Three soil conditioners were prepared from granulated food waste and decomposed cattle manure combined with desulfurization gypsum, coal gangue, and maifanite, respectively. Field trials were conducted in the saline field growing Cabernet Sauvignon. The effects of soil conditioners on rhizospheric bacterial communities were studied, with the aim of providing a scientific basis for soil amelioration and restoration. Five treatments were designed, including the control (T1), conventional fertilization (T2), reduced chemical fertilization+organic matter-based soil conditioner with calcium additives (T3), reduced chemical fertilization+organic matter-based soil conditioner with silica additives (T4), and reduced chemical fertilization+organic matter-based soil conditioner with magnesium additives (T5), each with three replications. The results indicated that soil conditioners improved the rhizospheric nutrients, yield, and quality of grape (P<0.05), increased relative abundance of Proteobacteria by 17.32%-23.37%, decreased relative abundance of unidentified_Bacteria and Acidobacteriota by 4.22%-28.42% and 20.88%-35.81%, respectively. The bacterial community composition and diversity were different between treatments. Function analysis showed that the expression levels of the genes involved in chromosome and protein synthesis, mRNA biosynthesis, and glyoxylate and dicarboxylate metabolism were up-regulated in the treatments with soil conditioners. The correlation analysis revealed that multiple environmental factors affected the alpha diversity of rhizospheric bacterial communities, and some bacterial taxa were closely related to the grape yield and quality. It is concluded that soil conditioners can effectively alter rhizosphere nutrient levels and bacterial community structures and functions. T5 treatment outperforms other treatments in improving the physico-chemical and biological characteristics of rhizosphere, and the yield, and quality of grape. It has potential for application, and provides an important basis for development of new-type soil conditioners.
Soil Microbiology ; Rhizosphere ; Soil/chemistry* ; Vitis/microbiology* ; Fertilizers ; Bacteria/growth & development* ; Cattle ; Manure ; Animals

In order to determine the changes of bacterial community structure and function in the early, middle and late stage of aerobic composting of chicken manure, high-throughput sequencing and bioinformatics methods were used to determine and analyze the 16S rRNA sequence of samples at different stages of composting. Wayne analysis showed that most of the bacterial OTUs in the three composting stages were the same, and only about 10% of the operational taxonomic units (OTUs) showed stage specificity. The diversity indexes including Ace, Chao1 and Simpson showed a trend of increasing at first, followed by decreasing. However, there was no significant difference among different composting stages (P < 0.05). The dominant bacteria groups in three composting stages were analyzed at the phylum and genus levels. The dominant bacteria phyla at three composting stages were the same, but the abundances were different. LEfSe (line discriminant analysis (LDA) effect size) method was used to analyze the bacterial biological markers with statistical differences among three stages of composting. From the phylum to genus level, there were 49 markers with significant differences among different groups. The markers included 12 species, 13 genera, 12 families, 8 orders, 1 boundary, and 1 phylum. The most biomarkers were detected at early stage while the least biomarkers were detected at late stage. The microbial diversity was analyzed at the functional pathway level. The function diversity was the highest in the early stage of composting. Following the composting, the microbial function was enriched relatively while the diversity decreased. This study provides theoretical support and technical guidance for the regulation of livestock manure aerobic composting process.
Animals ; Manure/microbiology* ; Chickens/genetics* ; Composting ; RNA, Ribosomal, 16S/genetics* ; Soil ; Bacteria/genetics*