Lab Notes 02-September 29th, 2015 Crop Improvement

How do a bunch of A, T, G and C’s help crop improvement?

 

It can be hard to see how a huge string of DNA sequence can actually allow scientists to develop crops with better heat and drought tolerance. A genome is an essential foundation of knowledge for breeders, farmers, and crop scientists to develop improved lines. What do we mean by improved? We’re talking crops that require less water, can withstand more heat, can continue growth in salt-laden soils- all aspects of drought in agricultural regions. We will use the genome of Sporobolus nealleyi to identify what makes it unique. These unique elements will be analyzed using existing tools to identify what may control the incredible gypsum-endemism and extreme drought tolerance in this species. The final result is generation of candidate genes that can be introduced to- or endogenously modified in crops like corn, rice and wheat to impact drought and heat tolerance.

How will this project help future researchers in improvement of grains’ drought and heat tolerance?

Thousands of researchers around the world are working to identify unique elements in crops’- and related plants’ genomes that can enable improvement of drought and heat stress. These elements are often called markers. Markers give breeders and researchers a toolset to predict the behavior of a plant generated from crosses. It uses what nature has successfully done for millennia. Breeders can utilize markers to accelerate crop improvement through marker-assisted breeding. Instead of growing-out all the progeny of a cross, scoring their behavior and culling undesirable individuals, a DNA footprint can be accessed early in their growth. Time and attention is then focused only on those individuals carrying the desirable marker.

Biotechnology is another powerful option available for rapid crop improvement in today’s agricultural field. In severely drought-stricken areas around the world, crops may be so limited for water that they fail to produce adequate grain. In these cases, peoples’ need for caloric intake can trump many other concerns. By identifying candidate genes in Sporobolus nealleyi responsible for its remarkable gypsum endemism and drought tolerance, researchers can identify targets for expression in rice, wheat and corn crops. While generation of a phenotypes found in S. nealleyi may require expression of multiple genes in these crops, significant gains may be achieved with only one (gene). Some studies have identified variable regulation of genes in rice and wheat as those thought to be responsible for the incredible drought tolerance of another Sporobolus species grass- S. stapfianus (a ‘resurrection grass’).

 

Overall, this project will help to generate the knowledge needed for traditional, marker-based breeding and even biotechnology-based approaches to be employed by future researchers to quickly accelerate drought tolerance in some of the world’s most important grain crops. Through these efforts, the project enables more grain to reach more people, particularly in areas that need it most. This eventual pay-off cannot be reached without fundamental knowledge of S. nealleyi’s genome sequence.

My trip to New Mexico will enable sample collection to begin achieving this goal. The longest journey begins with the first step.

--Chris