Hi Ibrahim

First of all, if plant present a water stress the hydralicsystem will be affect. The leaves (responsible for the transpiration) and xylem (transport of water) will present some alterations.

For the leaf alteration in their anatomy. 

http://www.sciencedirect.com/science/article/pii/S030442380200016X

http://www.jstor.org/discover/10.2307/2475281?sid=21105412119971&uid=4&uid=3737664&uid=2

The vessels element diameter also dicrease in seize (see the attached file)

I hope this information help you

In addition, the water defecit have a great impact on the genomic structure in plants too. Those genomic changes subsequently could affect the anatomy in the long run . See attached article

Article Water Deficit Induction of Copia and Gypsy Genomic Retrotransposons

hi Ibrahim, as i know there's many changes on plant anatomy as effect of water stress, some of plants structure could be changes such as  xylem, phloem etc.

i think your question need more specific.

regards,

Water stress markedly affected the anatomical features in flag leaves of both wheat cultivars. It caused massive decreases (P< 0.05) in the leaf thickness, ground tissue thickness, number of hairs, metaxylem vessel area, xylem vessel area, phloem tissue area, vascular bundle area, number of motor cells as well as number of opened stomata on both upper and lower epidermis. On the other hand, water stress increased (P< 0.05) the number of hairs and closed stomata on both upper and lower epidermis in flag leaves of the two wheat cultivars. The magnitude of decrease in all anatomical features in flag leaf was more pronounced with the sensitive cultivar. Furthermore, water stress led to a marked decrease (P< 0.05) in peduncle diameter, tracheids area, metaxylem vessel area, xylem tissue area,

phloem tissue area, vascular tissue area, number of vascular bundles as well as opened stomata but increased the number of hairs and closed stomata on the peduncle surface of the two wheat cultivars.

Conductive canals between source and sink in wheat cultivars play a prominent role in translocating the photosynthates to the developing grains . Anatomical changes induced by water deficits in higher plants were better-observed indicators, which can be directly applied to agriculture and handled. To aim at exploring efficient anatomical indices, much information has been documented, but more attention should be paid to link them with physiological and molecular one .

In principal, the production of cereal grains is directly correlated to the growth of shoot as the main factory in which assimilates are produced. However, the photosynthetic ability of these shoots depends mainly on their pigments content . Considering the conclusion of Egeli et al. (1985) that the accumulation of dry matter in the grains requires the production of assilates in the leaves, their translocation to the rachilla of the spikelets, movement into the endosperm and embryo of the grain and synthesis of materials to be stored. Leaf structure seems to be of great importance in the regard. Thus conductive canals between source and sink in wheat cultivars have been reported to the developing grains .

In water-stressed barley, wheat and horse bean plants the diameter of xylem vessels decreased noticeably. In addition the thickness of the walls of the conduction path in leaves, stems and roots increased resulting in inhibition of further transport .

Dear Ibrahim,

Your question is too general, plants are adapted to many stress factors in different way and not of them share the same adaptations. Some of this adaptations are metabolic, not only morphologic. Please, could you focus your question?

Water deficit or stress in plants leads to many anatomical  changes followed by specific physiological responses in plants.  Other than xylem and  phloem vessel's structural alterations there is a significant  negative development in xylem conductivity  in woody species. The important feature is xylem cavitation or xylem embolism leads to plugging of xylem followed by failure of water conductance. In such cases the recovery is very poor.

Dear Ibrahim Abd El Khalek Abd El Mola

Anatomical adaptations depends of each plant specie.  I suggest you the reading of the attached article. It´s very guideline and helps me in my anatomical analysis (despite my treatments were plant response to saline stress).

Best for you and regards from Argentina

Rosalia

Changes in plant anatomy exposed to water stress depends upon plant species, there are no two thoughts about it . but , broadly , if you classify the plant in two major categories , one water stress tolerant and another water stress susceptible ones, both exhibit quite distinct changes in plant  anatomy when exposed to water deficit stress.  The first change , I consider that will immediately appear is with regard to organisation of chloroplast as photosynthetic apparatus, cell wall thickness, size and layering of mesophyll cells of leaves etc. , in addition to root configuration / root architectural development ( For example , better development of tertiary roots over secondary roots or extension of tap root ), depending upon the plant species . Changes in root density could be taken as one very effective indicator of plant anatomical changes.

.

Hi.

In plant anatomy many features can change in water stress conditions. If the stress is by water deficit the cuticle can become thinck for reduce the water loss, for example. But if the stress is by overflow the plant will change the morphological features to allow the aeration of the its tissues.

Dear Ibrahim Abd El Khalek Abd El Mola,

Please also have a look at these useful ResearchGate links.

Chapter Water Stress in Plants: Causes, Effects and Responses

Article Anatomical adaptations of Astragalus gombiformis Pomel. unde...

Chapter Water Stress: Morphological and Anatomical Changes in Soybea...

Article Comparative impacts of water stress on the leaf anatomy of a...

Article Effect of Drought Stress on Anatomical Structure and Chlorop...

Article Root Anatomical, Physiological, and Morphological Responses ...

Article Morpho-Anatomical Changes in Roots of Chickpea (Cicer arieti...

Article Effects of water stress during growth of xylem anatomy, xyle...

Article Water stress affects leaf anatomy, gas exchange, water relat...

Article Water-deficit stress—Induced anatomical changes in higher plants

Article Water Stress Induced Changes in Anatomy of Tomato Leaf Epidermes

Article Drought Stress Effects on Root Anatomical Characteristics of...

Good luck!