Plant growth regulator compositions and methods of using same

Abstract

Methods of improving plant growth involve applying a first growth composition to a plant or part thereof during a first growth stage. The first growth composition includes a first active component combination comprised of auxin, gibberellin and cytokinin. The amount of cytokinin is less than the amount of auxin and gibberellin. The method also involves adjusting the amount of auxin, the amount of gibberellin, and/or the amount of cytokinin after the first growth stage, and applying a second growth composition to the plant or part thereof during a second growth stage. The second growth composition can include a second active component combination, different than the first, that includes a second amount of auxin, a second amount of gibberellin, and a second amount of cytokinin. In some examples, the method can also involve growing the plant to maturity, thereby improving growth of the plant.

What is claimed is: 
     
         1 . A method of improving plant growth, the method comprising:
 applying a first growth composition to a plant or part thereof during a first growth stage, the first growth composition comprising a first active component combination comprised of: an amount of auxin, an amount of gibberellic acid, and an amount of cytokinin,
 wherein the amount of cytokinin is less than the amount of auxin and gibberellic acid; 
   adjusting the amount of auxin, the amount of gibberellic acid, and/or the amount of cytokinin after the first growth stage;   applying a second growth composition to the plant or part thereof during a second growth stage, the second growth composition comprising a second active component combination, different than the first active component combination, and comprised of: a second amount of auxin, a second amount of gibberellic acid, and a second amount of cytokinin; and   growing the plant to maturity, thereby improving growth of the plant.   
     
     
         2 . The method of  claim 1 , wherein the amount of cytokinin in the first growth composition is about 0 to about 20 wt % by weight of the first active component combination. 
     
     
         3 . The method of  claim 1 , wherein the amount of auxin in the first growth composition is about 20 to about 67 wt % by weight of the first active component combination. 
     
     
         4 . The method of  claim 1 , wherein the amount of gibberellic acid in the first growth composition is about 20 to about 67 wt % by weight of the first active component combination. 
     
     
         5 . The method of  claim 1 , wherein the plant or part thereof comprises a seed, a stem, a leaf, roots, and/or combinations thereof. 
     
     
         6 . The method of  claim 1 , wherein applying the first growth composition comprises seed-applied or in-furrow application of the first growth composition. 
     
     
         7 . The method of  claim 1 , wherein applying the second growth composition comprises foliar application of the second growth composition. 
     
     
         8 . The method of  claim 1 , wherein the second amount of cytokinin in the second growth composition is about 45 to about 65 wt % by weight of the second active component composition. 
     
     
         9 . The method of  claim 1 , wherein the second amount of auxin in the second growth composition is about 15 to about 45 wt % by weight of the second active component composition. 
     
     
         10 . The method of  claim 1 , wherein the second amount of gibberellic acid in the second growth composition is about 10 to about 30 wt % by weight of the second active component composition. 
     
     
         11 . The method of  claim 1 , wherein the first growth stage comprises a VE growth stage. 
     
     
         12 . The method of  claim 1 , wherein the second growth stage comprises a V4 growth stage. 
     
     
         13 . The method of  claim 1 , wherein the second growth stage spans a V1 and V4 growth stage. 
     
     
         14 . The method of  claim 1 , wherein adjusting comprises increasing the amount of cytokinin at a V1 growth stage relative to the amount of auxin and gibberellic acid. 
     
     
         15 . The method of  claim 1 , wherein adjusting comprises increasing the amount of cytokinin two or more times before the plant reaches a V4 growth stage. 
     
     
         16 . The method of  claim 1 , wherein the first and second growth compositions further comprise one or more adjuvants and excipients. 
     
     
         17 . The method of  claim 1 , wherein the plant comprises a corn plant. 
     
     
         18 . The method of  claim 1 , wherein improving growth of the plant comprises increasing plant size relative to a control plant that was not treated with the first or second growth composition. 
     
     
         19 . A method of improving plant growth, the method comprising:
 applying a growth composition to a plant or part thereof, the growth composition comprising an active component combination comprised of: an amount of auxin, an amount of gibberellin, and an amount of cytokinin,
 wherein the amount of cytokinin is less than the amount of auxin and gibberellin; and 
   growing the plant to maturity, thereby improving growth of the plant.   
     
     
         20 . The method of  claim 19 , wherein the amount of cytokinin is about 0 to about 20 wt % by weight of the active component combination, the amount of auxin is about 20 to about 67 wt % by weight of the active component combination, and the amount of gibberellin is about 20 to about 67 wt % by weight of the active component combination.