Abscisic acid, and abscisic acid-induced water stress tolerance in mycorrhizal herbaceous and olive (Olea europaea) plants

The worldwide expansion of drought-affected areas has a negative effect on crop yield and production, making water stress the most significant abiotic stress, limiting plant growth and development. The use of arbuscular mycorrhizal fungi (AMF) is a strategy that mitigates the effects of this kind of stress in a sustainable way, which occurs due to the increased tolerance to water stress in plants inoculated with these fungi. Modern agriculture is facing the challenge of ensuring global food demand. However, climate change is causing an increase in temperature that leads to severe droughts in some areas. Numerous biotechnological techniques are being used to overcome this drought stress. Among them, the use of AMF is considered an efficient approach to mitigate such stress. AMF provide water stress tolerance through biochemical and physiological mechanisms. Some of the well-known mechanisms include modification of hormonal balances comprising strigolactones, abscisic acid, gibberellic acid, salicylic acid, and jasmonic acid. The symbiosis of AMF changes the expression of the aquaporins (water transporting channels) present in the plasma membrane and tonoplast, improving plant water status.