Soybean intercropping with other crops usually causes poor yield, mainly by light reduction . Sometimes, a continuous rainfall during the growing season in the area of monsoon is a major factor for yield reduction in soybean by insufficient sunlight as well as shading by intercropping. Recently our laboratory has collected over 1500 lines as germplasm for Korean native soybean lines and has conducted tests for evaluation of various agronomic characters.
Kwon, Shin Han and Won, Jong Lak
"Research notes: Preliminary studies for screening techniques on shade tolerance
Soybean Genetics Newsletter: Vol. 6
, Article 34.
Available at: http://lib.dr.iastate.edu/soybeangenetics/vol6/iss1/34