Compositions and methods for controlling head blight disease

Abstract

Compositions comprising microbiological strains and cultures and methods of use thereof are provided herein. Certain strains, cultures, and compositions thereof are useful for the control of head blight disease, for example, of various crop plants. Biological control compositions, and methods of use thereof to prevent, inhibit or treat the development of plant pathogens or disease and for preserving plant yield, are also provided.

1 . A microbial strain, wherein the microbial strain is a  Variovorax  sp. strain, and wherein said microbial strain has suppressive activity against head blight disease. 
     
     
         2 . The microbial strain according to  claim 1 , wherein said microbial strain is  Variovorax  sp. strain SGI-014-G01 (deposited as NRRL B-50469) or a pesticidally active variants thereof. 
     
     
         3 . The microbial strain according to  claim 2 , wherein said microbial strain comprises a DNA sequence exhibiting at least 95% sequence identity to SEQ ID NO:12. 
     
     
         4 - 5 . (canceled) 
     
     
         6 . A composition comprising the microbial strain of  claim 1  or a culture thereof, and an agriculturally effective amount of a compound or composition selected from the group consisting of an acaricide, a bactericide, a fungicide, an insecticide, a microbicide, a nematicide, a pesticide, and a fertilizer. 
     
     
         7 . A composition comprising the microbial strain of  claim 1  or a culture thereof, and a carrier. 
     
     
         8 . A composition according to  claim 7 , wherein said carrier is an agriculturally acceptable carrier. 
     
     
         9 . A composition according to  claim 7 , wherein said carrier is a plant seed. 
     
     
         10 . A composition according to  claim 7 , wherein said composition is prepared as a formulation selected from the group consisting of an emulsion, a colloid, a dust, a granule, a pellet, a powder, a spray, an emulsion, and a solution. 
     
     
         11 . A composition according to  claim 7 , wherein said composition is a seed coating formulation. 
     
     
         12 . A seed having a coating comprising a composition according to  claim 7 . 
     
     
         13 . A method for preventing, inhibiting or treating the development of a plant pathogen, wherein said method comprises growing the microbial strain of  claim 1  or a culture thereof in a growth medium or soil of a host plant prior to or concurrent with host plant growth in said growth medium or soil. 
     
     
         14 . A method according to  claim 13 , wherein said plant pathogen causes head blight disease. 
     
     
         15 . A method according to  claim 14 , wherein said plant pathogen is  Fusarium graminearum.    
     
     
         16 . A method for preventing, inhibiting or treating the development of head blight disease of a plant, wherein said method comprises applying to the plant, or to the plant's surroundings, an effective amount of the microbial strain of  claim 1  or a culture thereof. 
     
     
         17 . A method according to  claim 16 , wherein said microbial strain or culture thereof is applied to soil, a seed, a root, a flower, a leaf, a portion of the plant, or the whole plant. 
     
     
         18 . (canceled) 
     
     
         19 . A method according to  claim 16 , wherein said plant is a wheat plant, a corn plant, a barley plant, or an oat plant and/or wherein said plant is susceptible to  Fusarium graminearum.    
     
     
         20 . A method according to  claim 16 , wherein said microbial strain or culture thereof is established as an endophyte on said plant. 
     
     
         21 . A non-naturally occurring plant that is a plant artificially infected with the microbial strain of  claim 1  or a culture thereof. 
     
     
         22 . Seed, reproductive tissue, vegetative tissue, plant parts, or progeny of a non-naturally occurring plant of  claim 21 . 
     
     
         23 . A method for preparing an agricultural composition, wherein said method comprises inoculating the microbial strain of  claim 1  or a culture thereof into or onto a substratum and allowing said microbial strain or culture thereof to grow at a temperature of 1-37° C. until obtaining a number of cells or spores of at least 10 2 -10 3  per milliliter or per gram.