scholarly journals Different levels of water deficit induces changes in growth pattern but not in chlorophyll fluorescence and water relations of Hancornia speciosa Gomes seedlings

2016 ◽  
Vol 12 (2) ◽  
Author(s):  
Elizamar Ciríaco Da Silva ◽  
Tiago Buarque Prado ◽  
Rebeca Nogueira De Alcântara ◽  
Carlos Dias Da Silva Junior ◽  
Luis Carlos Nogueira
Keyword(s):  
Chlorophyll Fluorescence ◽  
Water Stress ◽  
Water Deficit ◽  
Quantum Efficiency ◽  
Water Relations ◽  
Growth Pattern ◽  
Field Capacity ◽  
Water Levels ◽  
Relative Water ◽  
Hancornia Speciosa

The tree Hancornia speciosa Gomes is commonly known in Brazil as “mangabeira”, the fruit of which has high nutritional value. The knowledge about its physiology is still scarce, mainly during the initial phase of development. Thus, the aim of the present study was to evaluate the effects of different water deficit levels on growth pattern, chlorophyll fluorescence and water relations in H.speciosa seedlings. A A factorial experimental design (water treatment x evaluation time) was used with four water treatments based on the field capacity (FC) (80%, 60%, 40% and 20%) with five replications. Plant height, number of leaves, stem diameter, dry biomass production and partitioning, quantum efficiency of photosystem II (PSII), water potential (Ψw), relative water content (RWC), carbohydrates, proteins and proline content were analyzed. Severe water stress (20% FC) led to a reduction in growth and altered the biomass partitioning pattern in the seedlings. However, water relations were not significantly affected, as the seedlings maintain high Ψw and RWC without significant increase in organic solutes content when cultivated in 20% FC. Moreover, the quantum efficiency of PSII was unaffected by the different water levels, suggesting a lack of photoinhibition due to water stress. The change in growth pattern, with an increase in root depth and reduction in shoot emission, seems to be the main strategy of the H. speciosa seedlings for the maintenance of tissue hydration throughout periods of water deficit.

The effect of water deficit on some physiological indices of Indian lettuce (Lactuca indica L.)

2021 ◽  
Vol 66 (1) ◽  
pp. 80-86
Author(s):  
Thin Pham Thi Thanh ◽  
Bang Cao Phi ◽  
Hai Nguyen Thi Thanh ◽  
Khuynh Bui The ◽  
Mai Nguyen Phuong ◽  
...  
Keyword(s):  
Chlorophyll Fluorescence ◽  
Water Stress ◽  
Water Content ◽  
Flowering Time ◽  
Water Deficit ◽  
Physiological Responses ◽  
Water Deficit Stress ◽  
Flower Formation ◽  
Lactuca Indica ◽  
Wilting Rate

Indian Lettuce (Lactuca indica L.) is a valuable medicinal herb but there are still no many researches about this plant. In this work, the physiological responses of Indian lettuce plants under water deficit conditions (5, 8, and 11 days of water stress) were investigated. The Indian lettuce wilted after 5 days of water stress (66.66%), the wilting rate increased after 8 (93.33%) and 11 days (100%) of water stress. The longer duration of water deficit stress caused the slower recovery of plants after rewatering. The water deficit stress caused a decrease in chlorophyll fluorescence, non-associated water content as well as flower formation of Indian lettuce. But the water deficit stress increases the associated water content and the flowering time of this plant.

scholarly journals The Epiphytic FernElaphoglossum luridum(Fée) Christ. (Dryopteridaceae) from Central and South America: Morphological and Physiological Responses to Water Stress

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Bruno Degaspari Minardi ◽  
Ana Paula Lorenzen Voytena ◽  
Marisa Santos ◽  
Áurea Maria Randi
Keyword(s):  
Water Stress ◽  
Water Deficit ◽  
Chlorophyll A ◽  
Tca Cycle ◽  
Photosynthetic Parameters ◽  
Relative Water ◽  
Physiological Studies ◽  
Cycle Regulation ◽  
Epiphytic Fern ◽  
Chlorophyll A Content

Elaphoglossum luridum(Fée) Christ. (Dryopteridaceae) is an epiphytic fern of the Atlantic Forest (Brazil). Anatomical and physiological studies were conducted to understand how this plant responds to water stress. TheE. luridumfrond is coriaceus and succulent, presenting trichomes, relatively thick cuticle, and sinuous cell walls in both abaxial and adaxial epidermis. Three treatments were analyzed: control, water deficit, and abscisic acid (ABA). Physiological studies were conducted through analysis of relative water content (RWC), photosynthetic pigments, chlorophyll a fluorescence, and malate content. No changes in RWC were observed among treatments; however, significant decreases in chlorophyll a content and photosynthetic parameters, including optimal irradiance (Iopt) and maximum electron transport rate (ETRmax), were determined by rapid light curves (RLC). No evidence of crassulacean acid metabolism (CAM) pathway was observed inE. luridumin response to either water deficit or exogenous application of ABA. On the other hand, malate content decreased in theE. luridumfrond after ABA treatment, seeming to downregulate malate metabolism at night, possibly through tricarboxylic acid (TCA) cycle regulation.

scholarly journals Differential Activity of Antioxidant Enzymes and Physiological Changes in Wheat (Triticum aestivum L.) Under Drought Stress

2019 ◽  
Vol 11 (2) ◽  
pp. 266-276
Author(s):  
Kamal MIRI-HESAR ◽  
Ali DADKHODAIE ◽  
Saideh DOROSTKAR ◽  
Bahram HEIDARI
Keyword(s):  
Water Stress ◽  
Drought Stress ◽  
Field Capacity ◽  
Triticum Aestivum L ◽  
Plant Production ◽  
Breeding Programs ◽  
Drought Tolerant ◽  
Severe Water Stress ◽  
Significant Difference ◽  
Relative Water

Drought stress is one of the most significant environmental factors restricting plant production all over the world. In arid and semi-arid regions where drought often causes serious problems, wheat is usually grown as a major crop and faces water stress. In order to study drought tolerance of wheat, an experiment with 34 genotypes including 11 local and commercial cultivars, 17 landraces, and six genotypes from International Maize and Wheat Improvement Center (CIMMYT) was conducted at the experimental station, School of Agriculture, Shiraz University, Iran in 2010-2011 growing season. Three different irrigation regimes (100%, 75% and 50% Field Capacity) were applied and physiological and biochemical traits were measured for which a significant difference was observed in genotypes. Under severe water stress, proline content and enzymes’ activities increased while the relative water content (RWC) and chlorophyll index decreased significantly in all genotypes. Of these indices, superoxide dismutase (SOD) and RWC were able to distinguish tolerant genotypes from sensitives. Moreover, yield index (YI) was useful in detecting tolerant genotypes. The drought susceptibility index (DSI) varied from 0.40 to 1.71 in genotypes. These results indicated that drought-tolerant genotypes could be selected based on high YI, RWC and SOD and low DSI. On the whole, the genotypes 31 (30ESWYT200), 29 (30ESWYT173) and 25 (Akbari) were identified to be tolerant and could be further used in downstream breeding programs for the improvement of wheat tolerance under water limited conditions.

Phenology, leaf gas exchange, growth, and seed yield in contrasting Medicago truncatula and Medicago laciniata populations during prolonged water deficit and recovery

Botany ◽  
2012 ◽  
Vol 90 (2) ◽  
pp. 79-91 ◽  
Author(s):  
Nasreddine Yousfi ◽  
Ines Slama ◽  
Chedly Abdelly
Keyword(s):  
Water Deficit ◽  
Medicago Truncatula ◽  
Seed Yield ◽  
Growth Parameters ◽  
Leaf Gas Exchange ◽  
Seed Mass ◽  
Field Capacity ◽  
Water Shortage ◽  
Relative Water ◽  
Leaf Relative Water Content

The aims of this study were to investigate the effect of prolonged water stress and recovery on phenology, growth, and seed yield in Tunisian contrasting populations of Medicago truncatula and Medicago laciniata . After ample irrigation for 24 days, the plants of each population were divided into two lots: the first lot was irrigated at 100% field capacity (FC), and the second at only 45% FC. After 24 days of treatment, one lot of dehydrated plants was rewatered at 100% FC, while the other was maintained at 45% FC. Interspecific and intraspecific differences were found in phenological responses to water deficit. All growth parameters were more reduced in M. truncatula populations than in M. laciniata populations. The water shortage tolerance of M. laciniata populations was associated with a lower metabolic impairment of photosynthesis and maintenance of relatively higher leaf relative water content. Seed yield was also more reduced in M. truncatula populations compared with M. laciniata populations. In M. laciniata, seed mass was a compensation mechanism to sustain seed yield under drought conditions. Seed yield variation between populations under water deficit was explained mainly by variation in seed number per plant.

scholarly journals Short-Time of Rehydration is not Effective to Re-Establish Chlorophyll Fluorescence and Gas Exchange in Two Cowpea Cultivars Submitted to Water Deficit

2017 ◽  
Vol 45 (1) ◽  
pp. 238-244 ◽  
Author(s):  
Udson de Oliveira BARROS JUNIOR ◽  
Maria Antonia Machado BARBOSA ◽  
Michael Douglas Roque LIMA ◽  
Gélia Dinah Monteiro VIANA ◽  
Allan Klynger da Silva LOBATO
Keyword(s):  
Chlorophyll Fluorescence ◽  
Water Stress ◽  
Gas Exchange ◽  
Water Supply ◽  
Water Deficit ◽  
Water Restriction ◽  
Cowpea Cultivars ◽  
The Third ◽  
Short Time

Low water supply frequently interferes on chlorophyll fluorescence and gas exchange. This study aimed to answer if a short-time of rehydration is efficient to re-establish chlorophyll fluorescence and gas exchange in cowpea plants. The experiment used four treatments (sensitive / water deficit, sensitive / control, tolerant / water deficit and tolerant / control). The sensitive and tolerant cultivars after water restriction had significant changes in gas exchange. On the third day, the stress caused lower for PN and gs in sensitive cultivar of 67% and 45%, respectively. After rehydration these parameters were not recovered significantly to two cultivars. In relation to chlorophyll fluorescence, water stress caused significant changes in all parameters evaluated of cultivars, being observed effects more intense on sensitive cultivar in the parameters Fv/Fm (38%) and Fo (69%). Rehydration did not promote recovery of the values of Fv/Fm and Fo to sensitive cultivar. Therefore, our study revealed that a short-time of rehydration is not effective to re-establish chlorophyll fluorescence and gas exchange in cowpea plants submitted to water deficit.

scholarly journals Water Relations of a Fragaria chiloensis and a F. virginiana Selection during and After Water Deficit Stress

1993 ◽  
Vol 118 (2) ◽  
pp. 274-279 ◽  
Author(s):  
Baolin Zhang ◽  
Douglas D. Archbold
Keyword(s):  
Water Deficit ◽  
Water Relations ◽  
Osmotic Potential ◽  
Dark Period ◽  
Water Deficit Stress ◽  
Subsequent Recovery ◽  
Fragaria Chiloensis ◽  
Relative Water ◽  
And Control ◽  
Selection Of

A comparative study was performed to elucidate changes in the water relations of Fragaria chiloensis (L.) Duch. `BSP14' (FC) and F. virginiana (L.) Duch. `NCC85-13V' (FV), grown in containers in a greenhouse, in response to imposed water deficit stress and subsequent recovery. At incipient wilting, a reduction in osmotic potential at full turgor (Ψπ100 of 0.42 MPa occurred in leaves of FC, while no change was found in FV. Leaf water potential (Ψ) isotherms revealed that as leaf Ψ and relative water content (RWC) declined, stressed FC plants maintained a higher turgor potential (ΨP) and lower osmotic potential (Ψπ) than nonstressed (control) plants, while there was no effect of drought stress on these relationships in the FV plants. From the isotherms, turgor loss was estimated to occur at a lower leaf Ψ and RWC in stressed FC plants than either in control FC plants or stressed and control FV plants. During a diurnal phase 36 hours after wilting, leaf Ψ, Ψπ and RWC of the FC selection were generally lower in stressed than in control plants, with differences ranging from 0.14 to 0.74 MPa, 0.28 to 0.47 MPa, and 1% to 8%, respectively. In the FV selection, Ψπ was 0.09 to 0.31 MPa lower in stressed than in control leaves, while the other characteristics were not affected. Leaf ΨP, of stressed FC plants was 0.09 to 0.27 MPa higher than controls during the dark period, but was similar during the day. When plants of both species were grown and stressed in the same container, FV plants wilted ≈4 days earlier than FC plants, and foliar Ψπ100 of FC was 0.35 MPa lower than that of FV at incipient wilting. The isothermal relationships between leaf Ψ and Ψπ100 indicated FC had a Ψπ100 ≈ 0.25 MPa lower than FV at a Ψ <1.5 MPa. This study provided evidence for greater osmotic adjustment in response to imposed water deficit stress in a selection of F. chiloensis than in one of F. virginiana.

scholarly journals ↵​Impact of A Selected Mycorrhizal Complex and A Rhizobacterial Species on Tomato Plants’ Growth under Water Stress Conditions

2021 ◽  
Author(s):  
Slimani Afafe ◽  
Harkousse Oumaima ◽  
Mazri Mouaad Amine ◽  
Zouahri Abdelmajid ◽  
Ouahmane Lahcen ◽  
...  
Keyword(s):  
Water Stress ◽  
Mycorrhizal Fungi ◽  
Growth Parameters ◽  
Water Status ◽  
Field Capacity ◽  
Water Levels ◽  
Stress Conditions ◽  
Bacillus Sp ◽  
Tomato Plants ◽  
The Impact

Background: Plant strategies for adapting to drought could be improved by associations between plant roots and soil microorganisms, including arbuscular mycorrhizal fungi (AMF) and plant growth promoting rhizobacteria (PGPR). In this study, the impact of a selected AMF complex and a selected PGPR species on the growth of tomato (Lycopersicum esculentum Mill.) under induced water stress was evaluated. Methods: Three different inoculation treatments were applied to tomato seedlings (a complex of AMF composed mainly of Glomus genus a Bacillus sp. PGPR treatment and a combination of both) and three different water levels (75%, 50% and 25% of field capacity). Result: A significant damaging impact of drought on tomato growth parameters and root mycorrhizal colonization, although the presence of microbes stimulated tomato plants growth and decreased the impact ofdrought stress. Indeed inoculated plants presented greater heights, fresh and dry weights, leaves number and area; greater water status; and greater proteins, sugars and chlorophylls contents either with the AMF complex or the Bacillus sp. in normal and drought stress conditions compared to the non-inoculated plants. However dual inoculation recorded the highest values under all water levels treatments.

scholarly journals Adaptation of Cowpea (Vigna unguiculata (L.) Walp.) to Water Deficit during Vegetative and Reproductive Phases Using Physiological and Agronomic Characters

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Vincent Ezin ◽  
Artoche Gloria Christelle Tosse ◽  
Ifagbémi Bienvenue Chabi ◽  
Adam Ahanchede
Keyword(s):  
Water Stress ◽  
Drought Stress ◽  
Water Deficit ◽  
Vigna Unguiculata ◽  
Agronomic Traits ◽  
International Institute ◽  
Relative Water ◽  
Cowpea Varieties ◽  
Reproductive Phases ◽  
Water Treatments

Cowpea (Vigna unguiculata (L.) Walp.) is an important commodity in West Africa. Its seeds are a valuable source of protein, vitamins, and income for humans. However, cowpea cultivation in Benin faces climatic constraints such as water stress caused by a prolonged absence of rain during the rainy season. Thus, this work aims at selecting cowpea varieties that can be cultivated in times of drought without compromising their yields and yield components. Twenty cowpea varieties were used, including 17 improved cultivars and 3 landraces. The experiment was conducted at the International Institute of Tropical Agriculture in Benin and laid at a split-plot design with four replicates. Each genotype was exposed to three water treatments: fully irrigated control, vegetative stress (when plants were 23 days old, drought stress was imposed for 30 days), and reproductive stress (once the first flowers were observed, water stress was imposed for 30 days). The results showed that photochemical yield, chlorophyll content, and relative water content were reduced under water deficit at the vegetative and reproductive stages. But there were no significant differences in proline content among cowpea varieties. Agronomic traits such as number of days to flowering, number of pods, yield per plant, the weight of 100 seeds, and harvest time showed significant differences under water stress. Overall, the landraces and cultivars including Kpodjiguegue, KVX 61-1, and IT 06-K-242-3 were the most tolerant to drought stress at the vegetative and reproductive stages and could potentially be used in breeding programs to improve drought tolerance of cowpeas.

scholarly journals Effects of Water Stress and Modern Biostimulants on Growth and Quality Characteristics of Mint

Agronomy ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 6 ◽  
Author(s):  
Hosam O. Elansary ◽  
Eman A. Mahmoud ◽  
Diaa O. El-Ansary ◽  
Mohamed A. Mattar
Keyword(s):  
Water Stress ◽  
Antioxidant Activities ◽  
Dry Weight ◽  
Water Levels ◽  
Irrigation Water Use Efficiency ◽  
Irrigation Water Use ◽  
Relative Water ◽  
Use Efficiency ◽  
Pharmaceutical Industries ◽  
Medicinal Properties

Natural biostimulants combine different elicitors that may influence economic properties of herbal crops, such as mint. Mint (Mentha longifolia L.) plants were subjected to three water levels based on container substrate capacity (CSC; 100% CSC, 70% CSC, and 50% CSC) and/or applications of four biostimulants (CRADLE™, Mobilizer™, Nanozim De’Lite™ [ND], and Nanozim NXT™ [NN]). ND and NN exhibited higher vegetative growth and root dry weight than the control (without biostimulants) and other treatments. NN produced the highest fresh and dry mint yields under all water levels. Irrigation water-use efficiency (IWUE) of NN was highest (2.78 kg m−3) with 70% CSC, whereas the control produced the lowest IWUE (1.85 kg m−3) with 100% CSC. Biostimulants boosted physiological and metabolic responses, including gas exchange, leaf water potential, relative water content, and proline accumulation of stressed plants. NN treatment with 70% CSC had the highest essential oil (EO) ratio (3.35%). Under 70% and 50% CSC with NN treatment, the proportion of 1,8-cineol increased and that of pulegone decreased in EOs. Increased antioxidant activities, reduced H2O2 levels, and increased catalase and superoxide dismutase activities were observed. Applications of ND and NN during water stress conditions increased economic and medicinal properties of mint EOs with applications in the agricultural and pharmaceutical industries.

Responses of young plants of Vachellia farnesiana to drought

2020 ◽  
Vol 68 (8) ◽  
pp. 587 ◽  
Author(s):  
Josiane Moura ◽  
Evandro A. Vieira
Keyword(s):  
Water Deficit ◽  
Field Capacity ◽  
Carotenoid Content ◽  
Simultaneous Increase ◽  
Growth Responses ◽  
Chlorophylls A And B ◽  
Relative Water ◽  
Phosphorus And Potassium ◽  
Environment Experiment ◽  
Physiological And Biochemical

Water availability in soil modulates plant acclimatisation responses in different habitats. In this study, we evaluated the effect of water deficit on the physiological, biochemical and growth responses of Vachellia farnesiana. Open environment experiment was conducted during 90 days and two conditions of hydration were tested: full hydration (H) and water deficit (WD) at 25% of field capacity. The relative water content (RWC) of the leaves under WD showed a 30.2% decrease (P &lt; 0.01), compared with the hydrated plants at 30 days. A decrease in the RWC led to decrease in the osmotic potential (Ψs), quantum yield of PSII (Fv/Fm) and lesser content of chlorophylls a and b under WD. A greater carotenoid content and simultaneous increase in the content of proline, H2O2 and phenolic compounds of the leaves was also observed in WD. Water deficit also promoted differences in the nitrogen, phosphorus, and potassium content of the leaves when compared with hydrated plants. Although they showed growth deficit, plants of V. farnesiana demonstrated resistance to WD through physiological and biochemical adjustments.

Sign in / Sign up

Export Citation Format

Share Document