More than half of the world’s population depends on rice as their staple food, and the U.S. is the world’s fourth largest exporter of this essential commodity. Rice production must increase dramatically and in a sustainable manner to meet the demands of the 21st century. Population pressure, natural resource limitations, changing climate and globalized markets all contribute to the rapidly evolving landscape of agriculture and underscore the importance of agricultural innovation. Advances in genomic science offer new opportunities to address many of the challenges for the future. The rice genome has been sequenced and efforts are underway to understand the relationship between DNA sequence (genotype) and whole plant performance (phenotype). These studies are fundamental to improving the productivity and nutritional value of our crops, as well as the sustainability of our entire agricultural system. In this project, we are evaluating the genetic diversity of rice germplasm, identifying genes and quantitative trait loci (QTLs) associated with complex traits of importance to rice production, examining the function of these genes and their interaction with other genes in critical pathways, tracing their evolutionary history and developing markers for use in molecular breeding. All information generated in my lab is available to the research community and can be accessed through public databases.

I began this work in an effort to improve the efficiency and sustainability of our agricultural systems. I contribute to this goal by developing novel breeding strategies and more productive and resource-efficient plant varieties. I focus on rice because it is one of the world’s most important staple foods and feeds the largest number of people on earth. My program is dedicated to the characterization and productive utilization of underexploited genetic variation that exists in wild and weedy relatives of crop varieties. The human food supply is totally dependent on the availability of crop varieties that are adapted to the environments in which food must be grown. In the fact of growing population pressure, natural resource limitations and climate change throughout the world, we must develop new approaches to variety improvement and crop production if we are to keep pace with demand. Every consumer and every citizen ultimately cares deeply about access to a safe, healthy and abundant supply of food.

First, my lab has developed the vast majority of molecular markers used in rice breeding programs throughout the world today. We are currently developing new, high-throughput SNP detection platforms to improve the efficiency of genotyping. Second, we have imported a large and diverse collection of wild and cultivated Oryza accessions from around the world as the basis for diversity analysis. DNA from young seedlings is used for molecular analysis in our program. Seed from purified stocks are distributed to collaborators in Texas and Arkansas for field, biochemical and physiological evaluation. Third, data from both genotyping and phenotyping is available on our project web site and in public databases and is used as the basis for identifying genes associated with agronomically important characteristics, developing molecular markers for use in breeding, to understand the population structure and evolutionary history of diverse gene pools, and to identify genes from wild species that enhance the yield, disease and pest resistance and abitoic stress tolerance of modern cultivars. In summary, our breeding strategies, improved lines and diversity data are publicly available and are widely used by the international community of breeders, geneticists and germplasm managers to enhance the effectiveness of rice breeding programs, university research and training initiatives throughout the world.

This work impacts rice breeders, rice farmers and the broader community of agricultural researchers in several ways. Major rice breeding programs in the U.S., China, India, Indonesia, Thailand, Vietnam, Korea, and the Philippines are utilizing the molecular markers, breeding lines, breeding strategies and diversity data emerging from my research program. These outputs contribute directly to improving the yield performance, grain quality and stress tolerance of rice varieties around the world. In the U.S., rice breeders use molecular markers developed in my lab to select for genes conferring disease resistance, grain quality and yield performance. In China, the widely planted super-hybrid varieties that enhance yield by ~15-20% were developed using advanced genetic materials and molecular markers from my program. In India, researchers are enhancing the performance of their high-quality, premium rice varieties using marker assisted breeding strategies developed for rice in my program. Overall, the impact of my work can be documented by the fact that virtually every major rice breeding program in the world uses molecular markers and breeding strategies developed in my program, and these new approaches are increasing the efficiency of rice improvement, providing better adapted, more productive and higher quality rice varieties to farmers whose production provides the staple food for almost half of people on earth.

rice diversity