A New Black Seed Coat Soybean Variety, “Socheong” with Small Seed Size, Green Cotyledon and Lodging Tolerance

Abstract

A new black seed coat soybean variety, “Socheong” was developed at the Yeongnam Agricultural Research Institute (YARI) in 2006. The goal to breed the black seed coat soybean is to develop the cultivar with high yield, lodging tolerance, resistant to disease such as soybean mosaic virus (SMV), and bacterial pustule and seed size. Socheong was selected from the cross between Milyang 78, which was late maturing, susceptible to lodging and SMV and with large seed size and green cotyledon, and Peking which was tolerant to lodging and with small seed size. The preliminary, advanced and regional yield trials for evaluation and selection of this variety were carried out from 2002 to 2006. It has determinate growth habit, white flower, brown pubescence, brown pod color, black seed coat, green cotyledon, elongated flattened seed shape, oval leaf shape and small seed size (15.7 grams per 100 seeds), and it was 3 days later in maturity than the check cultivar Cheongjakong. Socheong was higher, in the seed quality of sucrose and total sugar contents (6.8 and 8.2%) and isoflavone contents (1,754 ㎍/g) than the check cultivar. Futhermore, it has good characteristics for mechanical harvest, such as lodging tolerance, pod shattering and stem diameter. It also has been identified to have resistance to soybean mosaic virus symptom which was the troublesome soybean diseases. The average yield of Socheong was 2.21 ton per hectare in the regional yield trials carried out in four locations of Korea among seven locations from 2004 to 2006, which was 5 percent lower than the check cultivar Cheongjakong.