Disease resistant potato plants

Abstract

The present invention relates to a plant, which is resistant to a pathogen of viral, bacterial, fungal or oomycete origin, wherein the plant has a reduced level, reduced activity or complete absence of DMR6 protein as compared to a plant that is not resistant to the said pathogen, in particular organisms of the Fungi or the phylum Oomycota. The invention further relates to a method for obtaining a plant, which is resistant to a pathogen of viral, bacterial, fungal or oomycete origin, comprising reducing the endogenous level or activity of DMR6 protein in the plant. In addition, the invention relates to the use of a DMR6 promotor for providing disease resistant plants.

1 : An isolated potato plant which is resistant to  Phytophthora infestans , wherein the potato plant has a reduced level or reduced activity of DMR6 protein as compared to a potato plant that is not resistant to  Phytophthora infestans , wherein said potato plant has either:
 a non-natural mutation introduced into the dmr6 gene of SEQ ID NO: 113 and said plant has a reduced level or reduced activity of the DMR6 protein of SEQ ID NO: 112, or   a non-natural mutation introduced into the dmr6 gene of SEQ ID NO: 115 and said plant has a reduced level or reduced activity of the DMR6 protein of SEQ ID NO: 114.   
     
     
         2 : The potato plant as claimed in  claim 1 , wherein the mutation in the dmr6 gene leads to an amino acid substitution in the DMR6 protein. 
     
     
         3 : The potato plant as claimed in  claim 1 , wherein the potato plant has a non-natural mutation introduced into the dmr6 gene of SEQ ID NO: 113 and said plant has a reduced level or reduced activity of the DMR6 protein of SEQ ID NO: 112. 
     
     
         4 : The potato plant as claimed in  claim 1 , wherein the potato plant has a non-natural mutation introduced into the dmr6 gene of SEQ ID NO: 115 and said plant has a reduced level or reduced activity of the DMR6 protein of SEQ ID NO: 114. 
     
     
         5 : A seed, tissue, or plant part of the potato plant according to  claim 1 , wherein the seed, tissue, or plant part comprises the mutation in the dmr6 gene of SEQ ID NO: 113 or SEQ ID NO: 115 and has a reduced level or reduced activity of the DMR6 protein of SEQ ID NO: 112 or SEQ ID NO: 114. 
     
     
         6 : A method for obtaining a potato plant which is resistant to  Phytophthora infestans , the method comprising reducing an endogenous level of the DMR6 protein of SEQ ID NO: 112 or SEQ ID NO: 114 in a potato plant by introducing a mutation into the dmr6 gene of SEQ ID NO: 113 or SEQ ID NO: 115 to produce a potato plant that is resistant to  Phytophthora infestans.    
     
     
         7 : The method of  claim 6 , wherein the method comprises reducing an endogenous level of the DMR6 protein of SEQ ID NO: 112 in a potato plant by introducing a mutation into the dmr6 gene of SEQ ID NO: 113 to produce a potato plant that is resistant to  Phytophthora infestans.    
     
     
         8 : The method of  claim 6 , wherein the method comprises reducing an endogenous level of the DMR6 protein of SEQ ID NO: 114 in a potato plant by introducing a mutation into the dmr6 gene of SEQ ID NO: 115 to produce a potato plant that is resistant to  Phytophthora infestans.    
     
     
         9 : The method of  claim 6 , wherein reducing the endogenous level of the DMR6 protein in the potato plant is achieved by reducing expression of the dmr6 gene of SEQ ID NO: 113 or SEQ 10 NO: 115. 
     
     
         10 : The method of  claim 9 , wherein reducing expression of the dmr6 gene of SEQ ID NO: 11.3 or SEQ ID NO: 115 is achieved by gene silencing or RNAi. 
     
     
         11 : The method of  claim 6 , wherein the mutation results in one or more amino acid changes that leads to a reduced enzymatic activity of the DMR6 protein of SEQ ID NO: 112 or SEQ ID NO: 114. 
     
     
         12 : The method of  claim 6 , wherein the mutation is effected by a mutagenic treatment of the potato plant. 
     
     
         13 : The method according to  claim 12 , wherein the mutagenic treatment is effected with a mutagen or with radiation. 
     
     
         14 : A potato plant produced from the method according to  claim 6 , wherein the plant comprises the mutation in the dmr6 gene of SEQ ID NO: 113 or SEQ ID NO: 115 and said potato plant has a reduced level or reduced activity of the DMR6 protein of SEQ ID NO: 112 or SEQ ID NO: 114. 
     
     
         15 : A seed, tissue, or plant part of the potato plant according to  claim 14 , wherein the seed, tissue, or plant part comprises the mutation in the dmr6 gene of SEQ ID NO: 113 or SEQ ID NO: 115 and has a reduced level or reduced activity of the DMR6 protein of SEQ ID NO: 112 or SEQ ID NO: 114.