Chitin Amendment Increases Soil Suppressiveness toward Plant Pathogens and Modulates the Actinobacterial and Oxalobacteraceal Communities in an Experimental Agricultural Field

Abstract

A long-term experiment on the effect of chitin addition to soil on the suppression of soilborne pathogens was set up and monitored for 8 years in an experimental field, Vredepeel, The Netherlands. Chitinous matter obtained from shrimps was added to soil top layers on two different occasions, and the suppressiveness of soil toward Verticillium dahliae, as well as plant-pathogenic nematodes, was assessed, in addition to analyses of the abundances and community structures of members of the soil microbiota. The data revealed that chitin amendment had raised the suppressiveness of soil, in particular toward Verticillium dahliae, 9 months after the (second) treatment, extending to 2 years following treatment. Moreover, major effects of the added chitin on the soil microbial communities were detected. First, shifts in both the abundances and structures of the chitin-treated soil microbial communities, both of total soil bacteria and fungi, were found. In addition, the abundances and structures of soil actinobacteria and the Oxalobacteraceae were affected by chitin. At the functional gene level, the abundance of specific (family-18 glycoside hydrolase) chitinase genes carried by the soil bacteria also revealed upshifts as a result of the added chitin. The effects of chitin noted for the Oxalobacteraceae were specifically related to significant upshifts in the abundances of the species Duganella violaceinigra and Massilia plicata. These effects of chitin persisted over the time of the experiment.

Screening endophytic actinobacteria with potential antifungal activity against Bipolaris sorokiniana and growth promotion of wheat seedlings

“…Additionally, the production of chitinase and of glucanase was the main mechanism associated with the biocontrol potential of Streptomyces viridodiasticus against Sclerotinia minor (El-Tarabily et al, 2000). Similar observation was also reported in control of Phytophthora fragariae (Valois et al, 1996), Fusarium oxysporum (Singh et al, 1999) and other phytopathogens (Cretoiu et al, 2013).…”

Chitin and chitin-related compounds in plant–fungal interactions

“…The treatment has a long time effect as chitin amendment was found to raise the suppressiveness of soil for as much as two years following treatment. Moreover, during chitin amendment, microbial communities shifted in both the abundances and structures of both of total soil bacteria actinobacteria, Oxalobacteriaceae and fungi, in particular, Verticillium dahliae were recorded (Cretoiu et al 2013). The richness of family-18 glycosyl hydrolase chitinase genes carried by the soil bacteria was also revealed in chitin- (Cretoiu et al 2013) and chitosan-treated soil (Nampally et al 2015).…”

Improving the Rice Performance by Fermented Chitin Waste

“…Therefore, based on this data, P is likely to be an important and limiting nutrient for rice productivity and, since FCW is rich in available P (Table 1), then the addition of FCW to the soil leads to the enhanced rice yield. Chitin-rich material was recently shown to enhance lettuce growth (Muymas et al, 2014), whilst the addition of chitin to the soil was proposed to be a good agricultural practice for plant protection against pathogens and nematodes (Kobayashi et al, 2002;Cretoiu et al, 2013). Application of chitin to the soil could promote soil microbe diversity (Cretoiu et al, 2014).…”