Gene expression and physiological responses associated to stomatal functioning in Rosa×hybrida grown at high relative air humidity

Within-leaf heterogeneity in stomatal traits poses a key uncertainty in determining a representative value for the whole leaf. Accounting for this heterogeneity, we studied stomatal initiation on expanding leaves and estimated stomatal conductance (gs) of mature leaves. The entire lamina was evaluated at four percentages of full leaflet elongation (FLE; leaflet length relative to its final length) in Rosa hybrida L. plants grown at 60% relative air humidity (RH), and at 100% FLE following cultivation at elevated (95%) RH. Over 80% of the stomata were initiated between 33 and 67% FLE, whereas stomatal growth mostly occurred afterwards. At 100% FLE, the heterogeneity in stomatal density was the result of uneven stomatal differentiation, while an uneven differentiation of epidermal cells contributed to this variation only at elevated RH. Noticeable within-leaf differences (up to 40%) in gs were calculated at 100% FLE. Avoiding leaflet periphery decreased this heterogeneity. Despite the large promotive effect of elevated RH on stomatal and pore dimensions, the within-leaf variation remained unaffected in all characters, besides pore aperture (and, thus, gs). The noted level of within-leaf variation in stomatal features demands a sampling scheme tailored to the leaf developmental stage, the feature per se and the evaporative demand during growth.

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Root-to-shoot ABA signaling does not contribute to genotypic variation in stomatal functioning induced by high relative air humidity

Environmental and Experimental Botany ◽

10.1016/j.envexpbot.2015.11.001 ◽

2016 ◽

Vol 123 ◽

pp. 13-21 ◽

Cited By ~ 14

Author(s):

Dália R.A. Carvalho ◽

Dimitrios Fanourakis ◽

Maria J. Correia ◽

José A. Monteiro ◽

José Pedro L. Araújo-Alves ◽

...

Keyword(s):

Genotypic Variation ◽

Aba Signaling ◽

Air Humidity ◽

Relative Air Humidity ◽

Stomatal Functioning

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Avoiding high relative air humidity during critical stages of leaf ontogeny is decisive for stomatal functioning

Physiologia Plantarum ◽

10.1111/j.1399-3054.2011.01475.x ◽

2011 ◽

Vol 142 (3) ◽

pp. 274-286 ◽

Cited By ~ 52

Author(s):

Dimitrios Fanourakis ◽

Susana M. P. Carvalho ◽

Domingos P. F. Almeida ◽

Ep Heuvelink

Keyword(s):

Air Humidity ◽

Leaf Ontogeny ◽

Relative Air Humidity ◽

Stomatal Functioning

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Visco-elastic changes of vocal fold mucosa related to high and low relative air humidity

Clinical Otolaryngology ◽

10.1046/j.1365-2273.2000.00358-27.x ◽

2000 ◽

Vol 25 (4) ◽

pp. 329-330

Author(s):

R.J.B. Hemler ◽

G.H. Wieneke ◽

P.H. Dejonckere

Keyword(s):

Vocal Fold ◽

Air Humidity ◽

Relative Air Humidity

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Clinical, epidemiological and climatic factors related to the occurrence of cutaneous leishmaniasis in an endemic area in northeastern Brazil

Brazilian Journal of Biology ◽

10.1590/1519-6984.224937 ◽

2020 ◽

Author(s):

R. S. Oliveira ◽

K. B. A. Pimentel ◽

M. L. Moura ◽

C. F. Aragão ◽

A. S. Guimarães-e-Silva ◽

...

Keyword(s):

Cutaneous Leishmaniasis ◽

Climatic Factors ◽

Wide Distribution ◽

Northeastern Brazil ◽

Public Health Issue ◽

Air Humidity ◽

Disease Occurrence ◽

Relative Air Humidity ◽

Age Range ◽

And Control

Abstract Cutaneous leishmaniasis (CL) is a neglected tropical disease with a wide distribution in the Americas. Brazil is an endemic country and present cases in all states. This study aimed to describe the occurrence, the underlying clinical and epidemiological factors, and the correlation of climatic variables with the frequency of reported CL cases in the municipality of Caxias, state of Maranhão, Brazil. This is a retrospective and descriptive epidemiological study based on data extracted from the Brazilian Information System of Diseases Notification, from 2007 to 2017. Maximum and minimum temperature, precipitation, and relative air humidity data were provided by the Brazilian National Institute of Meteorology. A total of 201 reported autochthonous CL cases were analyzed. The predominance of cases was observed in males (70.1%). The age range between 31 and 60 years old was the most affected, with 96 cases (47.9%). Of the total number of registered cases, 38.8% of the affected individuals were engaged in agriculture-related activities. The georeferenced distribution revealed the heterogeneity of disease occurrence, with cases concentrated in the Western and Southern regions of the municipality. An association was detected between relative air humidity (monthly mean) and the number of CL cases per month (p = 0.04). CL continues to be a concerning public health issue in Caxias. In this context, there is a pressing need to strengthen measures of prevention and control of the disease through the network of health services of the municipality, considering local and regional particularities.

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Responses of Rice Growth to Day and Night Temperature and Relative Air Humidity—Leaf Elongation and Assimilation

Plants ◽

10.3390/plants10010134 ◽

2021 ◽

Vol 10 (1) ◽

pp. 134

Author(s):

Sabine Stuerz ◽

Folkard Asch

Keyword(s):

Leaf Area ◽

Leaf Growth ◽

Crop Growth ◽

Air Humidity ◽

Leaf Elongation ◽

Night Temperature ◽

Relative Air Humidity ◽

Leaf Area Expansion ◽

Plant Level ◽

Area Expansion

Predictions of future crop growth and yield under a changing climate require a precise knowledge of plant responses to their environment. Since leaf growth increases the photosynthesizing area of the plant, it occupies a central position during the vegetative phase. Rice is cultivated in diverse ecological zones largely differing in temperature and relative air humidity (RH). To investigate the effects of temperature and RH during day and night on leaf growth, one variety (IR64) was grown in a growth chamber using 9 day/night regimes around the same mean temperature and RH, which were combinations of 3 temperature treatments (30/20 °C, 25/25 °C, 20/30 °C day/night temperature) and 3 RH treatments (40/90%, 65/65%, 90/40% day/night RH). Day/night leaf elongation rates (LER) were measured and compared to leaf gas exchange measurements and leaf area expansion on the plant level. While daytime LER was mainly temperature-dependent, nighttime LER was equally affected by temperature and RH and closely correlated with leaf area expansion at the plant level. We hypothesize that the same parameters increasing LER during the night also enhance leaf area expansion via shifts in partitioning to larger and thinner leaves. Further, base temperatures estimated from LERs varied with RH, emphasizing the need to take RH into consideration when modeling crop growth in response to temperature.

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Relationship between preterm birth and air pollution in Santos, Sao Paulo, Brazil

European Journal of Public Health ◽

10.1093/eurpub/ckaa166.111 ◽

2020 ◽

Vol 30 (Supplement_5) ◽

Author(s):

M E L Brandao ◽

B A L F Braga ◽

M L C Martins ◽

P L A A Pereira

Keyword(s):

Air Pollution ◽

Preterm Birth ◽

Air Pollutants ◽

First Trimester ◽

Sao Paulo ◽

São Paulo ◽

Air Humidity ◽

Relative Air Humidity ◽

The Impact ◽

Fourth Quartile

Abstract Santos is a seaboard Brazilian city recognized by its port activity where the road and rail infrastructure along with the large transportation operation, displays an important factor to contribute with all kinds of toxic and air pollutants. Recent studies have suggested associations between air pollution and various birth outcomes. Pollutant gases such as NOx, O3 and particulate matter PM2,5, PM10 have been cited as factors involved in such outcomes. The present study aims to assess the relationship between atmospheric pollutants and perinatal outcomes in the city of Santos from Jan. 2012 to Dec. 2015. Cross-sectional study that analyzed 10.319 singleton births in an area set with 2 km radius of the monitoring stations. Birth weight and information on mother and pregnancy were obtained at the Brazilian “Born Alive National Information System”. Daily records of air pollutants (PM10, PM2.5, NO2 and O3), temperature and relative air humidity, for the study period, were obtained from São Paulo State Environmental Agency (CETESB). Associations between preterm birth and air pollutants mean levels at each gestational trimester were investigated using multiple logistic regression model controlled by the variables: infant sex, type of delivery, maternal education. prenatal care, and number of previous live births, temperature and relative air humidity. NO2 e PM2,5 was not associated with preterm birth. O3 was significantly associated in the first trimester in the fourth quartile (OR = 1,47 CI 95% 1,05; 2,07). PM10 was significantly associated in the first trimester for the fourth quartile (OR = 1,28 CI 95% 1,00; 1,64), second trimester for the second quartile (OR = 1,37 CI 95% 1,07; 1,77). Conclusions the results shows evidence that maternal exposure to air pollution especially during the first trimester of pregnancy may contribute to preterm birth. Further actions are needed towards controlling air pollution are strongly recommended for promoting early-life health. Key messages This is the first research of this kind that was made in Santos. It brings important evidence of the impact in the life of the population, especially those whose is not even born yet. It can be used as a resource to guide public policies in health, especially the guidelines that dictate the concentration of air pollutants and air quality.

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Transcriptional analysis of the response of C. elegans to ethanol exposure

Scientific Reports ◽

10.1038/s41598-021-90282-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mark G. Sterken ◽

Marijke H. van Wijk ◽

Elizabeth C. Quamme ◽

Joost A. G. Riksen ◽

Lucinda Carnell ◽

...

Keyword(s):

Gene Expression ◽

Physiological Response ◽

Physiological Responses ◽

Ethanol Exposure ◽

Transcriptional Analysis ◽

Transcriptional Responses ◽

Genetic Pathways ◽

C Elegans ◽

Chronic Ethanol Consumption ◽

Transcriptional Changes

AbstractEthanol-induced transcriptional changes underlie important physiological responses to ethanol that are likely to contribute to the addictive properties of the drug. We examined the transcriptional responses of Caenorhabditis elegans across a timecourse of ethanol exposure, between 30 min and 8 h, to determine what genes and genetic pathways are regulated in response to ethanol in this model. We found that short exposures to ethanol (up to 2 h) induced expression of metabolic enzymes involved in metabolizing ethanol and retinol, while longer exposure (8 h) had much more profound effects on the transcriptome. Several genes that are known to be involved in the physiological response to ethanol, including direct ethanol targets, were regulated at 8 h of exposure. This longer exposure to ethanol also resulted in the regulation of genes involved in cilia function, which is consistent with an important role for the effects of ethanol on cilia in the deleterious effects of chronic ethanol consumption in humans. Finally, we found that food deprivation for an 8-h period induced gene expression changes that were somewhat ameliorated by the presence of ethanol, supporting previous observations that worms can use ethanol as a calorie source.

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