Effect of Cytokinins on P granatum Cuttings Inoculated with G. intrarradices on Drought Stress

BOMPADRE MJ.; DIVO DE SESAR M.; RODRIGUEZ MA.; FERNÁNDEZ L.; SILVANI V.; PÉRGOLA M.; NAVARRO L.; GODEAS A.

Rosario, Santa Fe, Argentina

Congreso; XLII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2006

Arbuscular micorrizas are mutualistic fungi that colonize roots of mostly plants. In general, this association produces a nutricional improvement (P2, N2 and H2O from microagregates where roots can’t take them) of the host and they Exchange photosintates. Cytokinins are vegetal hormones that characteristically retard senescente. Our objective was to evaluate the effect of mycorrhiza in combination with cytokinins and drought stress. Cuttings of Punica granatum were inoculated with Glomus intraradices; half of them received 3 applications from aspersión with a solution of cytokinins (5 mg/ml), each cutting received o,5 ml per application. A half was well watered whereas the other was watered stressed for 10 days. We measured root colonization, chlorophylls “a”, “b” and totals, total poliphenols, soluble proteins, cabalase, ascorbate peroxidase and superoxide dismutase activities. We observe dan improvement on the phenolic content, on the chlorophylls “a” and “b” and protein contents in presence of drought stress (independently of the presence or absence of cytokinins) between inoculated and non inoculated cuttings. Inoculated cuttings presented low levels of cabalase, superoxide dismutase and ascorbate peroxidase levels on drought stress, whereas the non inoculated ones didn’t. In conclusión, micorrizas are more important protectors of drougth stress than cytokinins.