Marine bioactive substances (IPA extract) improve foliar ion uptake and water stress tolerance in potted Vitis vinifera plants.

摘要

The effects of marine bioactive substances (IPA extract) on K+ and Ca2+ fluxes, and water stress tolerance in potted V. vinifera (cv. Sangiovese) plantlets were studied. Different foliar treatments were compared: a control treatment (distilled water), a pure fertilizer treatment (9-5-4 at 2%), and IPA extract treatment added to a fertilizer (0.1% solution of IPA extract with distilled water and 9-5-4 at 2%). Ion fluxes, measured by selective non-invasive microelectrodes, were monitored in leaves. IPA extract significantly enhanced both K+ and Ca2+ fluxes compared to the other treatments. Total dry weight, and macro- and micronutrient contents were subsequently measured. The results showed improved growth in IPA-extract-treated plants, together with a better capacity in accumulating macronutrients, but not micronutrients, in plant organs, especially in leaves. The IPA extract was very effective in inducing water stress tolerance, maintaining a higher leaf water potential and stomatal conductance during the stress period, and inducing a quick recovery in rehydrated plants..