| Texto completo | |
| Autor(es): |
Mateus, Nikolas Souza
;
Florentino, Antonio Leite
;
Moreira, Gabriel Luis Lima Soares
;
Nogueira, Marina Lima
;
Ferreira, Maria Eduarda Pena
;
Rossi, Monica Lanzoni
;
Linhares, Francisco Scaglia
;
Lavres, Jose
Número total de Autores: 8
|
| Tipo de documento: | Artigo Científico |
| Fonte: | PLANT CELL AND ENVIRONMENT; v. N/A, p. 23-pg., 2024-12-11. |
| Resumo | |
While not essential for most plants, sodium (Na+) can partially substitute for potassium (K+) in some metabolic functions. Thus, understanding the mechanisms underlying K+ and Na+ uptake, transport, utilization, and ion replacement is crucial to sustain forest production. A pot experiment was designed with 6 K/Na ratios (100/0, 85/15, 70/30, 55/45, 40/60, and 0/0%) and two water conditions (well-watered, W+; and water-stressed, W-) on two Eucalyptus species with contrasting drought tolerance. In a multi-level analysis, we measured morphological, nutritional, physiological, biochemical, molecular, and anatomical traits. Low to moderate K replacement with Na (85/15%-55/45%) provided partial and faster stomatal closure (lower delta 13C), thereby enhancing plants' water status (WUE, RLWC, Psi PD, Psi MD), photosynthetic capacity (gs, E, A, Ci/Ca), photoprotection (NPQ, qP, ETR, Fv/FM, Phi PSII), and growth (height, collar diameter, LA, TDM) relative to exclusive K supply. The 70/30% K/Na replacement was defined as the ideal ratio, upregulating K+ and water uptake (overexpression of AKT1, PIP2;5, PIP2;7 and TIP1;3), maximizing enzymatic antioxidant performance and biomass production, and reducing oxidative stress. High K replacement with Na (40/60%) and K deficiency (0/0%) led to incomplete stomatal closure reduced water status, photosynthetic capacity, photoprotection, and growth, especially in the species with low drought tolerance. (AU) | |
| Processo FAPESP: | 19/16168-4 - Substituição parcial do K por Na em genótipos de Eucalyptus cultivados sob restrição hídrica: caracterização dos mecanismos bioquímicos, fisiológicos e morfoanatômicos de tolerância ao estresse osmótico |
| Beneficiário: | Nikolas de Souza Mateus |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |