Advances in conventional soybean breeding techniques E. E. Large, E. Beche, D. Mutoni and A. Scaboo, University of Missouri, USA

Modern plant breeding is the creative utilization and balance of available tools and techniques to develop the most beneficial crops for human beings (Bernardo, 2002). The primary strategy for improving crops is the selection of one genotype over another and farmers used this technique over the past several millennia. With enough time even the relatively low outcrossing rates of self-pollinating species such as domesticated soybeans (Glycine max L. Merrill) and wild soybeans (G. soja), <3% and 13%, respectively (Fujita et al., 1997) are enough to generate useful recombination events in the absence of manual cross-pollination. Early plant breeders selected plants using mass selection without modern approaches such as replicate plots or progeny testing and slowly increased genetic gain. The resultant crop improvements were essential to the development of centralized agrarian civilizations around the world. Modern plant breeding still uses the

same approach as ancient farmers but provides more options and more efficient means to identify lines with increased breeding value, thereby improving selection efficiency and rapidly achieving genetic gain (Bernardo, 2002).