Working hard on the next generation of waxy corn hybrids

DuPont Pioneer is committed to helping growers produce more and better food, with fewer resources, through improved plant genetics. They have been fulfilling this mission over the past 90 years, beginning with the commercialization of the first corn hybrids in the 1920s, co-developing one of the first biotech traits with Dow AgroSciences in the 1990s. Now, DuPont Pioneer is an early adopter of one of the most exciting biological breakthroughs of the 21st century — CRISPR-Cas as an advanced plant breeding technology.

According to Neal Gutterson, vice-president, Research and Development at DuPont Pioneer, they operate in more than 90 countries and work in crops like corn, soybeans, canola, sunflower, rice, wheat, sorghum and pearl millet.

DuPont Pioneer is at the forefront of the development of new plant varieties, based on some of the so-called new breeding methods. What was the motivation of DuPont Pioneer to go for these techniques?

“Rapid population growth coupled with limited resources and climate change requires innovation to keep pace at a similar rate,” Gutterson says. “The superior properties of CRISPR-Cas over previous generations of genome editing tools is expected to help our scientists to develop innovative and sustainable solutions for growers similar to those realized through conventional plant breeding practices, but with even greater quality and accuracy and with more efficient development timelines.”

DuPont Pioneer is working toward bringing a next generation of waxy corn hybrids developed with CRISPR-Cas advanced breeding to the U.S. market by the end of this decade (pending field trials and regulatory reviews). Waxy corn produces a high amylopectin starch content, which is milled for a number of everyday consumer food and non-food uses including for processed foods, adhesives, and high-gloss paper. Gutterson says a limited amount of U.S. waxy corn grain goes for export or for feed in the livestock, dairy, and poultry industries.

“Current waxy corn products do not yield as well as equivalent non-waxy corn hybrids. This is partly due to the origin of the native waxy characteristic from a very old corn variety with inferior yield characteristics, which causes significant and variable impacts on yield (three to 10 per cent average, but also highly variable from season to season). Additionally, it is very time-consuming to introduce the waxy characteristic from one inbred into another through traditional backcrossing methods, which translates to a two to three-year time lag from the launch of new non-waxy commercial hybrids to the waxy versions of those same hybrids.”

Gutterson said the development of the next generation of waxy corn hybrids through CRISPR-Cas advanced breeding introduces the native waxy characteristic directly in elite genetics, dramatically improving the efficiency of the product development cycle and is expected to provide customers with a higher-yielding product on par with non-waxy hybrids.

“With 90 years of corn breeding knowledge, it was natural for us to use our understanding of the biology of corn for our first commercial product using this innovation in breeding,” he explained. “We intend to continue to develop seed products with CRISPR-Cas advanced breeding technology and have a number of product concepts underway focused on disease resistance, drought tolerance and improved hybrid systems. The technology has applicability for all Pioneer crops of interest.”

How does Gutterson expect new breeding methods like CRISPR-Cas will be regulated?

“We are monitoring the development of the global regulatory policies for products of CRISPR-Cas technology and are in regular consultation with global regulatory bodies and government agencies. We continue to encourage a science-based approach and believe that regulatory oversight should focus on the characteristics of the product — not the process by which it is created.”

Gutterson explained the latest plant breeding methods should not be differentially regulated if they are similar or indistinguishable from varieties that could have been produced through earlier breeding methods.

Innovation and Technological Advances

Gutterson explained what is needed to promote the necessary societal acceptance for this type of innovation.

“Public trust and the social license for applications of plant breeding innovations will only be achieved through open, transparent and timely communication. We will be launching a microsite dedicated to CRISPR-Cas early this year as one way to provide access to information about our responsible development and application of the technology.”

To unlock the potential of these technological advances, Gutterson believes the true value of plant breeding innovations like CRISPR-Cas will only be achieved through active engagement and collaboration with customers, academia, governments, NGOs and public research institutes to develop new solutions to the toughest agricultural challenges globally.

“As an example, Pioneer and the International Maize and Wheat Improvement Center (CIMMYT) have formed a public/private partnership to jointly develop improved crops using CRISPR-Cas advanced plant breeding to address the needs of smallholder farmers around the world. A range of potential product targets are under consideration by the newly formed Pioneer-CIMMYT Steering Committee. The first project will apply CRISPR-Cas to address the devastating maize lethal necrosis (MLN) disease in sub-Saharan Africa.

“Pioneer welcomes the opportunity to collaborate with others to realize the full potential of the CRISPR-Cas advanced breeding technology in developing innovative solutions for production agriculture and society.”