| Full text | |
| Author(s): |
Mateus, Nikolas de Souza
[1]
;
de Oliveira Ferreira, Eric Victor
[2]
;
Arthur Junior, Jose Carlos
[3]
;
Domec, Jean-Christophe
[4]
;
Jordan-Meille, Lionel
[4]
;
de Moraes Goncalves, Jose Leonardo
[5]
;
Lavres, Jose
[1]
Total Authors: 7
|
| Affiliation: | [1] Univ Sao Paulo, Ctr Energia Nucl Agr, 303 Ave Centenario, BR-13416000 Piracicaba, SP - Brazil
[2] Univ Fed Rural Amazonia, Campus Capitao Pogo, BR-68650000 Capitao Poco, PA - Brazil
[3] Univ Fed Rural Amazonia, Inst Florestal, BR 465 Km 7, BR-23897000 Seropedica, RJ - Brazil
[4] INRA, ISPA, Bordeaux Sci Agro, F-33140 Villenave Dornon - France
[5] Univ Sao Paulo, Paulo Escola Super Agr Luiz de Queiroz, 11 Ave, BR-13418900 Piracicaba, SP - Brazil
Total Affiliations: 5
|
| Document type: | Journal article |
| Source: | Plant Physiology and Biochemistry; v. 137, p. 102-112, APR 2019. |
| Web of Science Citations: | 0 |
| Abstract | |
Potassium (K) is the most required macronutrient by Eucalyptus, while sodium (Na) can partially substitute some physiological functions of K and have a positive response on plant growth in K-depleted tropical soils. However, the right percentage of K substitution by Na is not yet known for Eucalyptus seedlings, since a few experiments have only compared treatments receiving K or Na. This study evaluated five levels of Na supply (0, 0.45, 0.90, 1.35 and 1.80 mM) as substitution for K in Eucalyptus seedlings grown in nutrient solution. Plants growth, biomass, K-nutritional status, leaf gas exchange, leaf carbon isotopic composition (delta C-13 parts per thousand) leaf water potential (Psi(w)), leaf area (LA), stomatal density (SD) and water use efficiency (WUE) were measured. The highest total biomass yield was achieved by the Na estimated rate of 0.25 mM, corresponding to a leaf K: Na ratio of 3.41, and having the lowest delta C-13 values. Conversely, the highest Na rate (1.8 mM) induced K deficiency symptoms, lower growth, reduced total dry matter yield, leaf gas exchange, LA, SD and a higher delta C-13, which presented a trend to an inverse correlation with CO2 assimilation rate (A), WUE and shoot dry matter. Collectively, our results conclude that substitution of 25% of K by Na (0.45 mM of Na) provided significant gains in nutritional status and positive plant physiological responses by increasing WUE, stomata! diffusion, and by augmenting CO2 uptake efficiency. This nutritional management can therefore be an alternative option to optimize yields and resource use efficiencies in Eucalyptus cultivation. (AU) | |
| FAPESP's process: | 14/16397-0 - Suprimento de potássio, sódio e silício às mudas de eucalipto |
| Grantee: | Nikolas de Souza Mateus |
| Support Opportunities: | Scholarships in Brazil - Scientific Initiation |