,The goal of the National Microbial Germplasm Program is to ensure that the genetic diversity of agriculturally important microorganisms is maintained to enhance and increase agricultural efficiency and profitability. The program collects, authenticates, and characterizes potentially useful microbial germplasm; preserves microbial genetic diversity; and facilitates distribution and utilization of microbial germplasm for research and industry.,The Agricultural Research Service maintains several microbial germplasm collections including:,

,The ARS Culture Collection is one of the largest public collections of microorganisms in the world, containing approximately 93,000 strains of bacteria and fungi. The collection is split into subcollections of molds, prokaryotes, and yeasts. In addition, the online catalog is searchable by genus, species, subvar type, and subspecies.,The collection is housed within the Mycotoxin Prevention and Applied Microbiology Research Unit at the National Center for Agricultural Utilization Research in Peoria, Illinois. The scientists and staff of the ARS Culture Collection conduct and facilitate microbiological research that advances agricultural production, food safety, public health, and economic development. These goals are pursued through in-house research that improves understanding and utilization of microbiological diversity and through efforts to enhance the value and accessibility of microbial accessions in the Agricultural Research Service Culture Collection.,

,During symbiosis, C that rhizobia respire to power N fixation can be stored as polyhydroxybutyrate (PHB), shown to support rhizobia survival under laboratory starvation. We collected soil in 2015 from four replicate plots per treatment in two long-term experiments at Waseca, Minnesota. Treatments differed in the intervals between soybean (Glycine max (L.) Merr.) hosts. We measured PHB accumulation in eight nodules per plant from four soybean (cv. ‘MN0095’) trap plants per soil sample. Trap plants were arranged in a greenhouse, common-garden experiment, and PHB accumulation was measured using flow cytometry. Treatments sampled after long intervals without soybean (greater than two years) showed a greater relative abundance of high-PHB strains. Treatments sampled after the first year of soybean following five years of a non-host crop showed a decreased relative abundance of high-PHB strains, compared to treatments sampled after long intervals without soybean. The latter result is consistent with the hypothesis (not tested directly here) that some high-PHB strains were “sanctioned” by plants as less-beneficial. Our results suggest that rhizobia strains with the tendency to allocate more C to N fixation at the expense of PHB accumulation may be less likely to persist where soybean is grown infrequently or where soil conditions make PHB particularly valuable. However, with typical two-year rotations in Minnesota, differences in PHB storage are unlikely to have a major effect on the relative survival of strains.,See README.md for a detailed description of data files and scripts.,

,This database server is supported in fulfilment of the research mission of the Mycotoxin Prevention and Applied Microbiology Research Unit at the National Center for Agricultural Utilization Research in Peoria, Illinois. The linked website provides access to gene sequence databases for various groups of microorganisms, such as Streptomyces species or Aspergillus species and their relatives, that are the product of ARS research programs. The sequence databases are organized in the BIGSdb (Bacterial Isolate Genomic Sequence Database) software package developed by Keith Jolley and Martin Maiden at Oxford University.,

This project facilitated the implementation of a multiyear project to understand how climate variability and management practices influence soil microbial and nutrient dynamics within a no-till cotton production system with stubble management. Three fields at the R.N. Hooper farm in Petersburgh, TX were used for this project and continue to be monitored with funds from Cotton Inc. The three fields are center-pivot irrigated to compensate for rainfall variability as needed and depending upon water availability. The three fields were planted into the following crops for 2017 : Field 1 – corn following cotton; Field 2 – cotton following corn, and Field 3 – Wheat/mixed summer cover following wheat. The sizes of the three no-till and fields are: Field 1: 78.48 m in diameter, Field 2: 971.29 m in diameter, and Field 3: 781.1 m in diameter. The conventional field was located a few miles from the no-till fields and was also center-pivot irrigated when needed and managed as a tilled cotton production system with a corn -cotton rotations for the past five years. The no-tilled fields have been rotated among, cotton, corn, winter wheat and summer cover (when possible) for the past five years. Within each system we set soil moisture and temperatures sensors at the surface and at 15 cm depth and monitored microbial and nutrient dynamics across the year. Fields were instrumented in March 2017 and were monitored continuously except for harvesting and planting periods. Soil samples were taken initially in May 2017 and then each month from six plots established across each field. The following parameters were evaluated at each location and within each field: % soil moisture, Microbial Biomass Carbon, extractable levels of NO3-N and NH4-N and % Soil Organic Matter.