What is a potential detrimental effect of RDI?

• A. Increased vigor.
• B. Faster ripening.
• C. Lower yield and smaller berries.
• D. Larger berries.

Answer: (C)

RDI works by deliberately reducing irrigation to stress the vines just enough to improve fruit quality. The main downside is that this water deficit often leads to lower yield and smaller berries, because limited water reduces cell expansion and berry growth during development. The timing and severity of the deficit matter a lot—stress during key growth phases can cut yield more than it benefits quality. While mild RDI can concentrate sugars and phenolics, the trade-off is usually a smaller harvest. The other effects listed—more vigor, faster ripening, or larger berries—do not align with what happens under water-lressed conditions; in fact, berry size generally decreases under deficit irrigation.