Chickpea plant responses to polyphosphate fertiliser forms and drip fertigation frequencies: effect on photosynthetic performance and phenotypic traits

Plant responses to abiotic stresses are complex and dynamic, and involve changes in different traits, either as the direct consequence of the stress, or as an active acclimatory response. Abiotic stresses frequently occur simultaneously or in succession, rather than in isolation. Despite this, most studies have focused on a single stress and single or few plant traits. To address this gap, our study comprehensively and categorically quantified the individual and combined effects of three major abiotic stresses associated with climate change (flooding, progressive drought and high temperature) on 12 phenotypic traits related to morphology, development, growth and fitness, at different developmental stages in four Arabidopsis thaliana accessions. Combined sub-lethal stresses were applied either simultaneously (high temperature and drought) or sequentially (flooding followed by drought). In total, we analyzed the phenotypic responses of 1782 individuals across these stresses and different developmental stages. Overall, abiotic stresses and their combinations resulted in distinct patterns of effects across the traits analyzed, with both quantitative and qualitative differences across accessions. Stress combinations had additive effects on some traits, whereas clear positive and negative interactions were observed for other traits: 9 out of 12 traits for high temperature and drought, 6 out of 12 traits for post-submergence and drought showed significant interactions. In many cases where the stresses interacted, the strength of interactions varied across accessions. Hence, our results indicated a general pattern of response in most phenotypic traits to the different stresses and stress combinations, but it also indicated a natural genetic variation in the strength of these responses. Overall, our study provides a rich characterization of trait responses of Arabidopsis plants to sub-lethal abiotic stresses at the phenotypic level and can serve as starting point for further in-depth physiological research and plant modelling efforts.

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The Roles of Cytokinins in Plants and Their Response to Environmental Stimuli

Plants ◽

10.3390/plants9091158 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1158

Author(s):

R. J. Neil Emery ◽

Anna Kisiala

Keyword(s):

Plant Growth ◽

Pathogenic Bacteria ◽

Signaling Molecules ◽

Photosynthetic Performance ◽

Plant Responses ◽

Plant Metabolism ◽

Plant Interactions ◽

Environmental Stimuli ◽

Open Questions ◽

Almost All

Cytokinins (CKs) are adenine-derived, small-molecule plant growth regulators that control aspects of almost all plant growth and development processes. Internally, CKs play significant roles in plant cell division, nutrient allocation, and photosynthetic performance, and they are also detection and signaling agents for plant responses to the environmental challenges. CK functions in plant metabolism include plant adaptations to various abiotic stresses as well as their regulatory role in plant interactions with biotic components of the environment. Interestingly, CK biosynthesis is not exclusive to plants. New genetic and chemical approaches have revealed that both beneficial (symbiotic microorganisms) and detrimental (pathogenic bacteria, fungi, or insects) non-plant biota can secrete these phytohormones to purposefully modify plant metabolism. Therefore, while many open questions remain about how CKs are actively utilized by plants and plant-interacting organisms, CK roles should be seen more broadly, as signaling molecules for which effects range from within cells to as far as interkingdom relationships. The papers in this Special Issue highlight several aspects of CK biosynthesis, metabolism, and functions within plants and among plant-associated organisms, typifying the extensive range of roles played by these signaling molecules. The collection of papers represents new examples for CK researchers to consider advancing the growing range of topics related to how CKs mediate responses to many kinds of environmental stimuli and stresses.

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Photosynthesis and Growth of Pennisetum centrasiaticum (C4) is Superior to Calamagrostis pseudophragmites (C3) during Drought and Recovery

Plants ◽

10.3390/plants9080991 ◽

2020 ◽

Vol 9 (8) ◽

pp. 991

Author(s):

Yayong Luo ◽

Xueyong Zhao ◽

Ginger R. H. Allington ◽

Lilong Wang ◽

Wenda Huang ◽

...

Keyword(s):

Drought Stress ◽

Water Status ◽

Regional Climate ◽

Co2 Assimilation ◽

Photosynthetic Performance ◽

Thermal Dissipation ◽

Plant Responses ◽

C4 Plant ◽

C3 Plant ◽

Ecosystem Level

Global warming and changes in rainfall patterns may put many ecosystems at risk of drought. These stressors could be particularly destructive in arid systems where species are already water-limited. Understanding plant responses in terms of photosynthesis and growth to drought and rewatering is essential for predicting ecosystem-level responses to climate change. Different drought responses of C3 and C4 species could have important ecological implications affecting interspecific competition and distribution of plant communities in the future. For this study, C4 plant Pennisetum centrasiaticum and C3 plant Calamagrostis pseudophragmites were subjected to progressive drought and subsequent rewatering in order to better understand their differential responses to regional climate changes. We tracked responses in gas exchange, chlorophyll fluorescence, biomass as well as soil water status in order to investigate the ecophysiological responses of these two plant functional types. Similar patterns of photosynthetic regulations were observed during drought and rewatering for both psammophytes. They experienced stomatal restriction and nonstomatal restriction successively during drought. Photosynthetic performance recovered to the levels in well-watered plants after rewatering for 6–8 days. The C4 plant, P. centrasiaticum, exhibited the classic CO2-concentrating mechanism and more efficient thermal dissipation in the leaves, which confers more efficient CO2 assimilation and water use efficiency, alleviating drought stress, maintaining their photosynthetic advantage until water deficits became severe and quicker recovery after rewatering. In addition, P. centrasiaticum can allocate a greater proportion of root biomass in case of adequate water supply and a greater proportion of above-ground biomass in case of drought stress. This physiological adaptability and morphological adjustment underline the capacity of C4 plant P. centrasiaticum to withstand drought more efficiently and recover upon rewatering more quickly than C. pseudophragmites and dominate in the Horqin Sandy Land.

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The use of high throughput phenotyping for assessment of heat stress-induced changes in Arabidopsis

10.1101/838102 ◽

2019 ◽

Cited By ~ 1

Author(s):

Ge Gao ◽

Mark A. Tester ◽

Magdalena M. Julkowska

Keyword(s):

Heat Stress ◽

Quantum Yield ◽

Recovery Period ◽

Plant Morphology ◽

Photosynthetic Performance ◽

Photochemical Quenching ◽

Leaf Angle ◽

Plant Responses ◽

The Difference ◽

Size And Morphology

AbstractThe worldwide rise in heatwave frequency poses a threat to plant survival and productivity. Determining the new marker phenotypes that show reproducible response to heat stress and contribute to heat stress tolerance is becoming a priority. In this study, we describe a protocol focusing on the daily changes in plant morphology and photosynthetic performance after exposure to heat stress using an automated non-invasive phenotyping system. Heat stress exposure resulted in an acute reduction of quantum yield of photosystem II and increased leaf angle. In the longer term, exposure to heat also affected plant growth and morphology. By tracking the recovery period of WT and mutants impaired in thermotolerance (hsp101), we observed that the difference in maximum quantum yield, quenching, rosette size, and morphology. By examining the correlation across the traits throughout time, we observed that early changes in photochemical quenching corresponded with the rosette size at later stages, which suggests the contribution of quenching to overall heat tolerance. We also determined that 6h of heat stress provides the most informative insight in plant responses to heat, as it shows a clear separation between treated and non-treated plants as well as WT and hsp101. Our work streamlines future discoveries by providing an experimental protocol, data analysis pipeline and new phenotypes that could be used as targets in thermotolerance screenings.

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HSFA1 proteins mediate heat-induced accumulation of CPT7-derived polyprenols affecting thylakoid organization

10.1101/2021.12.22.473876 ◽

2021 ◽

Author(s):

Daniel Buszewicz ◽

Łucja Maria Kowalewska ◽

Radosław Mazur ◽

Marta Zajbt-Łuczniewska ◽

Liliana Surmacz ◽

...

Keyword(s):

Chloroplast Ultrastructure ◽

Photosynthetic Performance ◽

Photochemical Quenching ◽

Plant Responses ◽

Expression Change ◽

Heat Stress Response ◽

Heat Shock Transcription Factors ◽

Master Regulators ◽

Non Photochemical Quenching ◽

Induced Changes

Polyprenols are ubiquitous isoprenoid compounds that accumulate in large quantities in plant photosynthetic tissues. While our knowledge of polyprenol biochemistry is constantly expanding, the regulation of their biosynthesis as well as the molecular basis of their cellular action are still poorly understood. In Arabidopsis, the polyprenols Pren-9, -10 and -11, synthesized by cis-prenyltransferase 7 (CPT7), are localized in plastidial membranes and affect the photosynthetic performance of chloroplasts. In this report we present evidence that plastidial polyprenols are among the major constituents of thylakoid membranes. Disturbances in polyprenol level, caused by alterations in CPT7 expression, change chloroplast ultrastructure, affect aggregation of LHCII complexes and modulate non-photochemical quenching (NPQ). Moreover, we show that Arabidopsis responds to high temperature by upregulating expression of CPT7 and increasing the accumulation of CPT7-derived polyprenols. These heat-induced changes in polyprenol biosynthesis are mediated by Heat Shock Transcription Factors of the HSFA1 family, the master regulators of heat stress response. Collectively, results presented in this report bring us closer to understanding the mechanisms by which polyprenols affect plant physiology and provide an additional link between chloroplast biology and plant responses to changing environmental conditions.

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Synergistic Effects of Melatonin and Gamma-Aminobutyric Acid on Protection of Photosynthesis System in Response to Multiple Abiotic Stressors

Cells ◽

10.3390/cells10071631 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1631

Author(s):

Aida Shomali ◽

Sasan Aliniaeifard ◽

Fardad Didaran ◽

Mahmoud Lotfi ◽

Mohammad Mohammadian ◽

...

Keyword(s):

Vicia Faba ◽

Synergistic Effects ◽

Photosynthetic Performance ◽

Aminobutyric Acid ◽

Photochemical Quenching ◽

Plant Responses ◽

Total Biomass ◽

Gamma Aminobutyric Acid ◽

Ps Ii ◽

Abiotic Stressors

GABA (gamma-aminobutyric acid) and melatonin are endogenous compounds that enhance plant responses to abiotic stresses. The response of Vicia faba to different stressors (salinity (NaCl), poly ethylene glycol (PEG), and sulfur dioxide (SO2)) was studied after priming with sole application of GABA and melatonin or their co-application (GABA + melatonin). Both melatonin and GABA and their co-application increased leaf area, number of flowers, shoot dry and fresh weight, and total biomass. Plants treated with GABA, melatonin, and GABA + melatonin developed larger stomata with wider aperture compared to the stomata of control plants. The functionality of the photosynthetic system was improved in primed plants. To investigate the photosynthetic functionality in details, the leaf samples of primed plants were exposed to different stressors, including SO2, PEG, and NaCl. The maximum quantum yield of photosystem II (PS II) was higher in the leaf samples of primed plants, while the non-photochemical quenching (NPQ) of primed plants was decreased when leaf samples were exposed to the stressors. Correlation analysis showed the association of initial PIabs with post-stress FV/FM and NPQ. Stressors attenuated the association of initial PIabs with both FV/FM and NPQ, while priming plants with GABA, melatonin, or GABA + melatonin minimized the effect of stressors by attenuating these correlations. In conclusion, priming plants with both GABA and melatonin improved growth and photosynthetic performance of Vicia faba and mitigated the effects of abiotic stressors on the photosynthetic performance.

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Abstract #789: Type 2 Diabetes-Related Intermediate Phenotypic Traits in North Indian Patients with Diabetes

Endocrine Practice ◽

10.1016/s1530-891x(20)43647-x ◽

2005 ◽

Vol 11 ◽

pp. 16

Author(s):

Sandeep Kumar Mathur ◽

Piyush Chandra ◽

Sandhya Mishra ◽

Piyush Ajmera ◽

Praveen Sharma

Keyword(s):

Type 2 Diabetes ◽

Phenotypic Traits ◽

Indian Patients ◽

Patients With Diabetes

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Temporal dynamics of mycorrhizal fungal communities and co-associations with grassland plant communities following experimental manipulation of rainfall

10.32942/osf.io/t82ug ◽

2019 ◽

Cited By ~ 1

Author(s):

Coline Deveautour ◽

Sally Power ◽

Kirk Barnett ◽

Raul Ochoa-Hueso ◽

Suzanne Donn ◽

...

Keyword(s):

Community Composition ◽

Plant Community ◽

Plant Communities ◽

Fungal Community ◽

Mycorrhizal Fungi ◽

Temporal Dynamics ◽

Arbuscular Mycorrhizal ◽

Fungal Communities ◽

Plant Responses ◽

Rainfall Regimes

Climate models project overall a reduction in rainfall amounts and shifts in the timing of rainfall events in mid-latitudes and sub-tropical dry regions, which threatens the productivity and diversity of grasslands. Arbuscular mycorrhizal fungi may help plants to cope with expected changes but may also be impacted by changing rainfall, either via the direct effects of low soil moisture on survival and function or indirectly via changes in the plant community. In an Australian mesic grassland (former pasture) system, we characterised plant and arbuscular mycorrhizal (AM) fungal communities every six months for nearly four years to two altered rainfall regimes: i) ambient, ii) rainfall reduced by 50% relative to ambient over the entire year and iii) total summer rainfall exclusion. Using Illumina sequencing, we assessed the response of AM fungal communities sampled from contrasting rainfall treatments and evaluated whether variation in AM fungal communities was associated with variation in plant community richness and composition. We found that rainfall reduction influenced the fungal communities, with the nature of the response depending on the type of manipulation, but that consistent results were only observed after more than two years of rainfall manipulation. We observed significant co-associations between plant and AM fungal communities on multiple dates. Predictive co-correspondence analyses indicated more support for the hypothesis that fungal community composition influenced plant community composition than vice versa. However, we found no evidence that altered rainfall regimes were leading to distinct co-associations between plants and AM fungi. Overall, our results provide evidence that grassland plant communities are intricately tied to variation in AM fungal communities. However, in this system, plant responses to climate change may not be directly related to impacts of altered rainfall regimes on AM fungal communities. Our study shows that AM fungal communities respond to changes in rainfall but that this effect was not immediate. The AM fungal community may influence the composition of the plant community. However, our results suggest that plant responses to altered rainfall regimes at our site may not be resulting via changes in the AM fungal communities.

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