Application of β-aminobutyric acid and spermidine raise drought tolerance and alleviate oxidative stress in potted chrysanthemum

الملخص EN

Potted chrysanthemum is an important flower crop due to its economic value as a commercial pot ornamental plant.

Chrysanthemum growth and development is drastically restricted by water deficit and the available information about
water stress alleviation in chrysanthemum is very limited.

Although β-aminobutyric acid (BABA) and spermidine (Spd)
are involved in drought tolerance, there is no reports about their applications on potted chrysanthemum.

This experiment
was conducted, therefore, to study the impact of BABA or Spd application on drought tolerance of potted chrysanthemum.

Two water levels were used in this experiment i.

e.

100 % FC as well-watered treatment and 50 % FC as drought stress
treatment.

BABA and Spd were each foliar applied at 0.2 or 0.4 mM while untreated plants were sprayed with distilled
water.

Foliar application with BABA or Spd enhanced the growth characters, flower characters, relative water content
(RWC), chlorophyll and proline contents of potted chrysanthemum under drought stress.

Treatment of BABA or Spd
reduced the malondialdehyde (MDA) content, H2O2 production and therefore maintained the membrane integrity in
drought stressed plants.

Additionally, the activities of catalase (CAT) and peroxidaes (POX) enzymes were improved due
to BABA or Spd foliar application in drought stressed plants.

The current results suggest that BABA and Spd were
implicated in drought stress adaptation of potted chrysanthemum through reducing lipid peroxidation, retaining the cell
membrane stability and motivating the antioxidant system