Barley plants having increased resistance to imidazolinone herbicides

Abstract

The present invention is directed to barley plants having increased resistance to an imidazolinone herbicide. The present invention also includes seeds produced by these barley plants and methods of controlling weeds in the vicinity of these barley plants.

1 . A method of identifying a plant comprising a recombinant or mutagenized Acetohydroxyacid synthase (AHAS) nucleic acid, wherein the AHAS nucleic acid encodes an IMI polypeptide comprising a Domain A, Domain B, Domain C, Domain D, and Domain E, wherein the Domain E comprises SEQ ID NO:11, wherein serine at amino acid residue position 3 of SEQ ID NO:11 is substituted with asparagine, said method comprising:
 (a) providing biological material from a plant;   (b) performing PCR or hybridization testing of an AHAS gene in said biological material to determine if the biological material comprises the AHAS nucleic acid encoding the IMI polypeptide; and   (c) identifying, based on the results of step (b), that the plant of step (a) comprises the AHAS nucleic acid encoding the IMI polypeptide.   
     
     
         2 . A barley plant or a progeny barley plant thereof comprising a recombinant or mutagenized AHAS nucleic acid, wherein the AHAS nucleic acid encodes an IMI polypeptide comprising a Domain A, Domain B, Domain C, Domain D, and Domain E;
 wherein the Domain E comprises SEQ ID NO:11, wherein serine at amino acid residue position 3 of SEQ ID NO:11 is substituted with asparagine; and   wherein the AHAS nucleic acid confers upon a plant an increased tolerance to an imidazolinone herbicide as compared to a wild type variety of the plant.   
     
     
         3 . The plant of  claim 2 , wherein the polynucleotide sequence comprises the nucleic acid sequence set forth in SEQ ID NO:1. 
     
     
         4 . The plant of  claim 2 , wherein said polynucleotide sequence encodes a polypeptide comprising the amino acid sequence set forth in SEQ ID NO:2. 
     
     
         5 . The plant of  claim 2 , wherein the plant is transgenic. 
     
     
         6 . The plant of  claim 2 , wherein the plant is non-transgenic. 
     
     
         7 . The plant of  claim 2 , wherein the imidazolinone herbicide comprises at least one of: imazethapyr, imazapic, imazamox, imazaquin, imazethabenz, imazapyr, a mixture of imazapyr and imazamox, or a combination thereof. 
     
     
         8 . The plant of  claim 2 , wherein the imidazolinone herbicide comprises imazethapyr. 
     
     
         9 . The plant of  claim 2 , wherein the imidazolinone herbicide comprises imazamox. 
     
     
         10 . A plant part of the plant of  claim 2 , comprising the AHAS nucleic acid. 
     
     
         11 . A plant cell of the plant of  claim 2 , comprising the AHAS nucleic acid. 
     
     
         12 . A seed produced by the plant of  claim 2 , comprising the AHAS nucleic acid. 
     
     
         13 . The seed of  claim 12 , wherein the seed is true breeding for an increased resistance to an imidazolinone herbicide as compared to a wild type variety of the barley plant seed. 
     
     
         14 . The seed of  claim 12 , wherein the seed is treated with imidazolinone herbicide. 
     
     
         15 . A method of controlling weeds within the vicinity of a barley plant, comprising:
 (a) growing, in a field, a barley plant of  claim 2 ; and   (b) contacting said plant and weeds in the field with an effective amount of an imidazolinone herbicide to which the plant is tolerant, thereby controlling the weeds.   
     
     
         16 . The method of  claim 15 , wherein the imidazolinone herbicide comprises at least one of: imazethapyr, imazapic, imazamox, imazaquin, imazethabenz, imazapyr, a mixture of imazapyr and imazamox, or a combination thereof. 
     
     
         17 . The method of  claim 16 , wherein the imidazolinone herbicide comprises imazethapyr. 
     
     
         18 . The method of  claim 16 , wherein the imidazolinone herbicide comprises imazamox. 
     
     
         19 . A method for treating a seed comprising:
 (a) providing the seed of  claim 12 ; and   (b) treating said seed with an herbicidal composition comprising an imidazolinone herbicide.