They are simply the indicators of extent of water stress.Their accumulation is plant during water stress indicates the extent to which the plant is exposed to water stress. Many studies have indicated the folk at application of low biuret urea accelerated the accumulation of these polyamines and triggered the much higher induction of flowering following resumption of optimum growing conditions

1. The β-aminobutyric acid (a 4-carbon non-protein amino acid) treatments to some plants (such as Arabidopsis, wheat, potato, maize etc.) increased water or drought stress tolerance. Currently, the β-aminobutyric acid is identified as an endogenous plant signaling molecule and participate in various morphological, physio-biochemical processes under abiotic stresses. Please seed attached file number 1 for detail information.

2. Several reports are available and have shown that spermidine (a polyamine) is associated in the regulation of plant response to abiotic stresses such as drought or osmotic stress, salinity, heat and chilling by binding with membrane phospholipids, osmotic adjustment, scavenging of free radicals and maintaining a cation-anion equilibrium. Many biochemical and physiological effects are provoked by exogenous application of spermidine under stress conditions. They maintained antioxidant enzyme activities (superoxide dismutase, peroxidase, catalase etc.) in plants which are able to moderate radical scavenging system to reduce oxidative stress. Please check this attached research paper (number 2) for evidence in detail.

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