The invention discloses a layered gel culture technology constructed by using environmental extracts, and belongs to the field of environmental
microorganism culture. According to the technology, an environmental sample is separated into a particle phase and a
liquid phase through
water extraction, the particle phase and the
liquid phase are respectively prepared into a lower-layer
solid-
phase matrix and an upper-layer gel phase with gel (preferably
agar), a vertical
nutrition /
signal slow-release gradient is formed in a culture dish, and particle attachment sites are provided; and inoculating the environmental microorganisms on the upper layer or the surface for culture. Compared with
nutrient agar or extremely simple water
agar, the method has the advantages that more bacterial colonies and higher distinguishable form number can be obtained under the repeatable condition, and the
community diversity and the OTU / ASV overlapping degree with an original sample are improved; rare / slow-growing groups can be stably separated, and subsequent 16S / metagenome analysis and agar block bacteriostasis
primary screening are facilitated. Meanwhile, the invention provides a corresponding culture medium composition and a kit / prefabricated layered culture dish. According to the scheme, operation is easy and convenient, parameters can be standardized, and the method is suitable for isolated culture and ecological function research of environmental samples such as soil, sediments and low-
solid water samples.