Methods and Compositions for Peronospora Resistance in Spinach

Abstract

The present disclosure provides for unique spinach plants with broad-spectrum resistance to downy mildew and their progeny. Such plants may comprise an introgressed QTL associated with the broad-spectrum resistance to downy mildew. In certain aspects, compositions, including distinct polymorphic molecular markers, and methods for producing, using, identifying, selecting, and the like of plants or germplasm with resistance to downy mildew are provided.

1 . A  Spinacia oleracea  spinach plant comprising in its genome an introgressed locus from  Spinacia tetrandra  that confers broad-spectrum resistance to  Peronospora farinosa f . sp.  Spinaciae.    
     
     
         2 . The spinach plant of  claim 1 , wherein:
 (a) the broad-spectrum resistance comprises resistance to races 7, 10, 11, 12, 13, and 14 of  Peronospora farinosa f . sp.  spinaciae  (Pfs);   (b) resistance to races 1-14 and UA4712 of  Peronospora farinosa f . sp.  spinaciae  (Pfs); or   (c) wherein the introgressed locus is defined as flanked in the  Spinacia tetrandra  genome by sequences at least 95% identical to SEQ ID NOs:1 or 2.   
     
     
         3 . (canceled) 
     
     
         4 . The spinach plant of  claim 1 , wherein said plant is defined as:
 (a) an inbred plant;   (b) a hybrid plant; or   (c) an agronomically elite plant.   
     
     
         5 .- 7 . (canceled) 
     
     
         8 . The agronomically elite spinach plant of  claim 3 , wherein a representative sample of seed comprising said locus has been deposited under Accession No. PTA-120533 or Accession No. PTA-120534. 
     
     
         9 . A seed that produces the plant of  claim 1 . 
     
     
         10 . A plant part of the plant of  claim 1 . 
     
     
         11 . The plant part of  claim 10 , wherein the plant part is selected from the group consisting of an embryo, meristem, cotyledon, pollen, leaf, anther, root, pistil, flower, cell, and stalk. 
     
     
         12 . A recombined chromosomal segment comprising an allele from  Spinacia tetrandra  conferring broad-spectrum resistance to  Peronospora farinosa f . sp.  spinaciae  and lacking all or some genetic loci that are genetically linked thereto in  Spinacia tetrandra.    
     
     
         13 . The chromosomal segment of  claim 12 , further defined as comprising at least a first genetic locus from  Spinacia oleracea.    
     
     
         14 . The chromosomal segment of  claim 12 , wherein a representative sample of seed comprising said allele from  Spinacia tetrandra  conferring broad-spectrum resistance to  Peronospora farinosa f . sp.  spinaciae  has been deposited under Accession No. PTA-120533 or Accession No. PTA-120534. 
     
     
         15 . A  Spinacia oleracea  spinach plant comprising the chromosomal segment of  claim 14 . 
     
     
         16 . A  Spinacia oleracea  spinach seed comprising the chromosomal segment of  claim 14 . 
     
     
         17 . A method of selecting a plant with broad-spectrum resistance to  Peronospora farinosa f . sp.  spinaciae  comprising selecting said plant based on the presence in the genome of the plant of at least a first genetic polymorphism in or in genetic linkage disequilibrium with a chromosomal segment from  Spinacia tetrandra  conferring said resistance, wherein the locus is flanked in the  Spinacia tetrandra  genome by loci corresponding to SEQ ID NOs:1 or 2, or sequences at least 95% identical thereto. 
     
     
         18 . The method of  claim 17 , wherein:
 (a) the plant is a  Spinacia oleracea  plant comprising in its genome at least one introgressed locus from  Spinacia tetrandra ; or   (b) the plant is a  Spinacia tetrandra  plant.   
     
     
         19 . (canceled) 
     
     
         20 . The method of  claim 17 , further comprising:
 (a) the step of confirming the presence of said broad-spectrum resistance with a phenotypic assay; or   (b) crossing said plant comprising the locus with a second plant to produce a progeny plant comprising said locus.   
     
     
         21 . (canceled) 
     
     
         22 . A method for producing an agronomically elite spinach plant that comprises in its genome at least one locus conferring broad-spectrum resistance to  Peronospora farinosa f . sp.  spinaciae  (Pfs), the method comprising:
 (i) crossing a first spinach plant with a second spinach plant, wherein the first plant comprises in its genome at least one locus from  Spinacia tetrandra  that confers broad-spectrum resistance to  Peronospora farinosa f . sp.  Spinaciae , and wherein the second plant lacks said locus; and   (ii) selecting at least a first progeny spinach plant resulting from said crossing that comprises said locus.   
     
     
         23 . The method of  claim 22 , further comprising the step of:
 (iii) crossing the progeny plant spinach plant with itself or another spinach plant to produce a progeny spinach plant of a subsequent generation.   
     
     
         24 . The method of  claim 23 , wherein steps (ii) and (iii) are repeated at least about 3 times to about 10 times. 
     
     
         25 . The method of  claim 22 , wherein:
 (a) the first plant is a  Spinacia tetrandra  plant and the second plant is a  Spinacia oleracea  plant; or   (b) selecting comprises identifying said locus in the genome of the progeny based on the detection of a genetic polymorphism as set forth in SEQ ID NOs:1 and 2 or in genetic linkage disequilibrium with said locus, wherein the locus is flanked in the  Spinacia tetrandra  genome by loci corresponding to SEQ ID NOs:1 or 2, or sequences at least 95% identical thereto.   
     
     
         26 . (canceled) 
     
     
         27 . A method of producing an agronomically elite spinach plant comprising broad-spectrum resistance to  Peronospora farinosa f . sp.  spinaciae  (Pfs), comprising introgressing into an agronomically elite  Spinacia oleracea  plant a chromosomal segment from  Spinacia tetrandra  that confers the resistance, wherein said locus is defined as located in a region of the  Spinacia tetrandra  genome flanked by loci corresponding to the  Spinacia tetrandra  allele in SEQ ID NOs:1 or 2, or sequences at least 95% identical thereto. 
     
     
         28 . The method of  claim 27 , wherein said introgressing comprises recovering essentially all of the  Spinacia oleracea  genome in said plant other than said locus by at least about 3-10 generations of backcrossing using a  Spinacia oleracea  plant as a recurrent parent. 
     
     
         29 . The method of  claim 27 , further comprising:
 (a) the step of confirming the presence of said broad-spectrum resistance by a phenotypic assay; or   (b) identifying at least a first plant comprising said locus, and crossing the plant comprising said locus to another spinach plant to produce a progeny plant comprising said locus.   
     
     
         30 . (canceled) 
     
     
         31 . A spinach plant or progeny thereof obtainable by introgressing a locus from  S. tetrandra  conferring broad-spectrum resistance to  Peronospora farinosa f . sp.  spinaciae  (Pfs) into  S. oleracea.    
     
     
         32 . The spinach plant of  claim 31 , wherein:
 (a) the broad-spectrum resistance comprises resistance to at least races 7, 10, 11, 12, 13, and 14 of  Peronospora farinosa f . sp.  spinaciae  (Pfs);   (b) the broad-spectrum resistance comprises resistance to all known races of  Peronospora farinosa f . sp.  spinaciae  (Pfs);   (c) the introgressed locus is defined as flanked by SEQ ID NOs:1 or 2 in the  Spinacia tetrandra  genome; or   (d) a representative sample of seed comprising said locus has been deposited under Accession No. PTA-120533 or Accession No. PTA-120534.   
     
     
         33 . (canceled) 
     
     
         34 . The spinach plant of  claim 31 , wherein said plant is defined as:
 (a) an inbred plant;   (b) a hybrid plant; or   (c) an agronomically elite plant.   
     
     
         35 .- 38 . (canceled) 
     
     
         39 . A seed that produces the plant of  claim 31 . 
     
     
         40 . A plant part of the plant of  claim 31 . 
     
     
         41 . The plant part of  claim 40 , wherein the plant part is selected from the group consisting of an embryo, meristem, cotyledon, pollen, leaf, anther, root, pistil, flower, cell, and stalk. 
     
     
         42 . A food product comprising the harvested leaves of the spinach plant of  claim 1 .