Effects of water stress on ethylene evolution from excised leaf segments and intact plants of wheat (Triticum aestivum L. cv Katepwa) were studied. Excised leaf segments of 8 day or 6 week old plants were dried until they lost 8% of their fresh weight (water potential about -2.3 megapascals). These and nondried control leaf segments (water potential about -1.0 megapascal) were sealed in glass t...

Excised leaves and roots of willow (Salix dasyclados Wimm.) accumulated abscisic acid (ABA) in response to desiccation. The accumulation of ABA was greater in young leaves and roots than in old leaves and roots. In mature leaves, ABA accumulation was related to the severity and duration of the desiccation treatment. Water loss equal to 12% of initial fresh weight caused the ABA content of matur...

Cuticular wax deposition and composition affects drought tolerance and yield in plants. We examined the relationship between wax and dehydration stress by characterizing the leaf cuticular wax of tree tobacco (Nicotiana glauca L. Graham) grown under periodic dehydration stress. Total leaf cuticular wax load increased after each of three periods of dehydration stress using a CH2Cl2 extraction pr...

drought stress is the most important factor that reduces yield in crops including chickpea and causes some changes in seed composition. this study was performed in order to evaluate the effects of drought stress and starter nitrogen fertilizer on four cultivars of chickpea. experiment was performed in a split-factorial using randomized complete block design with three replications. drought stre...

Epiphytes are an important component of tropical and subtropical flora, and serve vital ecological functions in forest hydrology and nutrient fluxes. However, they often encounter water deficits because there is no direct contact between their roots and the soil. The strategies employed by epiphytes for maintaining water balance in relatively water-limited habitats are not completely understood...

Salinity is a major abiotic stress that poses great obstacles to wheat production, especially in arid regions. The application of exogenous substances can enhance plant salt tolerance and increase its productivity under salinity stress. This work aimed assess the mechanisms selenium (Se) at different concentrations (2, 4 8 ?M SeCl2) mitigate hazardous impacts toxicity physiological, biochemical...

Hydraulic conductance was measured on leaf and stem segments excised from sugarcane plants at different stages of development. Maximum transpiration rates and leaf water potential (V'L) associated with maximum transpiration were also measured in intact plants as a function of plant size. Leaf specific hydraulic conductivity (LsJ and transpiration on a unit leaf area basis (E) were maximal in pl...

The exchange of HTO with aerial portions of the soybean was studied under a variety of conditions. When fed to a lone leaf or leaflet in a saturated air atmosphere (all other leaves and the growing point having been excised), the HTO profile virtually ceases at a distance of 2 cm from the feeding chamber in the photosynthetic plant, but is greater and more extensive in the unilluminated plant. ...

In this study, two genotypes from the white clover breeding line ‘Syrian selection’, which demonstrates improved survival in summer drought, and two from the white clover cultivar ‘Grasslands Kopu’, a more drought-sensitive cultivar, are compared in terms of their responses to a water deficit. Plants of each genotype were grown in a temperature-controlled glasshouse and a water deficit imposed ...

Regeneration of many late-successional tree species depends on specialized safe sites. The primary objective was to investigate the roles of seedbed and moisture retention as dimensions of safe sites for the early regeneration of drought-sensitive northern white cedar (Thuja occidentalis). We hypothesized that rates of germination, survival, and growth of T. occidentalis are unlikely to differ ...