Effect of Breeding and Genetic Manipulation on the Microbiome Surrounding Maize Roots.

Effect of Breeding and Genetic Manipulation on the Microbiome surrounding Maize Roots.

Noortje Notenbaert and Charles W. Rice

Department of Agronomy, Kansas State University, Manhattan, KS 66506, USA

Maize (Zea mays L. ssp. mays) is a major staple crop which has undergone extensive breeding and genetic modification, especially in the last 50 years. The objective of this study was to examine the impact of breeding for aboveground traits on the microbial community of surrounding soil. This study examined the microbial communities between two older (B73 and B73xMo17) and two newer maize cultivars (DKC63-55 and DKC64-69) to determine changes in the plants’ ability to attract beneficial microbes. We hypothesized that older cultivars would be able to form better relationships with bacteria and fungi compared to the newer cultivars, especially in low phosphorus (P) soil. It was also expected that the greater the difference between the cultivars, the more distinct their soil microbiome. A field experiment was conducted from which samples were taken at V6, VT, and R1 as well as a greenhouse experiment from which samples were taken three weeks after emergence. Analyses consisted of root staining to test for mycorrhizal relationships, Phospholipid Fatty Acid (PLFA) analysis for microbial communities, total plant and root biomass to understand physical differences, and plant nutrient content by dry combustion. Results are pending.