Phenotypic and Genetic Similarity Between the Soybean Cultivars CNS, Punjab-1, and Nanking 332.

The soybean cultivars CNS and Punjab-1 are dominant and important ancestors in the genetic base of current southern United States and Indian soybean cultivars, respectively.  CNS and Punjab-1 are described as selections from a Nanking type.  The phrase ‘Nanking (aka Nanjing or Jin Da) type’ is related to a collaborative soybean evaluation project in the 1920’s between the College of Agriculture of Nanking University, the University of Nanking, and Cornell University.  Approximately 10,000 landraces were collected, named in a series as Nanking 1 - 10,000 and evaluated agronomically.  Nanking (aka Nanksoy and Jin Da) 332 is the first soybean variety released from China as a result of that screening effort.  It is not clear from the literature as to which Nanking type is the source for CNS and Punjab-1.  The objective of this research was to attempt to determine that origin.  There are many soybean accessions in the USDA soybean germplasm collection today which appear related to, or a part of, the Nanking series. The plant introductions from the USDA germplasm collection that were collected from Jiangsu province prior to 1950, and submitted by C.H. Hehm, Y.S. Tsiang, and A.K. Smith, were included with CNS, Punjab-1, and Nanking 332 in a field test to asses agronomic and seed quality data for a direct comparison.  A total of 30 cultivars were grown in a randomized complete block design (RCBD) with three replications at Sandhills, NC during 2005, 2006, 2007, and 2008.  Selection of the most similar cultivars led to a follow-up test of 10 cultivars grown in a RCBD with four replications at three locations in North Carolina during 2009 and 2010.