RRSB is genetically engineered to be tolerant to the herbicide glyphosate (Round Up® “Roundup”). Since the deregulation in 2005, RRSB have been widely commercialized in the United States. In the 2009-10 crop year, RRSB varieties accounted for about 95 percent of planted sugar beet crop.
About Sugar Beets
U.S. farmers produce sugar crops that meet about 90% of domestic sugar demand, and the remaining 10% is imported. About half of the domestically produced sugar is extracted from sugar beets, with the other half extracted from sugarcane; the United States being one of the few countries that produces both of these sugar crops. Beets are grown in cooler northern states while cane is grown in warmer southern states. Each year U.S. farmers grow sugar beets on more than 1 million acres in the states of MI, MN, ND, MT, NE, WY, CO, ID, WA, and CA. Sugar beet is a relatively modern field crop, having been developed in Europe in the late 1800's. Sugar beets were derived directly from fodder beets which are commonly grown for livestock feed. Fodder beets, as well as the vegetable crops table beet and Swiss chard, are all members of the same species and are capable of interbreeding.
Sugar Beet Production
Beets are biennials, meaning that it takes two years to complete the full life cycle. During the first year, beets grow as a rosette and develop a swollen storage root. In the second year, the energy contained in the storage root is utilized to produce a seed stalk, completing the life cycle. Exposure to a period of cool temperatures and long nights, referred to as vernalization, triggers the transition from the vegetative to reproductive phases of growth. Carrots and onions are other examples of crops with similar biennial life cycles.
While sugar beets, table beets and chard are all naturally biennial, the agricultural commodities are produced from plants grown as summer annuals. That is, they are harvested during the first year of growth prior to vernalization and flowering. In contrast, beet seed production requires the completion of the natural biennial life cycle. Since the agricultural commodities of beet are all vegetative, farmers are not able to produce their own seed for subsequent crops.
Beet seed production is a highly specialized operation primarily due to the biennial nature of the plant. The most essential climatic requirement is mild winters, cool enough to induce vernalization, yet not so cold to cause freezing damage. In the United States, nearly all of the sugar beet seed is produced in the Willamette Valley of Oregon, while most of the table beet seed is produced in Western Washington. These regions have mild winters and dry summers that are perfect for growing the highest quality seed of biennial crops.
The entire U.S. sugar beet crop is planted with hybrid seed which can be produced by one of two methods: the direct-seeded method and the steckling (transplant) method. Stecklings are carrot-sized roots that have been vernalized. In the direct-seeded method, the male and female parents are planted in strips in the same field and left in place until the seed is harvested from the female plants the following year. When the steckling method is used, the seed of the parental lines is planted in a steckling nursery where fall growth and vernalization occur. These relatively small roots are then transplanted to seed production fields in January and February. While the steckling method of seed production is more expensive, it provides seed companies with an additional opportunity for inventory management. In either case, the male parent is destroyed after pollination to ensure that only hybrid seed is harvested.