Contribution of phosphorus (32P) absorption and remobilization for citrus growth
Background and aims
Phosphorus (P) is a mobile nutrient in the plant so growth depends on its internal remobilization and a plant’s ability to respond to its availability in the growing media. This study was conducted to evaluate the influence of P status and rootstocks on the patterns of P uptake and remobilization in orange trees.
Sweet orange trees on Cleopatra mandarin (CM) or Rangpur lime (RL) rootstocks were grown for nine months in nutrient solution (NS) that was either P-deficient (DNS) or was P-sufficient (SNS). After this period, half of the trees were reciprocally transferred between DNS and SNS (from D to S and S to D), while the others remained in their initial P availability.
Trees on RL had more shoot and root growth, accumulated more P and had greater efficiency of P absorption and transport to the shoot (PAE) than those on CM. The major source of P for growth was previously stored P even with an adequate current P supply to the roots. This suggested the dominance of P remobilization over P uptake and the requirement that trees had sufficient stored P to meet P demand of new growth. Trees on CM had greater concentrations of remobilized P in new shoots than trees on RL.
Trees grafted on rootstocks less able to take up P (CM) were more dependent on the internal reserves of P for new growth than rootstocks with higher PAE (RL).
KeywordsNutritional stress Nutrient solution Rootstock varieties Root growth Uptake efficiency
We thank the São Paulo State Research Foundation (FAPESP) for financial support (process 2007/04634-3).
- Bataglia OC, Furlani AMC, Teixeira JPF, Furlani PR, Gallo JR (1983) Método de análise química de plantas. Instituto Agronômico, CampinasGoogle Scholar
- Lea-Cox JD, Syvertsen JP (2001) Springtime 15nitrogen uptake, partitioning, and leaching losses from young bearing Citrus trees of differing nitrogen status. J Amer Soc Hort Sci 126:242–251Google Scholar
- Milla R, Castro-Díez P, Maestro-Martínesz M, Monserrat-Martí G (2005) Relationships between phenology and the remobilization of nitrogen, phosphorus and potassium in branches of eight Mediterranean evergreens. New Phytol 168:167–178. doi: 10.1111/j.1469-8137.2005.01477.x PubMedCrossRefGoogle Scholar
- Misson J, Raghothama KG, Jain A, Jouhet J, Block MA, Bligny R, Ortet P, Creef A, Reef A, Somerville S, Rolland N, Doumas P, Narcy P, Herrera-Estrella L, Nussaume L, Thibaud M (2005) A genome-wide transcriptional analysis using Arabidopsis thaliana Affymetrix gene chips determined plant responses to phosphate deprivation. Proc Natl Acad Sci 102:11934–11939. doi: 10.1073/pnas.0505266102 PubMedCrossRefGoogle Scholar
- Morcuende R, Bari R, Gibon Y, Zheng W, Pant BD, Bläsing O, Bjorn U, Czechowski T, Udvardi MK, Stitt M, Scheible (2007) Genome-wide reprogramming of metabolism and regulatory networks of Arabidopsis in response to phosphorus. Plant Cell Environ 30:85–112. doi: 10.1111/j.1365-3040.2006.01608.x PubMedCrossRefGoogle Scholar
- Nascimento Filho VF, Lobão AE (1977) Detecção de 32P em amostras de origem animal e vegetal por efeito Cerenkov, cintilação líquida e detector GM. CENA/USP, PiracicabaGoogle Scholar
- Sarruge JR (1975) Soluções nutritivas. Summa Phytopatol 1:231–233Google Scholar
- Syvertsen JP, Graham JH (1985) Hydraulic conductivity of roots, mineral nutrition, and leaf gas exchange of citrus rootstocks. J Amer Soc Hort Sci 110:865–869Google Scholar
- Usuda H (1995) Phosphate deficiency in maize. V. mobilization of nitrogen and phosphorus within shoots of young plants and its relationship to senescence. Plant Cell Physiol 36:1041–1049Google Scholar
- Wutscher HK (1989) Alteration of fruit tree nutrition through rootstocks. HortSci 24:578–584Google Scholar