Glucosyltransferase involved in the catabolism of abscisic acid (ABA). Adds a glucosyl group at the C-1 position of ABA; (S)-2-trans-abscisate is a better substrate than the natural (+)-S-abscisate or its enantiomer (-)-R-abscisate. No activity with (-)-phaseic acid (PA), methylated-ABA or with other hormones such as jasmonate, zeatin, auxin (IAA) or gibberellin A3 (GA3). 2-cis-(+)-abscisate + UDP-alpha-D-glucose = beta-D-glucopyranosyl cis-(+)-abscisate + UDP Optimum pH is 6.0-7.3. Belongs to the UDP-glycosyltransferase family.