A new addition to the bibliography on stomata

Photo credit: Google

Our lists of references on stomata are still far from complete. Don’t worry, I will continue to collect as much as possible all the bibliographical data on stomata and, wherever possible, publish the abstract of the publications.

It goes without saying that all scientists working on stomata can help me a lot in sending me their own references (and abstracts !).

THIS IS MY FREE OFFER TO ALL PEOPLE INTERESTED IN PLANT STOMATA

With this blog we intend to build a sort of an encyclopedia on plant stomata. Therefore we are screening the literature for interesting publications of which we try to re-publish the bibliographical data, the abstract and one or more photos.

Of course, a lot of these data on stomata publications cannot be found on the internet.  They remain somewhere in libraries, which makes it very difficult for researchers to consult them.

Hence, our main goal is to offer to all people interested in plant stomata a platform to facilitate the notoriety of their publications. Through this blog, you can announce the existence of your publications to all “stomata lovers”.

PLEASE GO TO OUR “ARTICLE SUBMISSION FORM“(SEE LEFT COLUMN AT THE FRONT PAGE OF THIS BLOG) AND ENTER INFORMATION ABOUT THE STOMATA-RELATED ARTICLES THAT YOU WOULD LIKE TO SUBMIT FOR INCLUSION IN OUR REFERENCE LIST.

Let us reach hands ! Let us build this free encyclopedia together !

The gene that controls the distribution of stomatal cells

 

Stomatal cell growth gene found in plants

The Free Library (2002)

Countryside Publications Ltd. 29 Jun. 2015 http://www.thefreelibrary.com/Stomatal+cell+growth+gene+found+in+plants.-a090871621

Remember the article on Sonic Bloom foliar feeding in the last issue (86/43 pg. 72)? Well, researchers at Ohio State University have identified the gene that controls the distribution of stomatal cells on leaves, key components for the healthy growth of all plants.

The discovery may have implications for enhancing the growth of important crop plants and might even provide an alternative of sorts for research into human stem cells.

The finding, reported in the current issue of the journal Science, linked the TMM gene in Arabidopsis plants to the formation and distribution of stomatal cells on the surfaces of leaves.

Arabidopsis thaliana is for botanists what fruit flies are for animal geneticists. It is one of the most important–and best understood–models for scientific study. While this common mustard plant has little economic value, it is widely used to better understand the processes governing plant growth.

Fred Sack, a professor of plant biology at Ohio State University, and Jeanette Nadeau, a postdoctoral fellow in the same department, spent several years trying to understand how the TMM gene altered the number and arrangement of stomatal cells on leaves. Now they have discovered that TMM is only the second known gene to be involved in stomatal development in plants.

“Genes like TMM exist in crop plants such as rice,” Sack said. “If TMM has the same function in crop plants that it does in Arabidopsis, then it could be a key regulator.”
Stomatal cells function as pores on the underside of leaves and control the entry of gases into the leaf for photosynthesis.

Read the full article: The Free Library

Stomatal characteristics, tissue ion relations, and salinity tolerance

 

Linking osmotic adjustment and stomatal characteristics with salinity stress tolerance in contrasting barley accessions

by Zhu M., Zhou M., Shabala L., Shabala S. (2015)

in Functional Plant Biology, 42, (3) pp. 252-263. ISSN 1445-4408 (2015)

Abstract

Salinity tolerance is a complex trait – both physiologically and genetically – and the issue of which mechanism or trait has bigger contribution towards the overall plant performance is still hotly discussed in the literature.

In this work, a broad range of barley (Hordeum vulgare L. and Hordeum spontaneum L.) genotypes contrasting in salinity stress tolerance were used to investigate the causal link between plant stomatal characteristics, tissue ion relations, and salinity tolerance. In total, 46 genotypes (including two wild barleys) were grown under glasshouse conditions and exposed to moderate salinity stress (200 mM NaCl) for 5 weeks. The overall salinity tolerance correlated positively with stomata density, leaf K⁺ concentration and the relative contribution of inorganic ions towards osmotic adjustment in the shoot. At the same time, no correlation between salinity tolerance and stomatal conductance or leaf Na⁺ content in the shoot was found. Taken together, these results indicate the importance of increasing stomata density as an adaptive tool to optimise efficiency of CO₂ assimilation under moderate saline conditions, as well as benefits of the predominant use of inorganic osmolytes for osmotic adjustment in barley. Another finding of note was that wild barleys showed rather different strategies dealing with salinity, as compared with cultivated varieties.

See the text: UTAS

Auxin homeostasis in stomata

 

Auxin homeostasis for stomatal function and stress response

Feraru E., Project Leader (2015-2017)

BOKU Research Units, Institute of Applied Genetics and Cell Biology (IAGZ)

Abstract

Auxin has been suggested to affect stomata function, but an auxin role in stomata movement remained largely enigmatic. My results suggest that subcellularly defined auxin homeostasis plays a role in environmentally controlled stomata movement. Based on this initial insight, I propose to further investigate the role of auxin in stomata-dependent stress adaptation. Initially, I will further address the functional redundancy of stomata expressed PILSes, will determine the cellular function of PILS proteins in guard cell, and unravel intrinsic and extrinsic signals for PILS-dependent stomatal function.
Altogether, in this research project, I aim to investigate the role of (PILS-mediated) auxin homeostasis in stomatal function. My research will reveal how auxin homeostasis-mediated stomatal function contributes to stress adaptive responses, such as drought. This line of research has importance for plant productivity and survival.

See the text: FIS

The possible functions of ICE genes from grape in stomatal development

Analysis of the Role of Grape ICE Proteins in the CBF Pathway and Stomatal Development

by Rahman M. (2015)

Arabidopsis ICE (Inducer of CBF expression) transcription factors play a role in freezing tolerance and stomatal development. This thesis examined the possible functions of ICE genes from grape. Four ICE genes were isolated and sequenced from both the freezing tolerant wild species Vitis riparia and the freezing sensitive cultivated species V. vinifera. All the encoded ICE proteins contain a bHLH domain with an ICE-specific sequence in their highly conserved C-terminus, and only a few amino acid differences between the ICE orthologs. RT-PCR analyses and sequencing showed that all genes produced spliced transcripts in leaves and buds at ambient and low temperature conditions. In addition, the alternative transcripts ICE1i1, ICE2i2 and ICE4i1 were detected in leaves but only ICE1i1 in mature buds. The functions of the various ICE variants in the CBF pathway were analyzed by Agrobacterium-mediated transactivation experiments. The results showed that all ICE proteins can activate the CBF4 promoter, albeit especially ICE2 and ICE3, via a MYC2g element. Cold increased activation, presumably because of cold-induced sumoylation that stabilizes these proteins. ICE1 and ICE4 induced the transcription better from CBF6 promoter, via different MYC elements. The truncated ICE proteins encoded by alternative transcripts were found to give a lower activation compared to their corresponding regular proteins. Homologs of the Arabidopsis stomatal genes SPCH, MUTE and FAMA were isolated and sequenced from wild and wine grape species. Each of these stomatal genes produced regular spliced transcripts, which for FAMA included 2 transcripts with different start sites, early FAMA(E) and late FAMA(L). The sequential presence of SPCH, MUTE and FAMA transcripts in different aged leaves and the effect of transient overexpression of these genes and of ICE genes on the formation of stomata and pavement cells supports their respective functions in three consecutive stages of stomatal development. The role of proteins encoded on alternatively spliced transcripts, SPCHi1, MUTEi1 FAMAi1(E) and FAMAi2(L), is as yet unclear. Transactivation results suggest that grape ICEs interact with grape FAMA(L) to activate VrCBF4, possibly to regulate both stomatal development and the freezing tolerance pathway. A model which suggests a role for all ICE and stomatal genes in either stomatal development or/and the acquisition of freezing tolerance is presented.

See the text: University of Guelph

A stomatal ozone flux model

 

Assessment of a stomatal ozone flux model in Astronium graveolens Jacq

by Cassimiro J. C. (2015)

Instituto de Botânica. Secretaria do Meio Ambiente (São Paulo – Estado). São Paulo, SP, Brazil

Abstract
The concentrations of ozone (O3) have increased annually in both urban and rural areas, which can result in reduced agricultural productivity and damage to plant species, communities and ecosystems. It is necessary to know the O3-induced effects on plants to determine the concentration threshold that should not be overcome to ensure the protection of species and vegetation.

In Brazil there is no vegetation index of protection against the effects of this pollutant. The first indices used were based on averages of concentration or the sum of hourly concentrations and showed poor correlation with the plant responses. Currently the research has been focus on indices based on stomatal conductance.

This study aims to obtain data with Astronium graveolens Jacq., an O3-sensitive species to insert in a model of stomatal conductance flux of O3 and evaluate their applicability in our country. Seedlings of A. graveolens will be exposed for four three-month periods in contaminated site by O3. The weather conditions and the concentration of pollutants in the study area will be monitored continuously. Daily courses of stomatal conductance under various environmental conditions will be done weekly. The results will be applied to the model in which stomatal conductance is multiplied by the relative values of factors that modulate such as temperature, vapor pressure deficit, photosynthetically active radiation, ozone concentration and water content of the soil. The presence of foliar injury induced by O3 is used as the response variable. This study will obtain data that could support proposals for an index of tropical species protection against the effects of O3. (AU)

 

Stomata in Morus (Moraceae)

 

STUDIES ON MICROMORPHOLOGY AND KARYOTYPE ANALYSIS OF THREE MULBERRY GENOTYPES (MORUS SPP.)

by Venkatesh K. H. (2015)

===

in American Journal of Phytomedicine and Clinical Therapeutics; Vol 3, No 2 (2015):

Abstract

The study of karyotype is of great value in modern taxonomy for evolving progeny of different ploidy levels of hybridization. Stomatal frequencies are important parameters while selecting drought resistant genotypes as being correlated with drought and disease resistant. Micro-morphology, chromosome numbers and characters of three indigenous mulberry cultivars were studied. S₁₃ and V₁ are diploid with 2n=28 and Tr-₈ is triploid with 2n=42 somatic chromosomes numbers respectively. Somatic chromosome length ranges from 1.29µm to 2.59µm where as an arm ratio ranges from 0.49 to 0.97µm. Their karyotypes were commonly bi-modal, decreasing in length from the longest to the shortest chromosomes. Experimental results have confirmed that, out of three varieties studied two are diploids with 2n=28 and one variety showed 2n=42 chromosomes.

Lesser frequency of stomata in triploid than diploid varieties.  Stomatal frequency and size decrease with increase in ploidy level. It can be suggested that triploid with lesser stomatal frequency are suitable for breeding triploids resistant to drought conditions.

See the text: AJPCT Reading Tools

Stomatal regulation and carbon isotope fractionation

Photorespiration contributes to stomatal regulation and carbon isotope fractionation : a study with barley, potato and Arabidopsis plants deficient in glycine decarboxylase

by Igamberdiev A. U., Mikkelsen T. N., Ambus P., Bauwe H., Lea P. J.,  Gardeström P. (2004) .

in Photosynthesis Research, 81 (2). pp. 139-152. ISSN 0166-8595

Abstract

The rates of respiration in light and darkness, C i/C a and carbon isotope fractionation were investigated in glycine decarboxylase-deficient plants of barley, potato and Arabidopsis thaliana grown in climate chambers with controlled light intensity, temperature, humidity, irradiation and different CO2 concentrations (360, 700 and 1400 µl l–1) and compared to the wild-type plants.

All photorespiration-impaired plants exhibited higher C i/C a and corresponding lower apparent water-use efficiencies, which were more expressed under high irradiance and elevated temperature. The mutants were depleted in 13C as compared to the wild-type plants, with a difference of up to 6 following growth in 360 µl l–1 CO2.

We determined the carbon isotope content at different CO2 concentrations to calculate the contribution of both C i/C a and photorespiration for 13C/12C fractionation. The direct effect of photorespiration was in the range of 0.7–1.0, from which we calculated the value of fractionation at the site of glycine decarboxylation as being 10–13, which is in agreement with the previously reported carbon isotope discrimination exerted by the glycine decarboxylase.

Respiratory rates, particularly in the light, were increased in the glycine decarboxylase mutants. The necessity of the maintenance of a high CO2 concentration near the site of carboxylation in chloroplasts in plants deficient in photorespiratory enzymes, requires an increased opening of the stomata with a corresponding decrease in water-use efficiency.

It is concluded that photorespiration participates in the regulation of C i/C a and contributes to carbon isotope fractionation, both via effects on stomata and via discrimination of 13C in the glycine decarboxylase reaction.

See the text: Lancaster University

Natural variation of stomatal abundance in Macadamia species

 

Pericarps retained in the tree canopy and stomatal abundance are components of resistance to husk spot caused by Pseudocercospora macadamiae in Macadamia

by Akinsanmi O. A., Topp B., Drenth A. (2012)

in Euphytica, 185 2: 313–323. doi:10.1007/s10681-012-0645-9

Abstract

Pseudocercospora macadamiae Beilharz, Mayers and Pascoe infects Macadamia fruit via stomata causing husk spot disease. Information on the variability of fruit stomatal abundance, its association with diseased fruit pericarps (sticktights) that are retained in the tree canopy, and its influence on the husk spot intensity (incidence, severity and lesion number) among Macadamia genotypes is lacking.

We examined a total of 230 Macadamia trees comprising 19 cultivars, 56 wild germplasm accessions and 40 breeding progeny, for the prevalence of sticktights and husk spot intensity over three production seasons. We observed a strong association between the prevalence of sticktights and disease intensity indicating its usefulness as a predictor of husk spot and as a useful phenotypic trait for husk spot resistance selection in breeding programmes.

Similarly, stomatal abundance varied among Macadamia genotypes, and a significant linear relationship (P < 0.001; 93%) was observed between fruit stomatal abundance and husk spot for all the Macadamia genotypes analysed, confirming the utility of that trait for disease resistance screening. The genotypes were grouped into disease resistance groups.

Correlations between fruit stomatal abundance, disease intensity and prevalence of sticktights revealed that the numbers of sticktights, and relative stomatal abundance were the main factors influencing the intensity of husk spot among Macadamia genotypes. This is the first comprehensive study of natural variation of stomatal abundance in Macadamia species that reveals genetic variation, and provides relevant relationships with disease intensity and the prevalence of sticktights. The phenotypic plant traits indentified in this study may serve as selection tools for disease resistance screening in Macadamia breeding programmes.

 

AITC and stomatal closure in Arabidopsis

Allyl isothiocyanate (AITC) induces stomatal closure in Arabidopsis

by Khokon M. A. R., Jahan M. S., Rahman T., Hossain M. A., Muroyama D., Minami I., Munemasa S., Mori I.i C., Nakamura Y., Murata Y. (2011)

in Plant, Cell & Environment, 34 (11). pp. 1900-6. ISSN 1365-3040.

Abstract

Isothiocyanates (ITCs) are degradation products of glucosinolates in crucifer plants and have repellent effect on insects, pathogens and herbivores.

In this study, we report that exogenously applied allyl isothiocyanate (AITC) induced stomatal closure in Arabidopsis via production of reactive oxygen species (ROS) and nitric oxide (NO), and elevation of cytosolic Ca(2+) . AITC-induced stomatal closures were partially inhibited by an inhibitor of NADPH oxidase and completely inhibited by glutathione monoethyl ester (GSHmee). AITC-induced stomatal closure and ROS production were examined in abscisic acid (ABA) deficient mutant aba2-2 and methyl jasmonate (MeJA)-deficient mutant aos to elucidate involvement of endogenous ABA and MeJA.

Genetic evidences have demonstrated that AITC-induced stomatal closure required MeJA priming but not ABA priming.

These results raise the possibility that crucifer plants produce ITCs to induce stomatal closure, leading to suppression of water loss and invasion of fungi through stomata.