Effects of abscisic-acid on the leaf stomatal conductance and chilling tolerance in sorghum (Sorghum-bicolor L) eedlings

Abstract

The determination of ABA concentration in xylem sap showed that the exogenously applied ABA could be absorbed rapidly be sorghum roots and translocated to shoots through transpiration stream. The high ABA accumulation after treatment was associated with the induction of stomatal closure. The exogenously applied fluridone, an inhibitor of abscisic acid biosynthesis, reduced ABA accumulation as well as survival rate of chilled sorghum seedling. The above results suggested that the ABA accumulation may be closely involved in the chilling tolerance of sorghum seedlings through the reduction of water inbalance.