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To characterise the effect of bacterial inoculants (Azospirillum brasilense and Pantoea dispersa) on the response of sweet pepper (Capsicum annuum L.) to saline stress, plants were exposed to 0, 40, 80 and 120 mM NaCl in solution. The effect on plant growth; leaf gas exchange; NO3–, Cl–, K+ and Na+ accumulation; and chlorophyll fluorescence and content were investigated. Total plant DW was reduced significantly by salinity but when inoculants were applied, DW was increased. Inoculated plants showed higher DW accumulation in the roots. Salinity levels up to 80 mM NaCl did not affect the net assimilation rate in inoculated plants but 40 mM NaCl was enough to reduce this parameter in non-inoculated plants. The leaf area ratio was not modified substantially by inoculation. The leaf Cl– concentration of inoculated plants was reduced at the highest salinity, compared with control plants, and NO3– concentration increased markedly. A higher K+ : Na+ ratio was found in inoculated plants. Leaf photosynthesis and stomatal conductance were impaired significantly at moderate, but not low, salinity, the effect of inoculation being enough to maintain higher stomatal conductance under higher stress. The photochemical efficiency of PSII and the relative chlorophyll content were not affected by the inoculants. Thus, the effects of the inoculants on the response to salinity were due mainly to stomatal regulation of photosynthesis rather than effects on biochemical limitations on photosynthesis. These results indicate the benefits of these bacterial inoculants in ameliorating the deleterious effect of NaCl in a salt-sensitive crop like sweet pepper.

Maintaining quality is of paramount importance in the postharvest period. This study shows the effect of both temperature and spraying treatments with regard to maintaining fruit quality during this period, and provides new insights into the physiological role of enzymes of the antioxidant system during pepper storage at low temperature.

We studied the effects of foliar application of urea or methyl-jasmonate (MeJA) on the salinity tolerance of broccoli plants (Brassisca oleracea L. var. italica). Plant dry weight, leaf CO 2 assimilation, and root respiration were reduced significantly under moderate saline stress (40 mM NaCl) but application of either urea or MeJA maintained growth, gas exchange parameters, and leaf N-NO 3 -concentrations at values similar to those of non-salinized plants. Additionally, when these two foliar treatments were applied leaf Na ? concentration was reduced compared with control plants grown at 40 mM NaCl. However, at a higher salt concentration (120 mM NaCl), no effect of the foliar applications was found on these parameters. Salinity also decreased leaf d 15 N but increased d 13 C. Our study shows the feasibility of using foliar urea or MeJA to improve tolerance under moderate saline stress.