Location: Tropical Crops and Germplasm Research
2013 Annual Report
Developing a soybean variety requires about eight seasons of soybean production. The first five are needed to mate the parental stock and develop true-breeding progeny. An additional three are required to yield test the progeny in North Carolina and ‘pick the winners’ for farmer use. Normally, 8 seasons of breeding would take 8 years. However, we can shorten the process two years by growing extra soybean crops during North Carolina’s off-season (November through April) at the USDA-ARS Research Farm in Isabela, Puerto Rico. This site is frost free and is an excellent off-season environment for North Carolina breeding programs. The importance of the winter nursery is highlighted by the fact that all of the varieties released in North Carolina have been developed using the Puerto Rico winter nursery.
During the 2012-2013 season we planted our USDA winter nursery on the first week of December 2012 at Isabela, Puerto Rico. NC Soybean Producers visited the USDA station in Puerto Rico in late March to observe the operations of the USDA winter nursery first hand.
In total, the USDA soybean breeders located in North Carolina grew approximately 778 10-feet long rows of soybean under extended light conditions. These included approximately 2500 individual F1 plants and 411 bulk-harvested rows. We also grew approximately 860 rows of unlighted rows. For the unlighted rows we harvested 1 pod per plant manually, following the single seed descent method of soybean breeding. After harvest and prior to APHIS inspection, all seed were cleaned manually and any seed which were appeared diseased were discarded. After seed inspection, seed were boxed and airlifted to North Carolina for spring planting.
The following are breeding objectives in this program: incorporate new genetic diversity from exotic Asian soybean germplasm into adapted commercial varieties, increase yield, improve seed composition and drought tolerance, and adaptation to the soyfoods market.