The role of shikimic acid in regulation of growth, transpiration, pigmentation, photosynthetic activity and productivity of Vigna sinensis plants

The effect of shikimic acid on growth parameters, total leaf conductivity, transpiration, photosynthetic pigments, C-14 assimilation and productivity of Vigna sinensis (Fabaceae - Phaseoleae) plants was studied. Shikimic acid application led to an increase in fresh and dry weights of cowpea plants a nd enhances leaf expansion as well as the root length and plant height. Seed pretreatment with shikimic acid at Various doses induces a marked incr ease in total leaf conductivity and transpiration rate at different stages of growth. Shikimic acid at all concentrations was found to stimulate the production o f Chl.a, Chl.b, Carotenoids and C-14 fixation during leaf growth and develo pment. Furthermore, shikimic acid at various doses applied improved yield a nd yield components of cowpea plants by increasing the number of pods/plant , length of pod, number of seeds/pod, seed biomass and 100-seed weight. The protein content of yielded seeds was increased in response to shikimic aci d treatments. On the other hand, shikimic acid at all concentrations signif icantly decreased the polysaccharide content of developed cowpea seeds. In the majority of cases, the absolute values of total soluble sugars and sucr ose in cowpea seeds appeared to be nan-significantly affected in response t o seed priming with shikimic acid.