Long-term behavioral and biochemical consequences of under-water stress in the rat

Long-term induced water stress in field-grown grapevine leads to a progressive decline of stomatal conductance, accompanied by a decrease in CO 2 assimilation (40%). The apparent quantum yield also decreases (59%), which may reflect a relative increase in alternative processes for electron consumption. There is also a shift to non-stomatal regulation, as judged from significant depletions (37%) in maximum photosynthesis rate at saturating CO 2 related to limited ribulose biphosphate (RuBP) regeneration, whereas small, non-significant effects are observed on carboxylation efficiency. A high correlation (87%) between photosynthesis and stomatal conductance is observed for all experimental data and declines in intercellular CO 2 concentration parallel reductions in stomatal conductance. The data show that field response of grapevines to increasing soil water deficit involves stomatal and non-stomatal effects but, due to gradually induced drought, regulation mechanisms able to adjust mesophyll capacity to the average CO 2 supply. The non-stomatal adjustment seems to be exerted mainly in metabolic pathways related with the RuBP regeneration. Contrasting characteristics were observed for both cultivars. Tempranillo exploited the non-stressful conditions successfully, whereas Manto Negro, responding to its reputation as more drought resistant, showed a higher intrinsic water use efficiency, particularly for low water availability. This advantage seems to be due to lower non-stomatal limitations.

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Long-term water stress leads to acclimation of drought sensitivity of photosynthetic capacity in xeric but not riparianEucalyptusspecies

Annals of Botany ◽

10.1093/aob/mcv161 ◽

2015 ◽

Vol 117 (1) ◽

pp. 133-144 ◽

Cited By ~ 34

Author(s):

Shuang-Xi Zhou ◽

Belinda E. Medlyn ◽

Iain Colin Prentice

Keyword(s):

Water Stress ◽

Photosynthetic Capacity ◽

Drought Sensitivity

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The impact of drought stress on the yields and food value of selected forage grasses

Acta Agrobotanica ◽

10.5586/aa.1663 ◽

2016 ◽

Vol 69 (2) ◽

Cited By ~ 4

Author(s):

Mariola Staniak

Keyword(s):

Soil Moisture ◽

Water Stress ◽

Drought Stress ◽

Dry Matter ◽

Nutritional Value ◽

Lolium Multiflorum ◽

Grass Species ◽

Forage Grasses ◽

The Impact

The aim of the study was to compare yields and nutritional value of selected species and cultivars of forage grasses under the optimal moisture conditions and long-term drought stress. The regenerative capacity of plants after dehydration was also assessed. The pot experiment was conducted in years 2009–2010 in IUNG-PIB’s greenhouse in Puławy, Poland. Nine cultivars of four species: Dactylis glomerata (‘Amera’, ‘Minora’), Festuca pratensis (‘Skra’, ‘Fantazja’), Festulolium braunii (‘Felopa’, ‘Agula’, ‘Sulino’), and Lolium multiflorum (‘Gisel’, ‘Lotos’) were investigated in well-watered conditions (70% field water capacity – FWC) and under a long-term drought stress (40% FWC).The study showed that stress caused by soil moisture deficiency significantly reduced yields of D. glomerata, F. pratensis, F. braunii, and L. multiflorum. The total yield of dry matter under stress conditions was about 31% lower, compared to the performance achieved on the optimally moisturized treatment. The smallest reduction in dry matter yield under the conditions of water deficit was recorded for D. glomerata, which makes it the most resistant to stress, followed by F. pratensis. The resistance of F. braunii and L. multiflorum to stress was similar and significantly lower. There was a various response of different grasses to the water stress. On the basis of the value of the DSI (drought susceptibility index), the tested cultivars were ranked depending on the sensitivity to drought, starting with the most resistant cultivar: ‘Minora’, ‘Skra’, ‘Fantazja’, ‘Amera’, ‘Sulino’, ‘Agula’, ‘Gisel’, ‘Lotos’, and ‘Felopa’. The digestibility of dry matter and nutrient value of the grasses depended on both the level of soil moisture and grass species. Under the water stress, the digestibility and protein value increased compared to the control objects. Lolium multiflorum and F. braunii had the best nutritional value, while D. glomerata – the weakest.

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Long-Term Correlation between Water Deficit and Quality Markers in HydroSOStainable Almonds

Agronomy ◽

10.3390/agronomy10101470 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1470 ◽

Cited By ~ 1

Author(s):

Leontina Lipan ◽

Marina Cano-Lamadrid ◽

Francisca Hernández ◽

Esther Sendra ◽

Mireia Corell ◽

...

Keyword(s):

Fatty Acids ◽

Water Stress ◽

Dry Weight ◽

Quality Parameters ◽

Added Value ◽

Total Sugars ◽

Quality Markers ◽

Almond Trees ◽

Positive Correlations

Global warming enhances the rainfall and temperature irregularity, producing a collapse in water resources and generating an urgent need for hydro-sustainable thinking in agriculture. The aim of this study was to evaluate the correlation between the water stress of almond trees and quality parameters of fruits, after 3 years of experiments, with the objective of establishing quality markers necessary in the certification process of hydroSOStainable almonds. The results showed positive correlations among the stress integral (SI) and dry weight, color coordinates (L*, a* and b*), minerals (K, Fe, and Zn), organic acids (citric acid), sugars (sucrose, fructose, and total sugars), antioxidant activity, and fatty acids [linoleic acid, polyunsaturated (PUFA)/monounsaturated (MUFA) ratio, PUFA and SFA, among others]. As well as negative correlations of SI with water activity, weight (almond, kernel, and shell), kernel size, minerals (Ca and Mg), fatty acids (oleic acid, oleic/linoleic ratio, MUFA, and PUFA/SFA ratio), and sensory attributes (size, bitterness, astringency, benzaldehyde, and woody). Finally, this research helped to prove key quality parameters that can be used as makers of hydroSOStainable almonds. In addition, it was demonstrated that controlling water stress in almond trees by using deficit irrigation strategies can lead to appropriate yields, improve the product quality, and consequently, lead to a final added value.

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Leaf Water Status in Velvetleaf under Long-term Interactions of Water Stress, Atmospheric Humidity, and Carbon Dioxide

Journal of Plant Physiology ◽

10.1016/s0176-1617(11)80377-9 ◽

1992 ◽

Vol 139 (5) ◽

pp. 600-604 ◽

Cited By ~ 5

Author(s):

Yao-Hua Luo ◽

Boyd R. Strain

Keyword(s):

Carbon Dioxide ◽

Water Stress ◽

Water Status ◽

Leaf Water ◽

Atmospheric Humidity ◽

Leaf Water Status

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The influence of water stress on the growth and development of Townsville stylo (Stylosanthes humilis) in pure ungrazed swards at Katherine, Northern Territory

Australian Journal of Experimental Agriculture ◽

10.1071/ea9770598 ◽

1977 ◽

Vol 17 (87) ◽

pp. 598 ◽

Cited By ~ 2

Author(s):

MJ Fisher ◽

NA Campbell

Keyword(s):

Water Stress ◽

The Other ◽

Stylosanthes Humilis ◽

Relative Water ◽

Influence Of Water ◽

Leaf Relative Water Content ◽

Final Yield ◽

Townsville Stylo ◽

Effect On Yield

In order to understand more fully the effect of water stress on the growth of Townsville stylo (Stylosanthes humilis) (TS), five drought treatments, imposed by the use of rain shelters, were compared with an unstressed control in a field experiment. Droughts were imposed during the early vegetative (EV) and late vegetative (LV) stages, and during flowering (F) until leaf relative water content at 2.30 p.m fell to 60 per cent. Further unrelieved drought was re-applied to these three treatments when seeding was well advanced. The other two treatments were subjected to unrelieved drought, one starting at late flowering (LF) and the other seeding (S). The drought treatments had no effect on the final yield of dry matter compared with the control. Stress during the vegetative stage reduced growth, but the relief of stress was followed by a period of rapid growth which largely compensated for the loss. However, because the EV stress killed 40 per cent of the sward (the plants were unable to use water from depths below 75-1 00 cm), the compensatory phase in this treatment was less marked, but more sustained. Because of the decline in growth rate with approaching maturity, stresses during and after flowering had little effect on yield. Stress during vegetative growth hastened flowering by two weeks; however, pod yields were only reduced in the LF treatment. In general these observations demonstrate important aspects of the plants' good adaptation to the dry monsoonal tropics, and explain its stable long-term yields when maintained in near-pure swards.

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