Cytoplasmic male sterility system production canola hybrids

Abstract

Our invention comprises a gene restorer line of Brassica napus which contains a Raphanus sativus restorer gene but is essentially free of Raphanus sativus genes which produce high glucosinolate. In particular, we provide a gene restorer line, and progeny derived therefrom, seed of which is low in glucosinolates. The Brassica napus restorer lines are free of glucosinolate-producing genes having a characteristic RFLP signature. The method of producing such lines which comprises crossing Brassica napus restorer lines and hybrids with desired Brassica napus germplasm and selecting progeny having a characteristic RFLP signature is also encompassed by the present invention.

We claim:  
     
         1 . A method of producing an improved restorer line of Brassica for use in a cytoplasmic male sterility system, said method including the steps of: 
 A) forming a plant population from a gene restorer line of  Brassica napus  which contains a  Raphanus sativus  restorer gene and  Raphanus sativus  glucosinolate genes;    B) breeding with the progeny of said plant population;    C) testing the progeny for fertility indicating the  Raphanus sativus  restorer gene is present and for levels of glucosinolate wherein the presence and absence of  Raphanus sativus  high glucosinolate production is shown; and    D) selecting progeny which are positive for presence of said restorer gene and negative for the  Raphanus sativus  glucosinolate genes.    
     
     
         2 . A method of forming  Brassica napus  hybrid seed and progeny thereof from a cytoplasmic male sterility system which includes a restorer line containing  Raphanus sativus  restorer gene, the method includes the steps of: 
 A) providing a homozygous improved restorer line produced according to claim one;    B) using said restorer line in a hybrid production field as the pollinator;    C) using cytoplasmic male sterile plants in a hybrid production field as the hybrid seed producing plant; and    D) harvesting the hybrid seed from the male sterile plant.    
     
     
         3 . A method according to  claim 2  further including the steps of: 
 A) planting the hybrid seed from the male sterile plant and growing plant therefrom.  
 
     
     
         4 . An improved  Brassica napus  plant having low glucosinolate seeds containing  Raphanus sativus  gene material that is capable of restoring fertility to the ogura cytoplasmic male sterile plants, the improvement comprising an improved  Brassica napus  plant evidencing deficient glucosinolate production from  Raphanus sativus  which produced low glucosinolate seeds.  
     
     
         5 . A  Brassica napus  plant containing  Raphanus sativus  restorer gene unlinked from  Raphanus sativus  glucosinolate genes adapted to restore fertility to ogura cytoplasmic male sterile.  
     
     
         6 . A method of producing an improved restorer line according to  claim 1  wherein step C is performed using molecular markers associated with the genetic fingerprinting.  
     
     
         7 . A method according to  claim 6  wherein the fingerprinting is done by molecular markers.  
     
     
         8 . A method according to  claim 6  wherein the molecular markers are mapping to similar regions as those in the group consisting of, WG3F7, TG1H12, OPC2, WG4D10, WG6F3.