- S. Aliniaeifard (2)
- Dimitris Bouranis (1)
- Federica Cattonaro (1)
- Chiara Evangelistella (1)
- Francesco Fabbrini (1)
- Dimitrios Fanourakis (1)
- Andrea Firrincieli (1)
- Marcel Fuchs (1)
- Habtamu Gebraegziabher (1)
- Antoine Harfouche (1)
- Benita Hyldgaard (1)
- Joost J.B. Keurentjes (1)
- Wenqian Jiang (1)
- Oliver Körner (1)
- Zhijun Liu (1)
- Riccardo Ludovisi (1)
- Shuo Lv (1)
- Yanting Lv (1)
- Kai Lønne Nielsen (1)
- U. Meeteren Van (1)
- Uulke Meeteren Van (1)
- Michele Morgante (1)
- Carl-Otto Ottosen (1)
- Lixia Pan (1)
- Simone Scalabrin (1)
- Giuseppe Scarascia Mugnozza (1)
- Xiaoping She (1)
- Cecilia Stanghellini (1)
- Alessio Valentini (1)
- Guodong Wang (1)
- Jiajing Wang (1)
- Jinbin Wu (1)
- Chen Yan Li (1)
- Jingwei Yang (1)
- Nan Yang (1)
- Yonghong Zhang (1)
- Yutao Zhang (1)
Natural genetic variation in stomatal response can help to increase acclimation of plants to dried environments
Aliniaeifard, S. ; Meeteren, U. Van - \ 2018
In: International Symposium on the Role of Plant Genetic Resources in Reclaiming Lands and Environment Deteriorated by Human and Natural Actions / Gharaghani, A., Khosh-Khui, M., International Society for Horticultural Science (Acta Horticulturae ) - ISBN 9789462611863 - p. 71 - 76.
Arid environments - Drought - Genetic variation - Stomata - VPD
In the current century, global warming is becoming an alarming issue causing an increase in the area of barren lands. Arid and semi-arid regions are characterised with shortage of water in both under- and above-ground environments. Plants with high water use efficiency should be considered for cultivation in those regions. Water loss is needed for cooling plant and absorbing minerals, however, excessive water loss can result in wilting. Plants control the water loss through adjusting the volume of stomatal guard cells and fine tuning the movements of stomata. Fine tune-functioning of stomata can help the plants to cope with drought conditions. Vapour pressure difference (VPD) between stomatal cavity and surrounding environment determines the water status of the leaf. In the short term, stomata respond in a regular way to VPD. However, when plants are exposed for a long term to conditions triggering stomatal opening (such as low VPD, prolonged lighting duration and air pollutants), the behaviour of the stomata in response to drought stress changes and the stomata are incapable of suitable response to closing stimuli (stomatal malfunctioning). Finding the reasons for occurrence of stomatal malfunctioning can help us to improve plant acclimation to dried environments. Exploring genetic variation in stomatal response among naturally occurring populations is the first step to figure out the mechanism controlling stomatal movements in different environments.
The functional dependence of canopy conductance on water vapor pressure deficit revisited
Fuchs, Marcel ; Stanghellini, Cecilia - \ 2018
International Journal of Biometeorology (2018). - ISSN 0020-7128 - p. 1 - 10.
Air humidity - Coupling - Stomata - Transpiration
Current research seeking to relate between ambient water vapor deficit (D) and foliage conductance (gF) derives a canopy conductance (gW) from measured transpiration by inverting the coupled transpiration model to yield gW = m − n ln(D) where m and n are fitting parameters. In contrast, this paper demonstrates that the relation between coupled gW and D is gW = AP/D + B, where P is the barometric pressure, A is the radiative term, and B is the convective term coefficient of the Penman-Monteith equation. A and B are functions of gF and of meteorological parameters but are mathematically independent of D. Keeping A and B constant implies constancy of gF. With these premises, the derived gW is a hyperbolic function of D resembling the logarithmic expression, in contradiction with the pre-set constancy of gF. Calculations with random inputs that ensure independence between gF and D reproduce published experimental scatter plots that display a dependence between gW and D in contradiction with the premises. For this reason, the dependence of gW on D is a computational artifact unrelated to any real effect of ambient humidity on stomatal aperture and closure. Data collected in a maize field confirm the inadequacy of the logarithmic function to quantify the relation between canopy conductance and vapor pressure deficit.
Strigolactone-triggered stomatal closure requires hydrogen peroxide synthesis and nitric oxide production in an abscisic acid-independent manner
Lv, Shuo ; Zhang, Yonghong ; Li, Chen Yan ; Liu, Zhijun ; Yang, Nan ; Pan, Lixia ; Wu, Jinbin ; Wang, Jiajing ; Yang, Jingwei ; Lv, Yanting ; Zhang, Yutao ; Jiang, Wenqian ; She, Xiaoping ; Wang, Guodong - \ 2018
New Phytologist 217 (2018)1. - ISSN 0028-646X - p. 290 - 304.
Abscisic acid (ABA) - Arabidopsis thaliana - Hydrogen peroxide (HO) - Nitric oxide (NO) - Stomata - Strigolactone
Accumulating data indicate that strigolactones (SLs) are implicated in the response to environmental stress, implying a potential effect of SLs on stomatal response and thus stress acclimatization. In this study, we investigated the molecular mechanism underlying the effect of SLs on stomatal response and their interrelation with abscisic acid (ABA) signaling. The impact of SLs on the stomatal response was investigated by conducting SL-feeding experiments and by analyzing SL-related mutants. The involvement of endogenous ABA and ABA-signaling components in SL-mediated stomatal closure was physiologically evaluated using genetic mutants. Pharmacological and genetic approaches were employed to examine hydrogen peroxide (H2O2) and nitric oxide (NO) production. SL-related mutants exhibited larger stomatal apertures, while exogenous SLs were able to induce stomatal closure and rescue the more widely opening stomata of SL-deficient mutants. The SL-biosynthetic genes were induced by abiotic stress in shoot tissues. Disruption of ABA-biosynthetic genes, as well as genes that function in guard cell ABA signaling, resulted in no impairment in SL-mediated stomatal response. However, disruption of MORE AXILLARY GROWTH2 (MAX2), DWARF14 (D14), and the anion channel gene SLOW ANION CHANNEL-ASSOCIATED 1 (SLAC1) impaired SL-triggered stomatal closure. SLs stimulated a marked increase in H2O2 and NO contents, which is required for stomatal closure. Our results suggest that SLs play a prominent role, together with H2O2/NO production and SLAC1 activation, in inducing stomatal closure in an ABA-independent mechanism.
Differential effects of elevated air humidity on stomatal closing ability of Kalanchoë blossfeldiana between the C3 and CAM states
Fanourakis, Dimitrios ; Hyldgaard, Benita ; Gebraegziabher, Habtamu ; Bouranis, Dimitris ; Körner, Oliver ; Nielsen, Kai Lønne ; Ottosen, Carl-Otto - \ 2017
Environmental and Experimental Botany 143 (2017). - ISSN 0098-8472 - p. 115 - 124.
Air humidity - Evaporative demand - Facultative CAM species - Stomata - Stomatal conductance - Transpiration
High relative air humidity (RH ≥ 85%) impairs stomatal functionality, attenuating plant capacity to cope with abiotic stress. Previous studies were limited to C3 species, so the RH effect on stomatal physiology of CAM plants remains unexplored. We addressed the topic through comparisons of C3 and CAM states in a facultative CAM species. These states were validated by diel measurements of net assimilation rate and malate level. In the first two experiments, three Kalanchoë interspecific hybrid cultivars were exposed to moderate (60%) or high (90%) RH. Both leaves that expanded at high RH and leaves that had expanded at moderate RH and were subsequently exposed to high RH (for nine days) showed increased stomatal conductance. In the third experiment, both C3 and CAM state plants of one K. blossfeldiana cultivar were exposed to low (40%), moderate (60%) or high (90%) RH. Plant transpiration during night-time was inversely related to ambient RH in either state, whereas during day-time a significant effect was only noted at 90% RH. Kalanchoë leaves showed a very effective control of water loss upon water deprivation, especially in the CAM state. Following a single week exposure to 90% RH, detached leaves showed increased rates of water loss during desiccation in C3 state plants. No effect of high RH on stomatal response to desiccation was noted in leaves detached from plants in CAM-state. It is concluded that the negative effect of either growth or one-week exposure to high RH is restricted to the C3 state in Kalanchoë.
De novo assembly, functional annotation, and analysis of the giant reed (Arundo donax L.) leaf transcriptome provide tools for the development of a biofuel feedstock
Evangelistella, Chiara ; Valentini, Alessio ; Ludovisi, Riccardo ; Firrincieli, Andrea ; Fabbrini, Francesco ; Scalabrin, Simone ; Cattonaro, Federica ; Morgante, Michele ; Mugnozza, Giuseppe Scarascia ; Keurentjes, Joost J.B. ; Harfouche, Antoine - \ 2017
Biotechnology for Biofuels 10 (2017). - ISSN 1754-6834 - 24 p.
Arundo donax - Biofuel - Carbon fixation - De novo leaf transcriptome - Genic-SSRs - Phenylpropanoid - Purine and thiamine metabolism - RNA-Seq - SAPs - Stomata
Background: Arundo donax has attracted renewed interest as a potential candidate energy crop for use in biomass-to-liquid fuel conversion processes and biorefineries. This is due to its high productivity, adaptability to marginal land conditions, and suitability for biofuel and biomaterial production. Despite its importance, the genomic resources currently available for supporting the improvement of this species are still limited. Results: We used RNA sequencing (RNA-Seq) to de novo assemble and characterize the A. donax leaf transcriptome. The sequencing generated 1249 million clean reads that were assembled using single-k-mer and multi-k-mer approaches into 62,596 unique sequences (unitranscripts) with an N50 of 1134 bp. TransDecoder and Trinotate software suites were used to obtain putative coding sequences and annotate them by mapping to UniProtKB/Swiss-Prot and UniRef90 databases, searching for known transcripts, proteins, protein domains, and signal peptides. Furthermore, the unitranscripts were annotated by mapping them to the NCBI non-redundant, GO and KEGG pathway databases using Blast2GO. The transcriptome was also characterized by BLAST searches to investigate homologous transcripts of key genes involved in important metabolic pathways, such as lignin, cellulose, purine, and thiamine biosynthesis and carbon fixation. Moreover, a set of homologous transcripts of key genes involved in stomatal development and of genes coding for stress-associated proteins (SAPs) were identified. Additionally, 8364 simple sequence repeat (SSR) markers were identified and surveyed. SSRs appeared more abundant in non-coding regions (63.18%) than in coding regions (36.82%). This SSR dataset represents the first marker catalogue of A. donax. 53 SSRs (PolySSRs) were then predicted to be polymorphic between ecotype-specific assemblies, suggesting genetic variability in the studied ecotypes. Conclusions: This study provides the first publicly available leaf transcriptome for the A. donax bioenergy crop. The functional annotation and characterization of the transcriptome will be highly useful for providing insight into the molecular mechanisms underlying its extreme adaptability. The identification of homologous transcripts involved in key metabolic pathways offers a platform for directing future efforts in genetic improvement of this species. Finally, the identified SSRs will facilitate the harnessing of untapped genetic diversity. This transcriptome should be of value to ongoing functional genomics and genetic studies in this crop of paramount economic importance.
Stomatal characteristics and desiccation response of leaves of cut chrysanthemum (Chrysanthemum morifolium) flowers grown at high air humidity
Aliniaeifard, S. ; Meeteren, Uulke Van - \ 2016
Scientia Horticulturae 205 (2016). - ISSN 0304-4238 - p. 84 - 89.
Chrysanthemum morifolium - Postharvest - Relative humidity - Stomata - Vapour pressure deficit - VPD
Although it is well known that, as a short-term response, stomata close at low relative humidity (RH) (high Vapour Pressure Deficit) and open at high RH (low Vapour Pressure Deficit), effects of long-term exposure to different Vapour Pressure Deficits (VPD's) have only been studied in a few economically important horticultural crops, especially cut roses. To save energy costs, often low VPD conditions are present in greenhouses, due to low ventilation. We studied stomatal and desiccation responses of leaves of cut chrysanthemums after the plants had been exposed to different VPD conditions. While lower transpiration rate (E) was recorded for plants growing at low VPD (L-plants) in comparison with growth at moderate VPD (M-plants), higher stomatal conductance (gs) was found in L-plants compared to M-plants. Bigger size of stomata and higher stomatal density were observed in L-plants. Besides differences in gs, E and stomatal characteristics during growth of the plants at different VPDs, stomatal closure response to desiccation (under the same VPD condition) was different when plants had been grown before at different VPD's. Following desiccation, leaves of L-plants showed higher E compared with M-plants. Also E of leaves grown at moderate VPD but exposed to low VPD for only 5 days (M → L-plants) decreased less as response to desiccation than E of M-plants. After rapid desiccation, leaves of L and M → L plants had larger stomatal openings compared with leaves that were grown continuous at M condition, as indicated by their PSII efficiencies under non-photorespiratory conditions (ΦPSII). In conclusion, control of VPD during growth will be important to prevent subsequent wilting of leaves of chrysanthemum cut flowers.