ABSTRACT
In plant organs, PAs are positively implicated in plant growth and differentiation as well as in stress responses. In plant tissues, the main PAs (Figure 7.1) are putrescine (Put, 1,4-diaminobutane), spermidine (Spd, N-3-aminopropyl-1,4-diaminobutane), and spermine (Spm, [bis(N3-aminopropyl)-1,4-diaminobutane]). The three PAs are present ubiquitously as polycationic compounds and are found in signicant amounts in vegetable cell types (nanomolar to micromolar concentrations) to support a wide variety of cellular functions.
