IN VITRO CULTURE REVEALS DIFFERENCES IN THE ORGAN RESPONSIBLE FOR CITRUS RESPONSES TO OSMOTIC OR SALT STRESS

In vitro tissue culture techniques can overcome some of the limitations found in the study of plant physiology under abiotic stress conditions in experiments conducted in the field or in greenhouses.
In this work, the effect of two abiotic stress conditions on ‘Carrizo’ citrange plants, one of the most important citrus rootstock used in citrus industry, was studied.
Micropropagated shoots, growing under salt- or osmotic-stress, showed symptoms of leaf damage very similar to those found in intact plants.
Malondialdehyde accumulated only in stressed shoots but not in those cultured under elevated salt conditions.
Similarly, increases in proline concentration were observed only in shoots under osmotic-stress conditions.
Differences were also observed in the hormonal regulation of the shoots.
Abscisic acid concentration increased in shoots grown under osmotic stress conditions whereas no differences with the controls were observed in salt-stressed plants.
It has been previously shown that ‘Carrizo’ citrange intact plants accumulated important amounts of abscisic acid and proline in their leaves when cultivated in greenhouses under both osmotic- or salt-stress conditions.
The results suggest that some of the key responses of citrus to salt stress depend on the presence of the root whereas, under osmotic stress conditions, physiological responses occur in shoots independent of the root.

VII International Symposium on In Vitro Culture and Horticultural Breeding

R.M. Pérez-Clemente, A. Montoliu, C. de Ollas, M.F. López, V. Arbona, A. Gómez-Cadenas

citrus, in vitro, abiotic stress, oxidative stress, proline

https://doi.org/10.17660/ActaHortic.2012.961.44