Organic mulch can suppress litchi downy blight through modification of soil microbial community structure and functional potentials

Abstract

Background Organic mulch is an important management practice in agricultural production to improve soil quality, control crop pests and diseases and increase the biodiversity of soil microecosystem. However, the information about soil microbial diversity and composition in litchi plantation response to organic mulch and its attribution to litchi downy blight severity was limited. This study aimed to investigate the effect of organic mulch on litchi downy blight, and evaluate the biodiversity and antimicrobial potential of soil microbial community of litchi plantation soils under organic mulch. Results Organic mulch could significantly suppress the disease incidence in the litchi plantation, and with a reduction of 37.74% to 85.66%. As a result of high-throughput 16S rRNA and ITS rDNA gene illumine sequencing, significantly higher bacterial and fungal community diversity indexes were found in organic mulch soils, the relative abundance of norank f norank o Vicinamibacterales, norank f Vicinamibacteraceae, norank f Xanthobacteraceae, Unclassified c sordariomycetes, Aspergillus and Thermomyces were significant more than that in control soils. Isolation and analysis of antagonistic microorganism showed that 29 antagonistic bacteria strains and 37 antagonistic fungi strains were unique for mulching soils. Conclusions Thus, we believe that organic mulch has a positive regulatory effect on the litchi downy blight and the soil microbial communities, and so, is more suitable for litchi plantation.

Effect of biochar and bioorganic fertilizer on the microbial diversity in the rhizosphere soil of Sesbania cannabina in saline-alkaline soil

“…However, in the current study, Xanthobacteraceae was positively correlated with OC, and was enriched in FB1_BOF. This may be consistent with the results of Xu et al (2022) , who reported that Xanthobacteraceae significantly increased in response to organic mulch. Streptomyces , an important group of soil bacteria belonging to the actinomycetes family, are widely reported in the literature for their plant growth-promoting rhizobacteria potential ( Nassar et al, 2003 ; El-Tarabily, 2008 ).…”

Health of shallot bulbs planted with mycorrhizal applications and several types of mulch in moler disease conducive land

“…Ramirez et al reported that organic mulch suppresses avocado infection by Phythophthora cinnamoni [31]. In comparison, Xu et al said that mulch suppresses litchi downy blight caused by Peronophythora litchii by increasing the diversity of soil microbial communities [32]. A similar study by Zhang et al showed that organic mulch increased the diversity of soil microbes such as groups of bacteria Proteobacteria, Actinobacteria, Acidobacteria, and Chloroflex and groups of fungi Ascomycota, Mortierellomycota and Basidiomycota became dominant [33].…”

How Organic Mulching Influences the Soil Bacterial Community Structure and Function in Urban Forests

“…In this study, the relative abundances of K-strategists were significantly and positively correlated with soil nutrient contents, while the relative abundances of r-strategists had a negative relationship with soil nutrient availability. Acidobacteria is considered to have extensive metabolic and genetic functions [ 34 ]. Jiang et al [ 16 ] pointed out that Acidobacteria had numerous subdivisions, and different subdivisions showed varied correlations with soil nutrients.…”