Method for protecting plants from stress and senescence

Abstract

The present invention relates to regulation of ureide levels for optimal plant survival during nutrient remobilization such as occurs during normal growth, dark stress and senescence. Plants can be genetically engineered or selected using a suitable gene marker to have enhanced ureide accumulation. The present invention further provides methods of protecting plants, or extending the shelf life of fresh plant produce by application of exogenous ureides.

1 . A method for protecting plants or plant parts from a stress related process comprising applying to the plant or plant part a composition comprising an amount of at least one ureide effective to decrease or delay the stress related process. 
     
     
         2 . The method according to  claim 1  wherein the composition comprises 0.001-10 mM ureide. 
     
     
         3 . The method according to  claim 2  wherein the composition comprises 0.01-10 mM ureide. 
     
     
         4 . The method according to  claim 2  wherein the composition comprises 0.1-0.5 mM ureide. 
     
     
         5 . The method according to  claim 1  wherein the stress related process is selected from the group consisting of: chlorophyll degradation, oxidative stress, senescence, premature senescence or any combination thereof. 
     
     
         6 . The method of  claim 1  wherein the plant parts are selected from fruit, vegetables cut branches and flowers. 
     
     
         7 . The method of  claim 1  wherein the plants are leafy produce. 
     
     
         8 . The method of  claim 1  wherein the plants or plant parts are detached from the ground. 
     
     
         9 . The method of  claim 1  wherein the at least one ureide is selected from uric acid, allantoin or an allantoate. 
     
     
         10 . The method of  claim 1  wherein the mode of application is selected from the group consisting of spraying; at least partially immersing the plant or plant part in the composition; and adding the composition to the plant root or plant part medium. 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . A plant having enhanced ureide production wherein the plant comprises a genetic variant of at least one enzyme in the pathway of ureide production from xanthine and wherein the genetic variant is selected using a probe specific for the at least one enzyme expression or encoding gene. 
     
     
         14 . A plant having enhanced ureide production wherein the plant comprises a genetic variant of at least one enzyme in the pathway of ureide utilization and wherein the genetic variant is selected using a probe specific for the at least one enzyme expression or encoding gene. 
     
     
         15 . A plant having enhanced ureide accumulation wherein the plant comprises a genetic variant of at least one enzyme in the pathway of ureide production from xanthine and wherein the genetic variant is selected using a probe specific for the at least one enzyme expression or encoding gene. 
     
     
         16 . A plant having enhanced ureide accumulation wherein the plant comprises a genetic variant of at least one enzyme in the pathway of ureide utilization. 
     
     
         17 . (canceled) 
     
     
         18 . (canceled) 
     
     
         19 . (canceled) 
     
     
         20 . A transgenic plant comprising at least one cell transformed with at least one polynucleotide encoding an enzyme in the pathway of ureide production from xanthine. 
     
     
         21 . The plant of  claim 20 , wherein said plant produces elevated concentration of ureide compared to a corresponding non-transgenic plant. 
     
     
         22 . A transgenic plant comprising at least one cell transformed with at least one polynucleotide encoding an enzyme in the pathway of ureide utilization. 
     
     
         23 . The plant of  claim 22 , wherein said plant accumulates elevated concentration of ureide compared to a corresponding non-transgenic plant. 
     
     
         24 . The plant of  claim 16  wherein the ureide is selected from allantoin or an allantoate. 
     
     
         25 . The plant of  claim 18  wherein the ureide is selected from allantoin or an allantoate.