U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 Wind Erosion and Water Conservation Research: Lubbock, TX
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                                    Software
                People

                    Staff Listing
                                    CareersSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Plains Area Lubbock, Texas Cropping Systems Research Laboratory Wind Erosion and Water Conservation Research Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            KUMAR, SHASI - TTUitem
                                            DOWD, SCOT - RESEARCH & TESTING LABitem
                                            Acosta-Martinez, Veronicaitem
                                            McMichael, Bobbieitem
                                            JETER, R - TTUitem
                                            SAN FRANCISCO, MICHAEL - TTUitem
                                            ZAK, JOHN - TTU
  Submitted to: American Society of Microbiologists Abstracts
                                    Publication Type: Abstract Only
                                    Publication Acceptance Date: 11/9/2008
                                    Publication  Date: 11/11/2008
                                    Citation: Kumar, S., Dowd, S., Acosta Martinez, V., McMichael, B.L., Jeter, R.M., San Francisco, M., Zak, J. 2008. Bacterial diversity in peanut rhizosphere in a semi-arid climate: impacts of nitrogen fertilization. South Central Branches of the American Society of Microbiologists. November 9-11, 2008.  Austin, Texas.Interpretive Summary:
                                Technical Abstract: Rhizobacteria can play important roles in agronomic ecosystems impacting nutrient availability, nutrient uptake, and drought responses of plants in many cropping systems.  The ability of rhizosphere bacteria to impact plant growth can be negatively impacted through the application of nitrogen fertilizer, which can alter soil microbial diversity. In this study we analyzed the effect of nitrogen fertilizer on bacterial diversity of the peanut rhizosphere in semi-arid west Texas. The treatment consisted of 35 lb/acre (39.23 kg/ha) of ammonium nitrate added at the beginning of the growing season. Plants in control and fertilizer treatment plots were grown in each of two different tillage soils (stripped and conventional-where the previous crop residue was removed) and with no water stress.  Soil was collected over a 5-month period (post-seedling stage) from the rhizosphere of peanut plants. DNA prepared from these samples was amplified using bacterial universal 16S-rRNA-encoding gene primers, and the products were subjected to pyrosequencing. Rarefaction analysis was used to determine the influence of added nitrogen on bacterial diversity as defined by Operational Taxonomic Units (OTUs). The number of OTUs was consistently lower in all the soil samples treated with nitrogen fertilizer. Nitrogen fertilization increased the dominance of certain bacteria thereby reducing overall bacterial diversity by suppressing bacteria that could not take advantage of the additional nitrogen. The most dominant bacterial class observed in this study was the actinobacteria (treatment as well as control).


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov