Why are Chloris gayana leaves shorter in salt-affected plants? Analyses in the elongation zone

Reduced hydraulic conductance calculated from growth data was suggested to be the main reason for reduced leaf expansion in salt-stressed Chloris gayana (Rhodes grass). In this work, xylem vessel cross-sections and wall enzyme activities were analysed to re-examine the effects of salinity on leaf gr...

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Autores principales: Ortega, Leandro Ismael, Fry, Stephen C., Taleisnik, Edith
Formato: info:ar-repo/semantics/artículo
Lenguaje:Inglés
Publicado: Society for Experimental Biology 2020
Materias:
Acceso en línea:http://hdl.handle.net/20.500.12123/7449
https://academic.oup.com/jxb/article/57/14/3945/587712
https://doi.org/10.1093/jxb/erl168
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author Ortega, Leandro Ismael
Fry, Stephen C.
Taleisnik, Edith
author_browse Fry, Stephen C.
Ortega, Leandro Ismael
Taleisnik, Edith
author_facet Ortega, Leandro Ismael
Fry, Stephen C.
Taleisnik, Edith
author_sort Ortega, Leandro Ismael
collection INTA Digital
description Reduced hydraulic conductance calculated from growth data was suggested to be the main reason for reduced leaf expansion in salt-stressed Chloris gayana (Rhodes grass). In this work, xylem vessel cross-sections and wall enzyme activities were analysed to re-examine the effects of salinity on leaf growth in this species. Maximal segmental growth rates were 20% lower and the growth zone was 23% shorter in leaves from salinized plants than in controls; however, growth rates between 0 mm and 15 mm from the ligule were similar in both types of leaves. Xylem cross-sectional areas in this region were about 65% smaller in leaves of salinized plants, suggesting that hydraulic restrictions in the leaves of salinized plants were much higher than overall growth reductions. Extractable xyloglucan endotransglucosylase activity in this zone was twice as high in leaves of salinized plants as in leaves of controls. Nevertheless, the activity of the extracted enzyme was not affected by up to 1 M NaCl added to the reaction medium. Therefore, increased xyloglucan endotransglucosylase activity under salinity may be due to a promotion of transcription of XTH (xyloglucan endotransglucosylase/hydrolases) genes and/or translation of preformed transcripts. These results suggest that, as in drought stress, increased activity of cell wall enzymes associated with wall loosening may contribute to the maintenance of growth under saline conditions despite hydraulic restrictions.
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institution Instituto Nacional de Tecnología Agropecuaria (INTA -Argentina)
language Inglés
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publishDateRange 2020
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publisherStr Society for Experimental Biology
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spelling INTA74492020-06-22T13:52:27Z Why are Chloris gayana leaves shorter in salt-affected plants? Analyses in the elongation zone Ortega, Leandro Ismael Fry, Stephen C. Taleisnik, Edith Chloris gayana Peroxídasas Estrés Osmótico Xilema Peroxidases Osmotic Stress Xylem Grama Rhodes Estrés Salino Rhodes Grass Reduced hydraulic conductance calculated from growth data was suggested to be the main reason for reduced leaf expansion in salt-stressed Chloris gayana (Rhodes grass). In this work, xylem vessel cross-sections and wall enzyme activities were analysed to re-examine the effects of salinity on leaf growth in this species. Maximal segmental growth rates were 20% lower and the growth zone was 23% shorter in leaves from salinized plants than in controls; however, growth rates between 0 mm and 15 mm from the ligule were similar in both types of leaves. Xylem cross-sectional areas in this region were about 65% smaller in leaves of salinized plants, suggesting that hydraulic restrictions in the leaves of salinized plants were much higher than overall growth reductions. Extractable xyloglucan endotransglucosylase activity in this zone was twice as high in leaves of salinized plants as in leaves of controls. Nevertheless, the activity of the extracted enzyme was not affected by up to 1 M NaCl added to the reaction medium. Therefore, increased xyloglucan endotransglucosylase activity under salinity may be due to a promotion of transcription of XTH (xyloglucan endotransglucosylase/hydrolases) genes and/or translation of preformed transcripts. These results suggest that, as in drought stress, increased activity of cell wall enzymes associated with wall loosening may contribute to the maintenance of growth under saline conditions despite hydraulic restrictions. Instituto de Fisiología y Recursos Genéticos Vegetales Fil: Ortega, Leandro Ismael. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales (ex IFFIVE); Argentina Fil: Fry, Stephen C. University of Edinburgh. Institute of Molecular Plant Sciences. The Edinburgh Cell Wall Group; Gran Bretaña Fil: Taleisnik, Edith. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales (ex IFFIVE); Argentina. 2020-06-22T13:01:06Z 2020-06-22T13:01:06Z 2006-11 info:ar-repo/semantics/artículo info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://hdl.handle.net/20.500.12123/7449 https://academic.oup.com/jxb/article/57/14/3945/587712 0022-0957 1460-2431 https://doi.org/10.1093/jxb/erl168 eng info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) application/pdf Society for Experimental Biology Journal of Experimental Botany 57 (14) : 3945–3952. (November 2006)
spellingShingle Chloris gayana
Peroxídasas
Estrés Osmótico
Xilema
Peroxidases
Osmotic Stress
Xylem
Grama Rhodes
Estrés Salino
Rhodes Grass
Ortega, Leandro Ismael
Fry, Stephen C.
Taleisnik, Edith
Why are Chloris gayana leaves shorter in salt-affected plants? Analyses in the elongation zone
title Why are Chloris gayana leaves shorter in salt-affected plants? Analyses in the elongation zone
title_full Why are Chloris gayana leaves shorter in salt-affected plants? Analyses in the elongation zone
title_fullStr Why are Chloris gayana leaves shorter in salt-affected plants? Analyses in the elongation zone
title_full_unstemmed Why are Chloris gayana leaves shorter in salt-affected plants? Analyses in the elongation zone
title_short Why are Chloris gayana leaves shorter in salt-affected plants? Analyses in the elongation zone
title_sort why are chloris gayana leaves shorter in salt affected plants analyses in the elongation zone
topic Chloris gayana
Peroxídasas
Estrés Osmótico
Xilema
Peroxidases
Osmotic Stress
Xylem
Grama Rhodes
Estrés Salino
Rhodes Grass
url http://hdl.handle.net/20.500.12123/7449
https://academic.oup.com/jxb/article/57/14/3945/587712
https://doi.org/10.1093/jxb/erl168
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