EVALUATION AND GENETIC ANALYSIS OF TWO SOYBEAN [Glycine max (L.) Merr.] RECOMBINANT INBRED LINE POPULATIONS SEGREGATING FOR RESISTANCE TO ROOT KNOT NEMATODE (Meloidogyne incognita)

One of the most economically important pathogens of US soybeans is the Southern Root Knot Nematode [(Meloidogyne incognita) (Kofoid and White) Chitwood] (Mi). Evaluation and identification of resistance is highly important to the plant breeding program at SIUC. The main objective of this study was to screen within the greenhouse two F5:7 recombinant inbred line (RIL) (n=96) from crosses between LS90-1920 or LS97-1610 (resistant parents) with `Spencer\u27 (susceptible parent) to identify sources of resistance for Mi. Additionally, the RILs were evaluated in two locations in southern Illinois (Harrisburg and Dowell) in 2011 for several agronomic characteristics including yield performance. The phenotypic data collected from field and greenhouse experiments was used to select for superior lines within the two populations. The screening data was also used to identify single nucleotide polymorphism (SNP) markers associated with Mi resistance. Initial screening of the 5,361 SNP markers indicated four SNP markers (ss247062763, ss247064854, ss247077423 and ss247067293) highly associated with resistance to Mi. The results will help accelerating selection practices, and have provided high yielding resistant lines for the creation of resistant commercial varieties