Clubroot resistant brassica oleracea plants

Abstract

The present invention discloses B. oleracea plants resistant to clubroot disease. In particular, the plants of the present invention comprise a monogenic dominant resistance to the disease clubroot introgressed from B. rapa. This resistance provides improved resistance to the disease as compared to previously existing resistances in B. oleracea.

1 . A  B. oleracea  plant resistant to clubroot disease, wherein the resistance to clubroot is monogenic and dominant.  
     
     
         2 . The plant according to  claim 1 , wherein said  B. oleracea  plant is rated at level 2 or less in a test for the disease having a 1-9 scale or at a level 1 or less in a test for the disease having a 0-5 scale.  
     
     
         3 . The plant according to  claim 1 , wherein said  B. oleracea  plant is rated at level 1 in a test for the disease having a 1-9 scale or at a level 0 in a test for the disease having a 0-5 scale.  
     
     
         4 . The plant according to  claim 1 , wherein said  B. oleracea  plant is broccoli, white cabbage, cauliflower, Brussels sprouts, Borecole, Savoy, or red cabbage.  
     
     
         5 . The plant according to  claim 1 , wherein said resistance is linked to a molecular marker obtainable by PCR amplification.  
     
     
         6 . The plant according to  claim 1 , wherein said resistance is linked to a molecular marker obtainable by PCR amplification using primer O20 (SEQ ID NO:1) or primer Y13 (SEQ ID NO:2).  
     
     
         7 . The plant according to  claim 5 , wherein said resistance is within 10 cM of said molecular marker.  
     
     
         8 . The plant according to  claim 5 , wherein said resistance is within 6 cM of said molecular marker.  
     
     
         9 . The plant according to  claim 1 , wherein said resistance is obtainable from a clubroot resistant  B. rapa  plant.  
     
     
         10 . The plant according to  claim 1 , wherein said resistance is obtainable from Chinese cabbage F1 hybrid Parkin.  
     
     
         11 . A  B. oleracea  plant comprising a locus conferring resistance to clubroot disease, wherein said resistance is monogenic and dominant.  
     
     
         12 - 16 . (canceled)  
     
     
         17 . The plant according to  claim 1 , wherein said  B. oleracea  plant is homozygous for said resistance.  
     
     
         18 . The plant according to  claim 1 , wherein said  B. oleracea  plant is heterozygous for said resistance.  
     
     
         19 . The plant according to  claim 1 , wherein said  B. oleracea  plant is an inbred or a dihaploid.  
     
     
         20 . The plant according to  claim 1 , wherein said  B. oleracea  plant is a hybrid.  
     
     
         21 . The plant according to  claim 19 , wherein said  B. oleracea  plant is cytoplasmic male sterile.  
     
     
         22 . Seed of a plant according to  claim 1 .  
     
     
         23 . Fruit or part of a plant according to  claim 1 .  
     
     
         24 . Part of a plant according to  claim 1 , wherein said part is pollen, ovule or embryo.  
     
     
         25 - 26 . (canceled)  
     
     
         27 . A method for producing a  B. oleracea  plant comprising a monogenic and dominant resistance to clubroot comprising the steps of: 
 a) obtaining a  B. rapa  plant resistant to clubroot;    b) crossing said  B. rapa  plant with a  B. oleracea  plant,    c) rescuing embryos resulting from the cross of step b);    d) regenerating a plant from a embryo of step c);    e) selecting a plant of step d) that is resistant to clubroot;    f) back-crossing a plant resulting from step e) with a  B. oleracea  plant.    
     
     
         28 . The method according to  claim 27 , further comprising introgressing the resistance into an elite  B. oleracea  inbred.  
     
     
         29 . The method according to  claim 28 , further comprising crossing said inbred to another  B. oleracea  inbred to produce a hybrid.  
     
     
         30 . A  B. oleracea  plant obtainable by the method of  claim 27 .  
     
     
         31 . A method for transferring a monogenic and dominant resistance to clubroot to a  B. oleracea  plant susceptible or less resistant to the disease comprising the steps of: 
 a) obtaining a  B. oleracea  plant comprising a monogenic and dominant resistance to clubroot;    b) crossing said  B. oleracea  plant of step a) with a  B. oleracea  plant susceptible or less resistant to clubroot;    c) selecting a plant from the cross of step b) that is resistant to clubroot.    
     
     
         32 . The method according to  claim 31 , further comprising backcrossing said resistance into said  B. oleracea  plant susceptible or less resistant to clubroot.  
     
     
         33 . A DNA fragment amplified from a  Brassica  genome, wherein said DNA fragment is approximately 400 bp long and comprises SEQ ID NO:1 or wherein said DNA fragment is approximately 640 bp long and comprises SEQ ID NO:2.  
     
     
         34 . (canceled)  
     
     
         35 . The DNA fragment according to  claim 33 , wherein said DNA fragment is indicative of the presence of a dominant and monogenic resistance to clubroot in a  Brassica  plant.  
     
     
         36 - 40 . (canceled)  
     
     
         41 . A kit for detecting a monogenic and dominant resistance to clubroot in a  B. oleracea  plant comprising an oligonucleotide of set forth in SEQ ID NO:1 or SEQ ID NO:2.  
     
     
         42 . A method for transferring a monogenic and dominant resistance to clubroot to a  B. oleracea  plant susceptible or less resistant to the disease comprising the steps of: 
 a) obtaining a  B. oleracea  plant comprising a monogenic and dominant resistance to clubroot;    b) crossing said  B. oleracea  plant of step a) with a  B. oleracea  plant susceptible or less resistant to clubroot;    c) selecting a plant comprising a DNA fragment obtainable by PCR amplification using primer O20 (SEQ ID NO:1) or primer Y13 (SEQ ID NO:2);    wherein said plant of step c) is resistant to clubroot.    
     
     
         43 . The method according to  claim 42 , further comprising backcrossing said resistance into said  B. oleracea  plant susceptible or less resistant to clubroot.  
     
     
         44 - 45 . (canceled)  
     
     
         46 . Seed of a plant according to  claim 11 .  
     
     
         47 . Fruit or part of a plant according to  claim 11 .  
     
     
         48 . The plant according to  claim 11 , further comprising a nucleic acid sequence, which can be amplified by PCR using primer O20 (SEQ ID NO:1) or primer Y13 (SEQ ID NO:2).  
     
     
         49 . The plant according to  claim 48 , wherein a DNA fragment of approximately 400 bp is amplified using primer O20 (SEQ ID NO:1).  
     
     
         50 . The plant according to  claim 48 , wherein a DNA fragment of approximately 640 bp is amplified using primer Y13 (SEQ ID NO:2).  
     
     
         51 . Seed of a plant according to  claim 48 .  
     
     
         52 . Fruit or part of a plant according to  claim 48.