Coffee plants respond to drought and elevated [CO2] through changes in stomatal function, plant hydraulic conductance, and aquaporin expression

•Elevated [CO2] led to higher transpiration rates under full irrigation, and lower transpiration under drought.•Varying transpiration patterns were unrelated to maximum stomatal conductance or foliar ABA levels.•Transpiration rates in irrigated plants were linked to varying stomatal closure rate.•Aquaporins may have played key roles in altering stomatal function and hydraulic conductance.•Elevated [CO2] improved plant water status and growth under drought.