Methods of Protecting Plants from Pathogenic Fungi and Nematodes

Abstract

Methods for protecting a plant from a pathogen, particularly a pathogenic fungus or nematode, are provided. A method for enhancing pathogen resistance in a plant using the nucleotide sequences disclosed herein is further provided. The method comprises introducing into a plant an expression cassette comprising a promoter operably linked to a nucleotide sequence that encodes an antipathogenic polypeptide of the invention. Transformed plants, plant cells, seeds, and microorganisms comprising a nucleotide sequence that encodes an antipathogenic polypeptide of the embodiments, or variant or fragment thereof, are also disclosed.

1 . A transgenic plant having stably incorporated into its genome a polynucleotide sequence encoding a polypeptide that confers resistance to at least one plant pathogenic nematode, wherein said polynucleotide sequence is selected from the group consisting of: 
 a) a polynucleotide sequence encoding a polypeptide having at least 95% sequence identity to SEQ ID NO: 4;    b) a polynucleotide sequence encoding a polypeptide having at least 95% sequence identity to SEQ ID NO: 5; and    c) a polynucleotide sequence having at least 95% identity to SEQ ID NO: 6;    wherein said plant has improved resistance to at least one plant pathogenic fungus, as compared to a control plant.    
     
     
         2 . The plant according to  claim 1 , wherein said plant is a monocot.  
     
     
         3 . The plant according to  claim 1 , wherein said plant is a dicot.  
     
     
         4 . Transformed seed of the plant according to  claim 1 , wherein the seed comprise the polynucleotide.  
     
     
         5 . The plant according to  claim 1 , wherein said polynucleotide is operably linked to a promoter that drives expression in a cell of said plant, wherein said promoter is selected from the group consisting of: 
 a) a constitutive promoter;    b) a tissue-specific promoter; and    c) an inducible promoter.    
     
     
         6 . The plant according to  claim 1 , wherein the polypeptide further comprises a heterologous signal sequence.  
     
     
         7 . The plant according to  claim 6 , wherein the signal sequence is a secretion signal sequence.  
     
     
         8 . The plant according to  claim 6 , wherein the signal sequence is an organelle signal sequence.  
     
     
         9 . The plant according to  claim 8 , wherein the signal sequence is a plastid signal sequence.  
     
     
         10 . The plant according to  claim 1 , wherein said polypeptide is SEQ ID NO: 4.  
     
     
         11 . The plant according to  claim 1 , wherein said polypeptide is SEQ ID NO: 5.  
     
     
         12 . The plant according to  claim 1 , wherein said polynucleotide is SEQ ID NO: 6.  
     
     
         13 . The plant according to  claim 1 , wherein said pathogenic fungus is selected from the group consisting of: 
 (a)  Fusarium oxysporum ; and    (b)  Verticillium dahliae.      
     
     
         14 . A method for enhancing resistance of a plant to at least one plant pathogenic fungus, said method comprising: 
 (a) stably transforming a plant cell with at least one expression cassette comprising a polynucleotide sequence operably linked to a promoter that drives expression in a cell of said plant, wherein said polynucleotide sequence encodes a polypeptide that confers resistance to at least one plant pathogenic fungus, and wherein said polynucleotide sequence is selected from the group consisting of: 
 i. a polynucleotide sequence encoding a polypeptide having at least 95% sequence identity to SEQ ID NO: 4;  
 ii. a polynucleotide sequence encoding a polypeptide having at least 95% sequence identity to SEQ ID NO: 5; and  
 iii. a polynucleotide sequence having at least 95% identity to SEQ ID NO: 6; and  
   (b) regenerating a transformed plant from said plant cell, wherein the plant has enhanced resistance to said pathogenic fungus as compared to a plant that does not comprise said expression cassette.    
     
     
         15 . The method of  claim 14 , wherein said pathogenic fungus is selected from the group consisting of: 
 (a)  Fusarium oxysporum ; and    (b)  Verticillium dahliae.      
     
     
         16 . The method of  claim 14 , wherein said polynucleotide sequence encodes the polypeptide set forth in SEQ ID NO: 4.  
     
     
         17 . The method of  claim 14 , wherein said polynucleotide sequence encodes the polypeptide set forth in SEQ ID NO: 5.  
     
     
         18 . The method of  claim 14 , wherein said polynucleotide sequence is SEQ ID NO:6.  
     
     
         19 . The method of  claim 14 , wherein said promoter is selected from the group consisting of: 
 a) a constitutive promoter;    b) a tissue-specific promoter; and    c) an inducible promoter.    
     
     
         20 . The method of  claim 14 , wherein the polypeptide further comprises a heterologous signal sequence.  
     
     
         21 . The method of  claim 20 , wherein the signal sequence is a secretion signal sequence.  
     
     
         22 . The method of  claim 20 , wherein the signal sequence is an organelle signal sequence.  
     
     
         23 . The method of  claim 22 , wherein the signal sequence is a plastid signal sequence.