Response of the photosynthetic apparatus to a flowering-inductive period by water stress in Citrus

Climate change, food shortage, water scarcity, and population growth are some of the threatening challenges being faced in today’s world. Drought stress (DS) poses a constant challenge for agricultural crops and has been considered a severe constraint for global agricultural productivity; its intensity and severity are predicted to increase in the near future. Legumes demonstrate high sensitivity to DS, especially at vegetative and reproductive stages. They are mostly grown in the dry areas and are moderately drought tolerant, but severe DS leads to remarkable production losses. The most prominent effects of DS are reduced germination, stunted growth, serious damage to the photosynthetic apparatus, decrease in net photosynthesis, and a reduction in nutrient uptake. To curb the catastrophic effect of DS in legumes, it is imperative to understand its effects, mechanisms, and the agronomic and genetic basis of drought for sustainable management. This review highlights the impact of DS on legumes, mechanisms, and proposes appropriate management approaches to alleviate the severity of water stress. In our discussion, we outline the influence of water stress on physiological aspects (such as germination, photosynthesis, water and nutrient uptake), growth parameters and yield. Additionally, mechanisms, various management strategies, for instance, agronomic practices (planting time and geometry, nutrient management), plant growth-promoting Rhizobacteria and arbuscular mycorrhizal fungal inoculation, quantitative trait loci (QTLs), functional genomics and advanced strategies (CRISPR-Cas9) are also critically discussed. We propose that the integration of several approaches such as agronomic and biotechnological strategies as well as advanced genome editing tools is needed to develop drought-tolerant legume cultivars.

Download Full-text

Plastid Signals Confer Arabidopsis Tolerance to Water Stress

Zeitschrift für Naturforschung C ◽

10.1515/znc-2011-1-207 ◽

2011 ◽

Vol 66 (1-2) ◽

pp. 47-54 ◽

Cited By ~ 3

Author(s):

Jian Cheng ◽

Chun-Xia He ◽

Zhong-Wei Zhang ◽

Fei Xu ◽

Da-Wei Zhang ◽

...

Keyword(s):

Water Stress ◽

Photosynthetic Apparatus ◽

Nuclear Gene ◽

Stress Adaptation ◽

Wild Type ◽

Oxidative Damages ◽

Nuclear Gene Expression ◽

Retrograde Signalling ◽

The Relationship ◽

Mutant Cells

Plastid-to-nucleus retrograde signalling coordinates nuclear gene expression with chloroplast function and is essential for the photoautotrophic life-style of plants. The relationship between plastid signalling and water stress response was investigated with genome uncoupled (gun) mutants, gun1, gun3, and gun5, and an abscisic acid (ABA)-responsible transcription factor mutant, abi4. The results showed that gun1, gun3, gun5, and abi4 mutants suffered from more oxidative damages than the wild-type plants under the water stress and the water stress + herbicide (norflurazon, NF) co-treatment. Superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX) activities could not be prompted in the plastidsignalling defective mutants under the stress conditions. At the same time, Lhcb expression was not repressed in the plastid-signalling defective mutants by the NF treatment or water stress. Therefore, the photosynthetic apparatus in the mutant cells could not be closed during the stresses and the excessive light caused more photodamages on the mutant leaves. The roles of GUN1, GUN3, GUN5 and ABI4 proteins in environmental stress adaptation have been discussed.

Download Full-text

Water use efficiency, growth and anatomic-physiological parameters of Mediterranean xerophytes as affected by substrate and irrigation on a green roof

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha49212283 ◽

2021 ◽

Vol 49 (2) ◽

pp. 12283

Author(s):

Lamprini TASSOULA ◽

Maria PAPAFOTIOU ◽

Georgios LIAKOPOULOS ◽

George KARGAS

Keyword(s):

Water Stress ◽

Water Use Efficiency ◽

Water Use ◽

Green Roof ◽

Photosynthetic Apparatus ◽

Green Roofs ◽

Physiological Parameters ◽

Irreversible Damage ◽

Grape Marc ◽

Use Efficiency

The water use efficiency, growth and anatomic-physiological parameters of Mediterranean medicinal xerophytes on a green roof was investigated, under the effect of water stress and different types of substrate. Rooted cuttings of Convolvulus cneorum, Origanum dictamnus, Sideritis athoa, Atriplex halimus and Lomelosia cretica were planted on a roof in Athens, Greece. Two substrate types, 10 cm deep, were used, i.e. grape marc compost: perlite: soil: pumice (3:3:2:2, v/v) and a lighter one, i.e. grape marc compost: perlite: pumice (3:3:4, v/v). Two irrigation frequencies were applied during the dry period (summer), normal and sparse, when substrate moisture was 17-20% and 5-11%, respectively. Water use efficiency was increased by sparse irrigation in A. halimus and L. cretica and by soil substrate in C. cneorum. Sparse irrigation reduced dry weight in O. dictamnus, S. athoa and L. cretica and in A. halimus in combination with soilless substrate. It increased leaf thickness in all species and reduced Chlολ in all species, other than S. athoa, while in C. cneorum, O. dictamnus and L. cretica this was evident only in the presence of soil in the substrate. In summer, one d before irrigation, stomatal resistance (Rleaf) was increased and maximum quantum yield of PSII (ΦPSIIο) decreased indicating water limitation, while both parameters were restored to normal levels one d after irrigation indicating that both can serve as sensitive indicators of the onset of water stress. ΦPSIIο values, never fell to critical levels, excluding irreversible damage to the photosynthetic apparatus. Therefore, all five plant species are recommended for use on extensive green roofs in semi-arid areas.

Download Full-text

Effects of Whole-root and Half-root Water Stress on Gas Exchange and Chlorophyll Fluorescence Parameters in Apple Trees

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.138.5.395 ◽

2013 ◽

Vol 138 (5) ◽

pp. 395-402 ◽

Cited By ~ 6

Author(s):

Jinhong Yuan ◽

Man Xu ◽

Wei Duan ◽

Peige Fan ◽

Shaohua Li

Keyword(s):

Chlorophyll Fluorescence ◽

Water Stress ◽

Root Zone ◽

Photosynthetic Apparatus ◽

Fruit Trees ◽

Stomatal Limitation ◽

Apple Trees ◽

Chlorophyll Fluorescence Parameters ◽

Acceptor Side ◽

Polyethylene Glycol 6000

The responses of photosynthesis, chlorophyll fluorescence, and de-epoxidation state of the xanthophyll cycle pigments (DEPS) of micropropagated apple trees (Malus ×domestica) were investigated under whole-root water stress (WRS) and half-root water stress (HRS) induced by polyethylene glycol 6000 to simulate whole and partial root zone drying. Compared with control plants without water stress, plants under WRS and HRS exhibited reduced leaf net photosynthetic rate (Pn) and stomatal conductance (gS) with a greater reduction in WRS than in HRS plants. However, intercellular CO2 concentration (Ci) increased under WRS as water stress was prolonged, signifying a non-stomatal limitation of Pn. Regarding HRS, decreased Pn was mainly the result of a stomatal limitation explained by a relatively low Ci. Changes in photosynthesis and chlorophyll parameters indicate that severe and slight damage occurred to the photosynthetic apparatus of WRS and HRS leaves, respectively, starting at Day 3 after initiating water stress. This damage was not evident on the donor side but was expressed as a reduced capacity of the acceptor side of the photosystem II reaction centers. To prevent damage from excess light, the DEPS of WRS leaf increased. Decreased gS could explain reduced water use under an irrigation strategy of partial root zone drying in fruit trees.

Download Full-text

Effects of Water Stress and High-Temperature Stress on the Structure and Activity of Photosynthetic Apparatus of Zea Mays and Helianthus Annuus

Photosynthetica ◽

10.1023/a:1010961218145 ◽

2000 ◽

Vol 38 (3) ◽

pp. 361-366 ◽

Cited By ~ 54

Author(s):

I. Dekov ◽

T. Tsonev ◽

I. Yordanov

Keyword(s):

Zea Mays ◽

High Temperature ◽

Water Stress ◽

Helianthus Annuus ◽

Temperature Stress ◽

Photosynthetic Apparatus ◽

High Temperature Stress ◽

Structure And Activity

Download Full-text

Effect of water stress on the photosynthetic apparatus of plants and the protective role of cytokinins: A review

Applied Biochemistry and Microbiology ◽

10.1007/s10438-005-0021-9 ◽

2005 ◽

Vol 41 (2) ◽

pp. 115-128 ◽

Cited By ~ 24

Author(s):

I. I. Chernyad?ev

Keyword(s):

Water Stress ◽

Photosynthetic Apparatus ◽

Protective Role ◽

Effect Of Water

Download Full-text

Exogenous Isoprene Confers Physiological Benefits in a Negligible Isoprene Emitter (Acer monspessulanum L.) under Water Deficit

Plants ◽

10.3390/plants9020159 ◽

2020 ◽

Vol 9 (2) ◽

pp. 159 ◽

Cited By ~ 1

Author(s):

Elena Ormeño ◽

Justine Viros ◽

Jean-Philippe Mévy ◽

Alain Tonetto ◽

Amélie Saunier ◽

...

Keyword(s):

Water Stress ◽

Water Deficit ◽

Plant Protection ◽

Photosynthetic Apparatus ◽

Net Photosynthesis ◽

Ambient Air ◽

High Concentration ◽

Protection Mechanism ◽

Severe Water Stress ◽

Physiological Benefits

Isoprene, the main volatile released by plants, is known to protect the photosynthetic apparatus in isoprene emitters submitted to oxidative pressures caused by environmental constraints. Whether ambient isoprene contributes to protect negligible plant emitters under abiotic stress conditions is less clear, and no study has tested if ambient isoprene is beneficial during drought periods in plant species that naturally release negligible isoprene emissions. This study examines the effect of exogenous isoprene (20 ppbv) on net photosynthesis, stomatal conductance and production of H2O2 (a reactive oxygen species: ROS) in leaves of Acer monspessulanum (a negligible isoprene emitter) submitted to three watering treatments (optimal, moderate water stress and severe water stress). Results showed that A. monspessulanum exhibited a net photosynthesis increase (+30%) and a relative leaf H2O2 decrease when saplings were exposed to an enriched isoprene atmosphere compared to isoprene-free conditions under moderate water deficit. Such physiological improvement under isoprene exposure was not observed under optimal watering or severe water stress. These findings suggest that when negligible isoprene emitters are surrounded by a very high concentration of isoprene in the ambient air, some plant protection mechanism occurs under moderate water deficit probably related to protection against ROS damage eventually impeding photosynthesis drop.

Download Full-text