounds were reported to be one of the most important secondary metabolites implicated in allelopathy and have been detected in both natural and managed ecosystems [21,42,43]. However, an excessive accumulation of phenolic compounds in the soil ultimately results in toxicity to the plant itself or neighbors [44].…”

Cucumber (Cucumis sativus L.) Seedling Rhizosphere Trichoderma and Fusarium spp. Communities Altered by Vanillic Acid

“…Autotoxicity is an intraspecific allelopathy process through which plants can inhibit their growth or that of their relatives by releasing toxic chemicals into the environment ( Huang et al, 2013 ), as has been observed in both natural and manipulated ecosystems, particularly agroecosystems. According to previous studies, an imbalance in the microbial community structure and the accumulation of soil-borne pathogens induced by autotoxins are the main causes of soil sickness ( Yu et al, 2000 ; Lin et al, 2015 ; Zhang et al, 2016 ). Cucumber is one of the main vegetable crops among greenhouse plants and is planted in up 40% of the greenhouse vegetable-producing area in China; however, soil sickness problems substantially restrict cucumber production ( Yu et al, 2000 ).…”

Identification of Rehmannia glutinosa L. NB-ARC family proteins and their typical changes under consecutive monoculture stress

“…However, phenolic acids are degraded by soil microorganisms within a week in the field (Zhang et al 2010). The addition of phenolic acids caused significant increases in the population of pathogenic microorganisms in plate cultures and field experiments Zhang et al 2016). Allelochemicals of root exudates mediated adverse chemotaxis of rhizospheric microbes (Wu et al 2015;Zhang et al 2013).…”