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Salinity and drought are significant abiotic stresses causing a considerable loss of seed and biomass yield in most commercial crops. Some of the most critical players in the abscisic acid pathway are drought responsive element binding (DREB) proteins that are a part of AP2/ethylene response factor transcription factors that bind to promoters of some family genes needed to be expressed under abiotic stresses. In this study, salt‐ and drought‐tolerant maize plants were produced from immature maize embryos bombarded by the sorghum (Sorghum bicolor L.) DREB2 gene that is linked to hygromycin resistance (hpt) genes. The putative transgenic calli were transferred to an N6 medium containing 1 mg/L benzylaminopurine and 50 mg/L hygromycin. Regeneration was completed after 4 weeks on selective media under a 16/8 h light/dark condition at 25°C. Polymerase chain reaction (PCR) and reverse transcription‐PCR approved the existence of upstream promoter (rd29a), hpt gene, and the expression of the DREB2 in transgenes up to the third generation (T2). It was found that the K+/Na+ ratio and the amount of proline as a screening indicator were higher in transgenic plants compared to their wild types. This result is a promising model to enhance maize tolerance to abiotic stressors. [ABSTRACT FROM AUTHOR]

In most procedures that involve gene cloning, after the amplification of a target gene by PCR or by Real-time PCR, the purification of the trapped gene on agarose gel is a crucial stage. There are various methods for extracting genes from agarose gel by removing other contaminants. We isolated the amplified PqHMGR gene (derived from Ginseng (Panax quinquefolius)) from agarose gel by a quasi-electrophoresis device (similar to electro-elution technique). Moreover, the efficiency of this new approach was compared with that of the commercial kit 'Silica Bead DNA Gel Extraction' (Thermo Scientific American Company). Ligation to the PTG- 19 plasmid and cloning in E. coli bacteria were also done. The results showed successful isolations of targeted DNA, along with a high efficiency in producing recombinant DNA and in concluding a successful cloning procedure through this new device. The invented method provided a better purification ability than the commercial kit, but because of using the TAE 1X buffer as the purified gene storage solution, the plasmid and bacterial transformation rates were slower than the commercial kit method. It was found that using the new method for the purification of nucleotide sequences by electrophoresis and electrophoresis buffer is feasible, and that these purified fragments can be applied in cloning and sequencing. Using the TAE 1X buffer instead of distilled water did not cause problems in gene binding to PTG-19 plasmid. It also allowed a successful transformation of E. coli bacteria by the modified plasmid. Nonetheless, using TAE 1X buffer reduced the modification rate of the PTG-19 plasmid and decreased the rate of E. coli transformation by the modified plasmid. [ABSTRACT FROM AUTHOR]