Regulated deficit irrigation (RDI) to save water and improve Sauvignon Blanc quality?

Area of Science:

• Viticulture
• Environmental Science
• Agricultural Engineering

Background:

• Marlborough's land use is shifting from pastoral farming to intensive viticulture.
• This shift necessitates research into sustainable water management practices.

Purpose of the Study:

• To investigate the impact of Regulated Deficit Irrigation (RDI) on Sauvignon Blanc vineyards.
• To assess sustainable water use in response to changing land use.

Main Methods:

• A 5-hectare irrigation research project was established in a Marlborough vineyard.
• Irrigation treatments included control (100% ET(O)), 80%, 70%, and 60% of crop evapotranspiration (ET(O)).
• Sap flow sensors were utilized to monitor vine water needs.

Main Results:

• Over two years with differing climates, irrigation reductions up to 40% showed no significant differences in yield or vegetative growth.
• Sap flow monitoring technology was refined for accurate vine water requirement assessment.

Conclusions:

• Current RDI strategies may offer flexibility in vineyard water management without significant yield loss.
• Accurate sap flow data is crucial for informed irrigation decisions in viticulture.