RESUMEN
Two physiological tests for screening drought tolerance of barley (Hordeum vulgare, L.) plants are compared in this work. Water deficit is induced by treating the plants' roots with polyethylene glycol (PEG 8000). The relative water content (RWC) of the plants is used as a measure of the water status. Conductometrically determined electrolyte leakage from the leaf tissue demonstrates the membrane injury caused by dehydration. It is shown that the injury index increases with the decrease of the RWC of the leaves. The F(v)/F(m) ratio is employed to assess changes in the primary photochemical reactions of the photosynthetic apparatus after dehydration. The results suggest that PSII is weakly affected by the imposed osmotic stress. The fluorescence behaviour of the examined cultivars is related to their RWC.
Asunto(s)
Permeabilidad de la Membrana Celular/fisiología , Clorofila/metabolismo , Clorofila/efectos de la radiación , Hordeum/fisiología , Estrés Oxidativo/fisiología , Hojas de la Planta/fisiología , Agua/metabolismo , Membrana Celular/efectos de los fármacos , Membrana Celular/fisiología , Permeabilidad de la Membrana Celular/efectos de los fármacos , Desastres , Fluorescencia , Hordeum/efectos de los fármacos , Hordeum/efectos de la radiación , Inmunidad Innata/efectos de los fármacos , Inmunidad Innata/fisiología , Inmunidad Innata/efectos de la radiación , Luz , Presión Osmótica/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Enfermedades de las Plantas/inducido químicamente , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/efectos de la radiación , Polietilenglicoles/farmacología , Equilibrio Hidroelectrolítico/efectos de los fármacos , Equilibrio Hidroelectrolítico/fisiologíaRESUMEN
Monoclonal antibody (MAb) 8aC10 against Salmonella O:5 antigen was obtained after immunization of BALB/c mice with live attenuated mutant of Salmonella typhimurium. Antigen specificity of the MAb was characterized by ELISA, immunoblotting, passive hemagglutination (PHA), passive hemolysis and agglutination tests. In ELISA, PHA and immunoblotting the MAb reacted only with lipopolysaccharides (LPS) of Salmonella strains from group O:4 (B), expressing O:5 antigen. The MAb agglutinated in addition Salmonella strains with O:8 antigen from group C(2)-C(3) but did not react with purified LPS. These results demonstrate O:5 specificity of MAb 8aC10. Cross-agglutination with group C(2)-C(3) suggests the presence of similar but not identical epitope in O:8 expressing strains, which is possibly localized onto O-acetyl-abequose and abequose residues bound with a alpha-1-->3 linkage to the basic polysaccharide backbone of Salmonella LPS with O:5 and O:8 antigen respectively.
