Research interests
The Wallace Lab focuses on using quantitative genetics, genomics, bioinformatics, and statistics to understand complex traits in crop plants. Most of our own research focuses on the interactions between plants, especially maize (corn), and the microorganisms that live on and inside it. We also have several fruitful collaborations with other labs that let us work on more traditional traits (yield, nutrient use, etc.) in other crops.
Maize Aerial Roots and Nitrogen Fixation
Maize produces above-ground (“aerial”) roots to help stabilize the plant, but some varieties also make large amounts of gooey “mucilage” on them. Nitrogen-fixing microbes can grow in this mucilage and provide usable nitrogen to the plant, a process that has been exploited by indigenous farmers in Oaxaca, Mexico, for centuries. We are collaborating with nitrogen-fixing experts at the University of Wisconsin-Madison to understand how this partnership works and how it can be harnessed for modern maize production
Publications
Maize-Microbe Interactions
The microbiome refers to the collection of microbes (mostly bacteria and fungi) living on and inside an organism. One of our main research foci is looking at how genetic variation in crops changes how they interact with microbes, using maize as a model organism. Maize is ideal for this because of its great genetic diversity and importance to global food security.
Publications
- Gene-by-environment interaction is a major driver of maize stalk communities (PREPRINT)
- Sampling & Analysis of the Maize Microbiome (Protocol collection)
- Living mulch promotes a more balanced soil community
- Effects of inbreeding maize microbial communities
- Genetic variation among maize varieties changes their interactions with beneficial endophytes
- Review of maize endophytes in general and also seed endophytes in particular
Tall fescue and Epichloë Endophytes
Tall Fescue (Festuca arundinacea) is a in important grass for both grazing and turf in the southeastern United States. Much of the tall fescue in the US is infected with a fungal endophyte, Epichloë coenophiala, that provides great stress resistance but can also harm grazing livestock. We study this symbiosis as a model of a strongly beneficial plant-microbe interaction to learn how the host plant can affect growth and toxin production in its endophyte.
Publications
Crop Genomics
Quantiative genetics deals with traits that are controlled by many (sometimes thousands) of individual genes. We use advanced statistical and computational methods to tease apart the relationship between plant phenotypes and the genes controlling them. These results can be used by breeders to create varieties with better disease resistance, lower water or fertilizer requirements, and/or improved nutrition. Most of these projects are done as collaborators with other labs.
Publications
- Population structure and genetic mapping in proso millet, with M. Vetriventham (ICRISAT)
- kGWASflow: A pipeline for kmers-based GWAS
- Mining Utricularia gibba for insulator-like elements for genetic engineering, with Wayne Parrott (University of Georgia)
- Genomic selection for peanut aflatoxin resistance, with Peggy Ozias-Akins (University of Georgia)
- A new maize lesion mimic trait, with Seth Murray (Texas A&M)
- Cotton trait mapping, with Andy Patterson (University of Georgia)
- Sorghum aphid resistance, with Som Punnuri (Fort Valley State University)
- Peanut genetic diversity, with Nino Brown (University of Georgia)
- Genetic diversity among commerical CBD hemp (Cannabis sativa) varieties
- Fonio (Digitaria exilis) genome and genetic diversity
- Population analysis in barnyard millet, foxtail millet, and several minor millets
- Mapping disease resistance and fertility restoration in pearl millet
Other Projects
This section is currently under construction