Effects of Abscisic Acid on Morphological and Physiological Responses to Water Stress in Eucalyptus camaldulensis Seedlings

1991 ◽  
Vol 18 (2) ◽  
pp. 153 ◽  
Author(s):  
A Gibson ◽  
KT Hubick ◽  
EP Bachelard
Keyword(s):  
Abscisic Acid ◽  
Water Stress ◽  
Stress Responses ◽  
Morphological Changes ◽  
Morphological Characteristics ◽  
Eucalyptus Camaldulensis ◽  
Leaf Nitrogen ◽  
Northern Territory ◽  
Leaf Transpiration ◽  
Eucalyptus Camaldulensis Dehnh

The effects of abscisic acid (ABA) and a subsequent water stress on the physiological and morphological characteristics of seedlings of three provenances of Eucalyptus camaldulensis Dehnh. grown in pots in a glasshouse were compared 56 days after application of ABA. Seedlings from a high rainfall monsoon provenance in the dry tropics (Katherine, Northern Territory, Australia) were largely unaffected by ABA or by water strees in either physiological or morphological characteristics. Seedlings from a lower rainfall monsoon provenance in the humid tropics (Petford, Queensland) responded to water stress by reducing gas exhange while increasing photosynthetic capacity, indicated by increased leaf nitrogen and chlorophyll concentrations, and both short- and long-term leaf transpiration efficiency, indicated by changes in carbon-isotope discrimination. The changes were largest when ABA was also applied. Seedlings from semi-arid Tennant Creek (Northern Territory), which had the highest assimilation rates overall, responded to both ABA and water stress primarily by morphological changes including suppression of apical growth and increase in specific leaf weight. The results are discussed in terms of specific adaptations for establishment in increasingly dry environments and the possible role of ABA in mediating stress responses.

A comparison of the stress responses of Zea mays seedlings as shown by qualitative changes in protein synthesis

1988 ◽  
Vol 66 (9) ◽  
pp. 1883-1890 ◽  
Author(s):  
P. C. Bonham-Smith ◽  
M. Kapoor ◽  
J. D. Bewley
Keyword(s):  
Protein Synthesis ◽  
Abscisic Acid ◽  
Water Stress ◽  
Heat Shock ◽  
Stress Responses ◽  
Protein Profile ◽  
Tissue Response ◽  
Specific Proteins ◽  
Induced Proteins ◽  
Qualitative Changes

Maize seedlings respond to heat shock, water stress, abscisic acid treatment, and wounding with the synthesis of stress-specific proteins. Unlike the almost instantaneous (10 min) heat-shock response, a much longer stress exposure is required before the synthesis of water stress induced, abscisic acid induced, or wound-induced proteins. As with heat shock, the protein profile of 24 h water stress induced proteins is consistent between tissue types, whereas seedling tissue response to wounding or heavy metals varies. Wounding of the mesocotyl for 12 h or more results in a complex change (induction and inhibition) in protein synthesis in the growing region, while protein synthesis in the nongrowing region is affected to a much lesser extent.

Xylem Permeability and Embolism Susceptibility in Seedlings of Eucalyptus camaldulensis Dehnh. From Two Different Climatic Zones

1995 ◽  
Vol 22 (1) ◽  
pp. 15 ◽  
Author(s):  
PJ Franks ◽  
A Gibson ◽  
EP Bachelard
Keyword(s):  
Eucalyptus Camaldulensis ◽  
Air Permeability ◽  
Northern Territory ◽  
Hydraulic Architecture ◽  
Climatic Zones ◽  
Stem Wood ◽  
Flow Simulations ◽  
Specific Permeability ◽  
Eucalyptus Camaldulensis Dehnh ◽  
Branch Wood

We examined the hydraulic architecture of Eucalyptus camaldulensis seedlings from two climatically different provenances: Petford in north Queensland, which is humid; and Tennant Creek in the Northern Territory, which is semi-arid. Xylem liquid specific permeability (Kg) was calculated from measurements of xylem air permeability (Kg) and hydraulic resistances (R) were also calculated. Embolism susceptibility curves were constructed by measuring Kg in the stems of young seedlings. Canopy leaf areas were mapped and sap flows through the Tennant Creek and Petford seedlings were simulated. Results showed that the permeability of stem wood in the Tennant Creek seedling was about 40% higher than in Petford, and the permeability of its branch wood was about 25% higher. The threshold water potential for initiation of embolisms (Ψt) was slightly lower in Tennant Creek seedlings (- 3.3 MPa compared with - 3.0 MPa) and the number of embolisms with decreasing Ψ was lower for Tennant Creek seedlings. Sap flow simulations showed differences in the distribution of water throughout the seedling canopies. The results are discussed in terms of the ecology of the two eucalypt provenances.

ALTURA E SOBREVIVÊNCIA DE Eucalyptus camaldulensis Dehnh EM DIFERENTES ESPAÇAMENTOS AOS 14 MESES APÓS PLANTIO EM CAMPO EM ALVORADA DO GURGUÉIA –PIAUÍ

2018 ◽  
Author(s):  
Silva Raynara Ferreira da ◽  
Sousa Moema Barbosa de ◽  
Silva Aluísio Costa ◽  
Marinho Eduardo Silva ◽  
Dias Bruna Anair Souto
Keyword(s):  
Eucalyptus Camaldulensis ◽  
Eucalyptus Camaldulensis Dehnh

Characteristics of the course of nephritis associated with Iga-vasculitis Henoch-Schoenlein in children

2020 ◽  
Vol 24 (3) ◽  
pp. 64-71
Author(s):  
A. V. Sukalo ◽  
I. A. Kazyra
Keyword(s):  
Clinical Laboratory ◽  
Morphological Changes ◽  
Pediatric Nephrology ◽  
Morphological Characteristics ◽  
Lymphocyte Activation ◽  
Renal Tissue ◽  
Kidney Damage ◽  
Iga Vasculitis ◽  
Factors Affecting ◽  
Treatment Regimens

INTRODUCTION. Among systemic vasopathies in children, IgA vasculitis Henoch Schoenlein (HS) is the most common, according to various authors, kidney damage is noted in 25-80 % and usually determines the prognosis of the disease.THE AIM of the study was to analyze clinical, laboratory, immunological, morphological characteristics, features of the course and treatment of nephritis associated with IgA vasculitis HS in children, as well as factors affecting the prognosis.PATIENTS AND METHODS. The study included 31 patients with morphologically verified nephritis due to IgA vasculitis HS (18 – boys, 13 – girls) aged 3 to 17 years, who were monitored at the Nephrology Department of the "2nd Children's City Clinical Hospital" of the National Center for Pediatric Nephrology and Renal Replacement therapy in Minsk from 2010 to 2019 yrs.The following parameters were analyzed: the clinical variant of kidney damage, laboratory tests (including the study of BAFF, RANTES lymphocyte activation molecules, pro-inflammatory IL1β, caspase1, TNFα, growth factors VEGF, TGF), 24 hours monitoring and office blood pressure measurements, ECHO cardiography with indicescalculation, ultrasound of the carotid arteries with the thickness of intima-media complex, morphological changes in the renal tissue, as well as treatment regimens.RESULTS. The contribution of deGal-IgA1, markers of T and B lymphocytes activation, pro-inflammatory and profibrotic molecules in the development of the disease is shown. Arterial hypertension was registered in 42 % of children, signs of heart remodeling according to the calculated indices in 19,3 %. Decrease level of adiponectin, vitamin D, leptin, increase concentration of obestatin, Pro-BNP, hs-CRP, and TSAT indicator classify patients with nephritis due to IgA vasculitis HS at moderate risk for the developmentof cardio-vascular disorders, which suggests the need for timely correction.CONCLUSION. In most cases, nephritis with IgA vasculitis HS has a benign course with rare relapses and progression to the end stage of chronic kidney disease (6,5 %).

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