Location: Water Management and Systems Research
Project Number: 3012-13210-001-009-I
Project Type: Interagency Reimbursable Agreement
Start Date: Aug 10, 2020
End Date: Sep 30, 2022
In this project, we will test the ability of selected soil microbiomes to improve field crop performance under drought by shifting stomatal closure point (SCP), the tissue desiccation limit at which plants close the stomata under drought, and improving crop water use efficiency.
The soil for the first generation of soil microbiome will be collected from a Colorado field experiment on maize that included drought and N-fertilization treatments. This soil will be used to inoculate plants growing in greenhouse pots. Subsequent generations will take 10% of the best of each treatment and pool the soil microbiomes to create an inoculum for further rounds of selections. We will produce an inoculum by creating a microbiome slurry from the rhizosphere microbiome diluted with sterilized, deionized water, and apply at least 50 ml per pot after seed germination. The final stabilized microbiomes will be tested in subplots of a USDA-ARS field experiment. In the first year of the field tests, we will focus on testing inoculation methods and amount of inoculant needed. Active and inactive inoculum will be spread in in a ring around 12 plants in subplots for each microbiome per field varying in two levels of water availability and N fertilization (4 field treatments: full irrigation, full N; full irrigation, low N; dryland, full N; dryland, low N). The focus of the field experiments in the second year of field tests will be determined based on results from the first year with the goal of increasing to 3 replicates per microbiome in field conditions.