In this research, effect of drought stress on leaf characteristics was investigated in the experimental field of Miandoab Azad University, Iran using four facultative barley cultivars. Two separate experiments were conducted in pot and field conditions. In both experiments a factorial arrangement was used and the treatments were completely randomized in four replications. In each experiment ha...

During the latter stages of development in fleshy fruit, water flow through the xylem declines markedly and the requirements of transpiration and further expansion are fulfilled primarily by the phloem. We evaluated the hypothesis that cessation of water transport through the xylem results from disruption or occlusion of pedicel and berry xylem conduits (hydraulic isolation). Xylem hydraulic re...

Maximizing crop yield depends on the leaves receiving an optimal supply of water, mineral nutrients, small organic molecules, proteins, and hormones from the root system via the xylem. Soil drying and salinization alter these xylem fluxes, and modern omics techniques offer unparalleled opportunities to understand the complexity of these responses. Although absolute xylem concentrations of any c...

This study was conducted to investigate the effect of altitudinal gradients on  the anatomy of Salvia limbata C.A.Mey. (Lamiaceae). . The S. limbata species were collected from their natural habitats from various regions of West Azerbaijan province in Iran. The thickness of cuticle, collenchymas, phloem, xylem and pith of stem and leaf thickness were measured. Moreover, width, length and number...

As plant tissues dehydrate, water transport efficiency declines, a process typically attributed to air obstruction (embolism) in the xylem. Trifiló et al. (pages 5029– 5039) dissect leaf hydraulic vulnerability and show that both xylem and living tissues may be important. If confirmed and clarified, an important role for outside-xylem hydraulic decline will change our understanding of how plant...

The vulnerability of vascular plants to xylem embolism is closely related to their stable long-distance water transport, growth, and survival. Direct measurements of xylem embolism are required to understand what causes embolism and what strategies plants employ against it. In this study, synchrotron X-ray microscopy was used to non-destructively investigate both the anatomical structures of xy...

Thermospermine, a structural isomer of spermine, is produced through the action of ACAULIS5 (ACL5) and suppresses xylem differentiation in Arabidopsis thaliana. To elucidate the molecular basis of the function of thermospermine, we screened chemical libraries for compounds that can modulate xylem differentiation in the acl5 mutant, which is deficient in thermospermine and shows a severe dwarf p...

Arsenic uptake and translocation studies on xylem sap focus generally on the concentration and speciation of arsenic in the xylem. Arsenic impact on the xylem sap metabolite profile and its production during short term exposure has not been reported in detail. To investigate this, cucumbers were grown hydroponically and arsenate (As(V)) and DMA were used for plant treatment for 24 h. Total arse...

In dicotyledons, biomass predominantly represents cell-wall material of xylem, which is formed during the genetically poorly characterized secondary growth of the vasculature. In Arabidopsis hypocotyls, initially proportional secondary growth of all tissues is followed by a phase of xylem expansion and fiber differentiation. The factors that control this transition are unknown. We observed natu...

Bud break pattern is a key determinant of tree architecture. The mechanisms leading to the precedence of certain buds over the others are not yet fully explained, but the availability of soluble sugars may play a significant role, especially those in the xylem sap at the onset of the growing period. Here, we measured carbon availability in the different tissues (bud, xylem and bark). To assess ...