Modification of plant lignin content

Abstract

DNA constructs comprising a first DNA segment that corresponds to at least a portion of a gene in the monolignol biosynthetic pathway, a spacer DNA segment, and a second DNA segment that is complementary to the first DNA segment can be used to reduce or modulate the lignin content in plants. In some embodiments, DNA constructs comprise at least a portion of a gene for 4CL, C3H, CCR, C4H or CCoAOMT. Vascular-preferred and constitutive promoters can be used to drive expression of the constructs.

1 - 8 . (canceled) 
     
     
         9 . A DNA construct comprising a promoter operably linked to a DNA segment that corresponds to at least a portion of a CAld5H gene, wherein said DNA construct is selected from the group consisting of pARB1203, pARB1205, pARB675, pARB661, pARB662 and pARB374. 
     
     
         10 . The DNA construct of  claim 9 , wherein the DNA construct is pARB1203. 
     
     
         11 . The DNA construct of  claim 9 , wherein the DNA construct is pARB1205. 
     
     
         12 . The DNA construct of  claim 9 , wherein the DNA construct is pARB675. 
     
     
         13 . The DNA construct of  claim 9 , wherein the DNA construct is pARB661. 
     
     
         14 . The DNA construct of  claim 9 , wherein the DNA construct is pARB662. 
     
     
         15 . (canceled) 
     
     
         16 . A plant cell comprising the DNA construct of  claim 9 . 
     
     
         17 . A plant comprising the plant cell of  claim 16 . 
     
     
         18 . Pulp and pulp-derived products derived from the plant of  claim 17 . 
     
     
         19 . Solid wood products derived from the plant of  claim 18 . 
     
     
         20 . The wood products of  claim 19  wherein the products are selected from the group consisting of timber, lumber and composite. 
     
     
         21 . (canceled) 
     
     
         22 . A method of altering the lignin composition in a plant, comprising integrating into said plant's genome the DNA construct of  claim 9 . 
     
     
         23 . The method according to  claim 22 , wherein said alteration in lignin composition comprises modifying the guaiacyl:syringyl lignin monomer ratio in the transformed plant. 
     
     
         24 . A method of making wood comprising integrating into a plant cell's genome the DNA construct of  claim 9 , growing said plant cell and obtaining said wood. 
     
     
         25 . Wood obtained by the method of  claim 24 . 
     
     
         26 . A method of making wood pulp comprising integrating into a plant cell's genome the DNA construct of  claim 9 . 
     
     
         27 . Wood pulp obtained by the method of  claim 26 . 
     
     
         28 . A method of making paper comprising integrating into a plant cell's genome the DNA construct of  claim 9 . 
     
     
         29 . Paper obtained by the method of  claim 28 .