Cold acclimation and vernalization represent the major evolutionary adaptive responses to ensure winter survival of temperate plants. Due to climate change, mild winters can paradoxically worsen plant winter survival due to cold deacclimation induced by warm periods during winter. It seems that the ability of cold reacclimation in overwintering Triticeae cereals is limited, especially in vernalized plants. In the present review, the major factors determining cold acclimation (CA), deacclimation (DA) and reacclimation (RA) processes in winter-type Triticeae, namely wheat and barley, are discussed. Recent knowledge on cold sensing and signaling is briefly summarized. The impacts of chilling temperatures, photoperiod and light spectrum quality as the major environmental factors, and the roles of soluble proteins and sugars (carbohydrates) as well as cold stress memory molecular mechanisms as the major plant-based factors determining CA, DA, and RA processes are discussed. The roles of plant stress memory mechanisms and development processes, namely vernalization, in winter Triticeae reacclimation are elucidated. Recent findings about the role of O-glucose N-acetylation of target proteins during vernalization and their impacts on the expression of VRN1 gene and other target proteins resulting in cold-responsive modules reprogramming are presented.
- Klíčová slova
- Cold acclimation, Deacclimation, Light quality, Photoperiod, Reacclimation, Triticeae, Vernalization,
- MeSH
- aklimatizace * fyziologie MeSH
- ječmen (rod) * fyziologie metabolismus MeSH
- nízká teplota * MeSH
- pšenice * fyziologie metabolismus MeSH
- roční období * MeSH
- rostlinné proteiny metabolismus genetika MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- rostlinné proteiny MeSH
Alternating electric current and alternating electromagnetic fields revolutionized physics and engineering and led to many technologies that shape modern life. Despite these undisputable achievements that have been reached using stimulation by harmonic oscillations over centuries, applications in biology remain rare. Photosynthesis research is uniquely suited to unleash this potential because light can be modulated as a harmonic function, here sinus. Understanding the response of photosynthetic organisms to sinusoidal light is hindered by the complexity of dynamics that such light elicits, and by the mathematical apparatus required for understanding the signals in the frequency domain which, although well-established and simple, is outside typical curricula in biology. Here, we approach these challenges by presenting a mathematical model that was designed specifically to simulate the response of photosynthetic light reactions to light which oscillates with periods that often occur in nature. The independent variables of the model are the plastoquinone pool, the photosystem I donors, lumen pH, ATP, and the chlorophyll fluorescence (ChlF) quencher that is responsible for the qE non-photochemical quenching. Dynamics of ChlF emission, rate of oxygen evolution, and non-photochemical quenching are approximated by dependent model variables. The model is used to explain the essentials of the frequency-domain approaches up to the level of presenting Bode plots of frequency-dependence of ChlF. The model simulations were found satisfactory when compared with the Bode plots of ChlF response of the green alga Chlamydomonas reinhardtii to light that was oscillating with a small amplitude and frequencies between 7.8 mHz and 64 Hz.
- Klíčová slova
- Chlorophyll fluorescence, Fourier analysis, Frequency domain, Harmonic light, Non-photochemical quenching, Oxygen evolution, Plastoquinone pool,
- MeSH
- biologické modely MeSH
- Chlamydomonas reinhardtii fyziologie účinky záření MeSH
- chlorofyl metabolismus MeSH
- fotosyntéza * fyziologie účinky záření MeSH
- fotosystém I (proteinový komplex) metabolismus MeSH
- světlo * MeSH
- teoretické modely MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- chlorofyl MeSH
- fotosystém I (proteinový komplex) MeSH
Actin cytoskeleton and reactive oxygen species are principal determinants of root hair polarity and tip growth. Loss of function in RESPIRATORY BURST OXIDASE HOMOLOG C/ROOT HAIR DEFECTIVE 2 (AtRBOHC/RHD2), an NADPH oxidase emitting superoxide to the apoplast, and in ACTIN 2, a vegetative actin isovariant, in rhd2-1 and der1-3 mutants, respectively, lead to similar defects in root hair formation and elongation Since early endosome-mediated polar localization of AtRBOHC/RHD2 depends on actin cytoskeleton, comparing the proteome-wide consequences of both mutations might be of eminent interest. Therefore, we employed a differential proteomic analysis of Arabidopsis rhd2-1 and der1-3 mutants. Both mutants exhibited substantial alterations in abundances of stress-related proteins. Notably, plasma membrane (PM)-localized PIP aquaporins showed contrasting abundance patterns in the mutants compared to wild-types. Drought-responsive proteins were mostly downregulated in rhd2-1 but upregulated in der1-3. Proteomic data suggest that opposite to der1-3, altered vesicular transport in rhd2-1 mutant likely contributes to the deregulation of PM-localized proteins, including PIPs. Moreover, lattice light sheet microscopy revealed reduced actin dynamics in rhd2-1 roots, a finding contrasting with previous reports on der1-3 mutant. Phenotypic experiments demonstrated a drought stress susceptibility in rhd2-1 and resistance in der1-3. Thus, mutations in AtRBOHC/RHD2 and ACTIN2 cause similar root hair defects, but they differently affect the actin cytoskeleton and vesicular transport. Reduced actin dynamics in rhd2-1 mutant is accompanied by alteration of vesicular transport proteins abundance, likely leading to altered protein delivery to PM, including aquaporins, thereby significantly affecting drought stress responses.
- Klíčová slova
- ACTIN2, Aquaporin, Arabidopsis, Drought stress, NADPH oxidase, PIP1, Plasma membrane, Proteomics, RBOHC, actin,
- MeSH
- akvaporiny * metabolismus genetika MeSH
- Arabidopsis * genetika metabolismus MeSH
- buněčná membrána * metabolismus MeSH
- kořeny rostlin * metabolismus genetika MeSH
- mikrofilamenta * metabolismus MeSH
- mutace MeSH
- období sucha * MeSH
- proteiny huseníčku * metabolismus genetika MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- akvaporiny * MeSH
- proteiny huseníčku * MeSH
Applying biochar has beneficial effects on regulating plant growth by providing water and nutrient availability for plants due to its physicochemical characteristics. Nevertheless, it is still unclear how soil and biochar interactions strengthen crop lodging resistance. The objective of the current study was to find out how soil physicochemical conditions and alterations in biochar affect lodging resistance and crop productivity in cereals. To do this, a meta-analysis was carried out using nine groups of effective variables including type of feedstock, pyrolysis temperature, application rate, soil pH, total nitrogen, available phosphorus, potassium, organic matter (OM), and soil texture. Results showed that straw-derived biochar caused the highest positive effect size in the dry weight of biomass (20.5%) and grain yield (19.9%). Also, the lowest lodging index was observed from straw (-8.3%) and wood-based (-5.6%) biochars. Besides, the high application rate of biochar results in the highest positive effect sizes of plant cellulose (8.1%) and lignin content (7.6%). Soils that contain >20 g kg-1 OM, resulted in the highest positive effect size in dry biomass (27.9%), grain yield (30.2%), and plant height (4.7%). Also, fine-textured soil plays an important role in increasing polymers in the anatomical structure of plants. Overall, the strong connection between biochar and soil processes, particularly the availability of OM, could strengthen plants' ability to tolerate lodging stress and contribute to high nutrient efficiency in terms of crop output and cell wall thickening.
- Klíčová slova
- Biochar amendment, Crop resistance, Crop yield, Lodging index, Meta-analysis,
- MeSH
- biomasa MeSH
- dřevěné a živočišné uhlí * MeSH
- půda * chemie MeSH
- zemědělské plodiny * růst a vývoj metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- metaanalýza MeSH
- Názvy látek
- biochar MeSH Prohlížeč
- dřevěné a živočišné uhlí * MeSH
- půda * MeSH
Cytokinins are growth-regulating plant hormones that are considered to adjust plant development under environmental stresses. During sole ammonium nutrition, a condition known to induce growth retardation of plants, altered cytokinin content can contribute to the characteristic ammonium toxicity syndrome. To understand the metabolic changes in cytokinin pools, cytokinin biosynthesis and degradation were analyzed in the leaves and roots of mature Arabidopsis plants. We found that in leaves of ammonium-grown plants, despite induction of biosynthesis on the expression level, there was no active cytokinin build-up because they were effectively routed toward their downstream catabolites. In roots, cytokinin conjugation was also induced, together with low expression of major synthetic enzymes, resulting in a decreased content of the trans-zeatin form under ammonium conditions. Based on these results, we hypothesized that in leaves and roots, cytokinin turnover is the major regulator of the cytokinin pool and does not allow active cytokinins to accumulate. A potent negative-regulator of root development is trans-zeatin, therefore its low level in mature root tissues of ammonium-grown plants may be responsible for occurrence of a wide root system. Additionally, specific cytokinin enhancement in apical root tips may evoke a short root phenotype in plants under ammonium conditions. The ability to flexibly regulate cytokinin metabolism and distribution in root and shoot tissues can contribute to adjusting plant development in response to ammonium stress.
- Klíčová slova
- Active cytokinin bases, Ammonium nutrition, Cytokinin biosynthesis, Cytokinin conjugation, Cytokinin degradation, Plant growth suppression, Root development,
- MeSH
- amoniové sloučeniny * metabolismus MeSH
- Arabidopsis * metabolismus MeSH
- cytokininy * metabolismus biosyntéza MeSH
- kořeny rostlin * metabolismus MeSH
- listy rostlin * metabolismus MeSH
- regulace genové exprese u rostlin MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- amoniové sloučeniny * MeSH
- cytokininy * MeSH
The development of the mining industry and the overuse of inorganic fertilizers have led to an excess of manganese (Mn) in the soil, thereby, contaminating the soil environment and people's health. On heavy metal-contaminated soils, the combined arbuscular mycorrhizal fungi (AMF)-phytoremediation technique becomes a hotspot because of its environmentally friendly, in situ remediation. AMF inoculation often leads to a decrease in host Mn acquisition, which provides a basis for its application in phytoremediation of contaminated soils. Moreover, the utilization value of native AMF is greater than that of exotic AMF, because native AMF can adapt better to Mn-contaminated soils. In addition to the fact that AMF enhance plant Mn tolerance responses such as regionalization, organic matter chelation, limiting uptake and efflux, and so on, AMF also develop plant-independent fungal pathways such as direct biosorption of Mn by mycorrhizal hyphae, fungal Mn transporter genes, and sequestration of Mn by mycorrhizal hyphae, glomalin, and arbuscule-containing root cortical cells, which together mitigate excessive Mn toxicity to plants. Clarifying AMF-plant interactions under Mn stress will provide support for utilizing AMF as a phytoremediation in Mn-contaminated soils. The review reveals in detail how AMF develop its own mechanisms for responding to excess Mn and how AMF enhance plant Mn tolerance, accompanied by perspectives for future research.
- Klíčová slova
- Biosorption, Manganese transporter, Mycorrhiza, Regionalization, Sequestration,
- MeSH
- biodegradace * MeSH
- kořeny rostlin mikrobiologie metabolismus účinky léků MeSH
- látky znečišťující půdu toxicita metabolismus MeSH
- mangan * metabolismus toxicita MeSH
- mykorhiza * metabolismus fyziologie MeSH
- rostliny * metabolismus účinky léků mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- látky znečišťující půdu MeSH
- mangan * MeSH
In Arabidopsis, the plastidial isoform of phosphoglucose isomerase, PGI1, mediates growth and photosynthesis, likely due to its involvement in the vascular production of cytokinins (CK). To examine this hypothesis, we characterized pgi1-2 knockout plants impaired in PGI1 and pgi1-2 plants specifically expressing PGI1 in root tips and vascular tissues. Moreover, to investigate whether the phenotype of pgi1-2 plants is due to impairments in the plastidial oxidative pentose phosphate pathway (OPPP) or the glycolytic pathway, we characterized pgl3-1 plants with reduced OPPP and pfk4pfk5 knockout plants impaired in plastidial glycolysis. Compared with wild-type (WT) leaves, pgi1-2 leaves exhibited weaker expression of photosynthesis- and 2-C-methyl-D-erythritol 4-P (MEP) pathway-related proteins, and stronger expression of oxidative stress protection-related enzymes. Consistently, pgi1-2 leaves accumulated lower levels of chlorophyll, and higher levels of tocopherols, flavonols and anthocyanins than the WT. Vascular- and root tip-specific PGI1 expression countered the reduced photosynthesis, low MEP pathway-derived CK content, dwarf phenotype and the metabolic characteristics of pgi1-2 plants, reverting them to WT-like levels. Moreover, pgl3-1, but not pfk4pfk5 plants phenocopied pgi1-2. Histochemical analyses of plants expressing GUS under the control of promoter regions of genes encoding plastidial OPPP enzymes exhibited strong GUS activity in root tips and vascular tissues. Overall, our findings show that root tip and vascular PGI1-mediated plastidial OPPP activity affects photosynthesis and growth through mechanisms involving long-distance modulation of the leaf proteome by MEP pathway-derived CKs.
- Klíčová slova
- Cytokinin, MEP pathway, Oxidative pentose phosphate pathway, Photosynthesis,
- MeSH
- anthokyaniny metabolismus MeSH
- Arabidopsis * metabolismus MeSH
- cytokininy metabolismus MeSH
- fotosyntéza MeSH
- pentózofosfátový cyklus * MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- anthokyaniny MeSH
- cytokininy MeSH
This study investigated the effect of light intensity and signaling on the regulation of far-red (FR)-induced alteration in photosynthesis. The low (LL: 440 μmol m-2 s-1) and high (HL: 1135 μmol m-2 s-1) intensity of white light with or without FR (LLFR: 545 μmol m-2 s-1 including 115 μmol m-2 s-1; HLFR: 1254 μmol m-2 s-1 + 140 μmol m-2 s-1) was applied on the tomato cultivar (Solanum Lycopersicon cv. Moneymaker) and mutants of phytochrome A (phyA) and phytochrome B (phyB1, and phyB2). Both light intensity and FR affected plant morphological traits, leaf biomass, and flowering time. Irrespective of genotype, flowering was delayed by LLFR and accelerated by HLFR compared to the corresponding light intensity without FR. In LLFR, a reduced energy flux through the electron transfer chain along with a reduced energy dissipation per reaction center improved the maximum quantum yield of PSII, irrespective of genotype. HLFR increased net photosynthesis and gas exchange properties in a genotype-dependent manner. FR-dependent regulation of hormones was affected by light signaling. It appeared that PHYB affected the levels of abscisic acid and salicylic acid while PHYA took part in the regulation of CK in FR-exposed plants. Overall, light intensity and signaling of FR influenced plants' photosynthesis and growth by altering electron transport, gas exchange, and changes in the level of endogenous hormones.
- Klíčová slova
- Flowering time, Gas exchange, Phytochromes, Phytohormones, Salicylic acid, Signaling, Stomatal conductance,
- MeSH
- Arabidopsis * metabolismus MeSH
- fotosyntéza MeSH
- fytochrom A genetika metabolismus MeSH
- fytochrom B genetika MeSH
- hormony MeSH
- Solanum lycopersicum * genetika MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- fytochrom A MeSH
- fytochrom B MeSH
- hormony MeSH
Minimizing the impact of heat and drought on crop yields requires varieties with effective protective mechanisms. We tested the hypothesis that even a short-term high temperature amplifies the negative effects of reduced water availability on leaf gas-exchange, but can induce long-lasting improvement in plant water-use efficiency after the stress period. Accordingly, three common varieties of winter wheat (Triticum aestivum) were grown under field conditions. During the stem extension, the plants were exposed to distinct temperatures (daily maximum 26 vs. 38 °C), water availabilities (75% of field water capacity vs. permanent wilting point), and their combination for 14 days. All treatments reduced light-saturated rates of CO2 assimilation and transpiration, particularly when heat and drought were combined. Drought enhanced water-use efficiency (WUE) in all varieties (31.4-36.4%), but not at high temperatures (decrease by 17-52%). Intrinsic WUE (iWUE), determined from the stable carbon isotope composition of grains, was enhanced by 7.9-37% in all treatments and varieties; however, not all changes were significant. The combination of heat and drought tended to increase total protein content in grains but reduced spike productivity. Noticeably, the strongest decline in spike productivity was observed in Elan - the variety displaying the smallest enhancement of iWUE, while it was negligible in Pannonia which shows the most pronounced improvement of iWUE. We conclude that even several hot and dry days can improve iWUE for the rest of the vegetation season. This improvement, however, does not necessarily lead to increased crop productivity possibly due to physiological trade-offs.
- Klíčová slova
- (13)C isotope discrimination, Abiotic stress, Gas-exchange measurements, Water-use efficiency, Wheat grain,
- MeSH
- izotopy uhlíku MeSH
- jedlá semena metabolismus MeSH
- období sucha MeSH
- pšenice * metabolismus MeSH
- teplota MeSH
- voda * metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- izotopy uhlíku MeSH
- voda * MeSH
As an indolamine, melatonin (C13H16N2O2) performs essential roles in the regulation of plant growth and development and ameliorates the harmful effects of abiotic stresses. This study examined two types of melatonin application, pre-sowing (prMel) and application during growth (ptMel), in wheat (Triticum aestivum L.) seedlings exposed to four different doses (100, 200, 300, and 400 Gy) of radioactive cobalt (60Co) gamma rays as dry seeds to investigate their ameliorative effects on ionizing radiation (IR) stress. Peroxidase, catalase, superoxide dismutase, ascorbate peroxidase, glutathione reductase, mono- and dihydroxyperoxidase, and phenylalanine ammonia-lyase activities, and levels of lipid peroxidation, H2O2, and total glutathione (GSH), and phenolic acids (PHAs) in soluble free, ester, glycoside and ester-bound forms were examined in the seedlings. Both melatonin applications were found to increase lipid peroxidation, H2O2, and GSH contents previously reduced by gamma irradiation. The IR treatment-induced increases in enzyme activities were significantly reduced by melatonin applications. The study findings indicated that high doses of IR resulted in significant decreases in the activity and levels of the measured traits. The predominant PHAs in the tissues were vanillic, ferulic, and p-coumaric acids. In addition, ptMel application combined with IR stress lowered the total phenolic acid contents in the soluble forms while increasing those in the cell wall-bound form. In conclusion, the antioxidant system in the seedlings exposed to the different gamma ray doses was regulated by prMel and ptMel applications in such a manner as to alleviate IR stress-induced oxidatives damages in the wheat.
- Klíčová slova
- Antioxidants, Ionizing radiation, Melatonin, Phenolic acids, Triticum aestivum, Wheat,
- MeSH
- antioxidancia * metabolismus MeSH
- estery farmakologie MeSH
- glutathion metabolismus MeSH
- ionizující záření MeSH
- melatonin * farmakologie MeSH
- oxidační stres MeSH
- peroxid vodíku farmakologie MeSH
- pšenice MeSH
- semenáček metabolismus MeSH
- superoxiddismutasa metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antioxidancia * MeSH
- estery MeSH
- glutathion MeSH
- melatonin * MeSH
- peroxid vodíku MeSH
- superoxiddismutasa MeSH
