Methods and compositions for selecting soybean plants resistant to Phytophthora root rot
The present invention relates to the field of plant breeding and disease resistance. More specifically, the invention includes a method for breeding soybean plants containing quantitative trail loci (QTL) for resistance the Phytophthora root rot (PRR) caused by Phytophthora sojae . The invention further includes the use of molecular markers in the introgression of PRR resistance QTL into soybean plants.
1. A method of introgressing at least one PRR resistance QTL into a soybean plant comprising:
a) crossing at least one Phytophthora Root Rot (PRR) resistant soybean plant with at least one second soybean plant to form a population;
b) screening said population with at least one nucleic acid marker to detect a polymorphism genetically linked to PRR resistance; and
c) selecting from said population one or more soybean plants comprising a haplotype associated with a PRR resistance QTL (quantitative trait locus), wherein the PRR resistance haplotype comprises the polymorphism, and wherein the PRR resistance QTL comprises SEQ ID NO: 8.
2. The method according to claim 1 , wherein at least 51% or at least 75% of the selected soybean plants exhibit a resistant reaction to PRR.
3. The method of claim 1 , further comprising the step (d) of assaying said selected soybean plant for resistance to a PRR inducing pathogen.
4. The method of claim 1 , wherein said genotype is determined by an assay which is selected from the group consisting of single base extension (SBE), allele-specific primer extension sequencing (ASPE), DNA sequencing, RNA sequencing, microarray-based analyses, universal PCR, allele specific extension, hybridization, mass spectrometry, ligation, extension-ligation, and Flap Endonuclease-mediated assays.
5. The method of claim 1 , further comprising the step of crossing the soybean plant selected in step (c) to another soybean plant.
6. The method of claim 1 , further comprising the step of obtaining seed from the soybean plant selected in step (c).
7. A method of introgressing an allele into a soybean plant comprising:
a crossing a PRR resistant soybean plant with a second soybean plant to form a population of soybean plants;
b genotyping at least one soybean plant in the population with a soybean genomic nucleic acid marker to detect a polymorphism genetically linked to Phytophthora Root Rot (PRR) resistance; and
c selecting from said population one or more soybean plants comprising a haplotype associated with a PRR resistance allele, wherein said PRR resistance haplotype comprises the polymorphism and SEQ ID NO: 8.
8. The method according to claim 7 , wherein said selected one or more soybean plants exhibit increased grain yield in the presence of a PRR inducing pathogen as compared to soybean plants lacking the PRR resistance allele.
9. The method according to claim 8 , wherein said selected one or more soybean plants exhibit an increased grain yield of at least 0.5 Bu/A, at least 1.0 Bu/A or at least 1.5 Bu/A in the presence of a PRR inducing pathogen as compared to soybean plants lacking the PRR resistance allele.