Morphological and physiological responses of grapevine (Vitis vinifera L.) to drought stress and dust pollution

Dust pollution can negatively affect plant productivity in hot, dry areas with high insolation during summer. To understand the effect of water-deficit and its interaction with dust pollution on vegetative and physiological changes in grapevine ʻBidaneh Sefidʼ, two-year-old plants were subjected to drought stress (-0.1 and -1 MPa) and dust treatment in a greenhouse during 2013 and 2014. The results showed that dust had a significant negative effect on the number of leaves, shoot length, root and shoot dry weights, and total dry weight under both drought and well-irrigated conditions. Dust, when applied in combination with drought, caused severe growth reduction. Leaf relative water content (RWC) and membrane stability index (MSI) were reduced under dust and drought stress, while soluble carbohydrate, proline, malondialdehyde (MDA) and H₂O₂ concentrations increased. Furthermore, dust application resulted in characteristics similar to those induced by water-deficit stress and intensified vegetative and physiological changes when applied together. Dust and drought treatments increased peroxidases and ascorbate peroxidase activities when compared to the control. The results indicate that dust has an adverse effect on the growth and physiology of grapevine and plays a negative role in the response of grapevine to drought stress.