In attempt to improve salt tolerance of alfalfa (Medicago sativa L.) plants, a soybean DREB orthologue, GmDREB1, was introduced into alfalfa plants under the control of Arabidopsis Rd29A promoter. Its incorporation and expression in transgenic plants were confirmed by DNA and RNA gel-blot analyses. The level of salt tolerance of transgenic lines was significantly higher than that of wild-type control plants as measured by ion leakage, chlorophyll fluorescence value, contents of free proline and total soluble sugars. Moreover, northern blot analysis revealed that the transcript level of D1-pyrroline-5-carboxylate synthase (P5CS) was up-regulated in the transgenic plants. These results suggested that the stressinducible expression of GmDREB1 conferred salt tolerance in transgenic alfalfa plants. In addition, no visible phenotypic alternations were observed in the transgenic plants due to the use of stress-inducible Rd29A promoter. It was the first to describe transgenic expression of DREB genes in alfalfa and these transgenic lines with high salt-tolerance are of significance in the forage breeding.

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A putative vacuolar Na + /H + antiporter gene (SsNHX1) was isolated from the halophyte Salsola soda using the rapid amplification of cDNA ends method. Highly conserved regions of plant vacuolar Na + /H + antiporter, including amiloride-binding domain, NHE (Na + /H + exchange) domain, and 12 transmembrane segments, were found in the deduced amino acid sequence of SsNHX1. Multiple alignments of vacuolar Na + /H + antiporters showed that SsNHX1 shared high identity with other plant vacuolar Na + /H + antiporters. Phylogenetic relationship analysis indicated that SsNHX1 was clustered into the vacuolar Na + /H + antiporter group. Taken together, these results suggest that SsNHX1 is a new member of the vacuolar Na + /H + antiporter family. The effective expression of SsNHX1 in alfalfa (Medicago sativa L.) enhanced the salt tolerance of transgenic alfalfa which could grow in high concentrations of NaCl (up to 400 mM) over 50 days. This was the highest level of salt tolerance reported in transgenic plants. A further analysis of the physiological characteristics of transgenic and wild-type plants, including the Na + and K + contents, superoxide dismutase activity, the rate of electrolyte leakage, and the proline content, showed that large amounts of Na + in the cytoplasm of leaves were transported into vacuoles by the exogenous Na + /H + antiporter, which averted the toxic effects of Na + to the cell of transgenic alfalfa.

Urban planning has been widely applied as a regulatory measure to guide a city's construction and management. It represents official expectations on future population and economic growth and land use over the urban area. No doubt, significant variations often occur between planning schemes and actual development; in particular in China, the world's largest developing country experiencing rapid urbanization and industrialization. This in turn leads to difficulty in estimating the environmental consequences of the urban plan. Aiming to quantitatively analyze the uncertain environmental impacts of the urban plan's implementation, this article developed an integrated methodology combining a scenario analysis approach and a stochastic simulation technique for strategic environmental assessment (SEA). Based on industrial development scenarios, Monte Carlo sampling is applied to generate all possibilities of the spatial distribution of newly emerged industries. All related environmental consequences can be further estimated given the industrial distributions as input to environmental quality models. By applying a HSY algorithm, environmentally unacceptable urban growth, regarding both economic development and land use spatial layout, can be systematically identified, providing valuable information to urban planners and decision makers. A case study in Dalian Municipality, Northeast China, is used to illustrate applicability of this methodology. The impacts of Urban Development Plan for Dalian Municipality (2003-2020) (UDP) on atmospheric environment are also discussed in this article.

A hairpin RNA-encoding construct targeting gmFAD2-1 was transformed into soybean, and an optimised Agrobacterium-mediated embryonic tip system was employed. A novel intergeneric grafting method using transgenic plantlets as scions was used instead of the conventional rooting method. Compared with traditional acclimatisation, the survival ratio of cleft grafts increased by 70%, and the culture period was shortened by about 40 days. The regeneration frequency of the grafted shoots in this embryonic tip system was approximately 74.6%. Soybean transformants were confirmed by Southern and Northern blot hybridisation analyses. The fatty acid composition of the T 1 and T 2 seeds from the transformed plants was determined by gas chromatography. The resulting downregulation of the gmFAD2-1 gene substantially increased the level of oleic acid from 16% to 55% as indicated by the oleic desaturation proportion (ODP). The ratio of plants with high ODP, moderate ODP and low ODP was about 1:2:1, which was consistent with a singlegene segregation pattern.