Principles of Plant Genetics and Breeding

BREEDING HYBRID CULTIVARS 337
ducing seed products with these traits onto the marketplace, Pioneer must make sure that these traits are registered within the
country where the products are sold and follow all legal and regulatory guidelines within each market. This also includes following
product stewardship guidelines within product development and educating its grower customers on these rules, so that the
technology is preserved long into the future.
Another application of biotechnology tools is the gene mapping technique. This provides information for direct genetic selection
of the gene combinations in breeding lines. Using this information, researchers make more accurate decisions about which
lines to use in developing new hybrids.
Researchers at Pioneer spend 4–7 years evaluating products in the laboratory and in a wide variety of growing conditions
before new hybrids are released for sale to farmers.
To some extent, plant breeding is a numbers game: the more genetic combinations that are developed and tested, the greater
the odds of developing improved products faster. Every year, Pioneer maize researchers around the world evaluate about
130,000 new experimental hybrids. These hybrids enter a four- to five-generation testing cycle. One might think of these
experimental products as “applicants” to college. The top 10%, 13,000 from the first season of testing, make up the “freshman
college class”.
During each of the next four generations, the hybrids are tested at more locations and in a range of soil types, stresses, and
climate conditions. At every stage of testing, researchers look for high, stable yield, standability, tolerance to stresses, and other
agronomic characteristics. Only hybrids that meet Pioneer standards are advanced to the “sophomore” class. Typically, there are
about 6,000 sophomores each season, less than half of the freshman class. Each year, approximately 200 Pioneer experimental
hybrids make it to the “junior” level, and fewer than 100 hybrids make it to the “senior” level. And finally, from about 130,000
original candidates, only about 15–20 hybrids “graduate” to commercial status.
By the time a Pioneer® brand hybrid is offered for sale, it has been tested at more than 150 locations, and in more than 200 customers’
fields. This rigorous testing system helps Pioneer researchers develop leading edge, new genetics with a total package of
traits that add value for customers.
Supply management
When the decision is made to sell a new hybrid, production of that seed is undertaken by Pioneer’s Supply Management Division.
The mission of this group is to reliably provide the highest quality seed for Pioneer’s customers.
The process begins with a small number of seeds of the new product being handed off from R&D to Supply Management. From
these seeds, parent inbred lines are produced and multiplied by the division’s parent seed operations, located in the US mainland,
in Hawaii, and at locations around the globe. As the anticipated demand for the hybrid is identified, commercial volumes of seed
are grown, conditioned, and stored to fill customer needs.
The volume of seed for a given product hybrid can number into the hundreds of thousands of units (80,000 seeds constitute a
unit). However, regardless of volumes, Pioneer maintains high standards of quality – for germination rates, genetic purity, and
physical purity – and regularly monitors seed quality throughout production for all products.
In North America, there are 21 commercial corn production facilities, allowing Pioneer to grow and condition products in a
number of different environments to spread risk, while producing in the most cost-effective manner. In addition to a summer production
cycle in North America, Pioneer manages a “winter” production cycle, using its facilities in South America, to accelerate
the production of the latest products, i.e., those advanced to commercialization in the fall of one year for sale the next spring. This
winter production option also allows for recovery of seed supplies in case of a reduced summer production of a given hybrid.
The Supply Management team makes use of state-of-the-art technology and science throughout production. Research
agronomists provide the latest scientific information regarding optimum agronomic conditions to grow and harvest seed crops.
Pioneer’s sophisticated physical facilities are designed by Pioneer engineers to ensure seed quality is maintained through harvesting,
conditioning, and shipping. Despite the millions of units annually conditioned, the equipment is designed to carefully handle
every seed with minimal physical damage. A wide range of technologies – global positioning systems, bar codes, automated
sampling, and sophisticated inventory management systems – assure that Pioneer produces, ships, and tracks seed efficiently
and accurately around the world.
The annual production cycle begins with seed fields being contracted from high quality growers around a production location.
Pioneer production agronomists work closely with these growers to ensure each field meets Pioneer’s standards and is managed
to optimum production. For example, to attain the very highest seed purity, seed fields are preferred to be on rotated ground – that
is, the field had a crop other than corn during the prior growing season. Attention is also given to how well the seed crop can be
isolated from other corn crops and corn pollen. The majority of Pioneer’s seed fields are irrigated, which assures adequate moisture
is available during critical stages of the crop’s development.
Production agronomists help ensure that each field is planted with the correct ratio of individual rows of male or female inbred
parent seed and that the seed is planted at the right soil depth and population densities. Field planters are thoroughly inspected
before being filled to make sure there is no foreign grain present. Agronomists and contract seed growers work with neighboring
farmers, whose fields adjoin Pioneer’s seed ground, to guarantee that Pioneer’s strict isolation requirements can be achieved.
As the plants emerge and grow, fields are regularly checked for rogues or off-type plants to ensure that only the intended corn
plants are present. If any others are found, they are destroyed. All this is done to make sure that customers receive the superior
genetics they expect.