Developing insect resistance with fusion gene transformation of chitinase and scorpion toxin gene in maize (Zea mays L)

Transgenic plants with introduced pest-resistant genes provide an efficient alternative insect control. A binary insect-resistant gene combination, containing an insect-specific chitinase gene (chi) and a scorpion insect toxin gene (Bmk), was introduced into a maize cultivar via pollen-mediated transformation. Thirty-eight putative trans- genic plantlets with kanamycin-resistance were obtained. Transgenic statuses of plants were confirmed by South- ern blot analysis. Bioassay by inoculation of Asian corn borer (Ostrinia furnacalis Guenée; ACB) larvae indicated that the degree of ACB resistance varied among the transgenic plants. The highest average calibrated mortality of larvae was approximately 67%. The genetic analysis of T1 progeny confirmed that the inheritance of introduced genes followed the Mendelian’s rules

Comparison between transgenic maize with exotic betaine aldehyde dehydrogenase (BADH) gene and its untransformed counterpart

We investigated the performance of a transgenic maize (Zea mays L) line with an exotic betaine aldehyde dehydrogenase (BADH) gene and its untransformed counterpart under drought and normal water conditions. Membrane permeability, osmoprotectant contents, and antioxidant enzyme activities of the maize lines as well as plant height and biomass were compared. The results showed that, under drought stress, compared with the untransgenic line, the contents of glycine betaine (GB), soluble sugars, soluble proteins and proline of the trans- genic line were significantly higher, so was the peroxidase (POD) activity; the contents of superoxide anion free radical, malondialdehyde (MDA) and the electrical conductivity of the transgenic line were lower; plant height and the biomass of the transgenic line were significantly higher. Under normal water conditions, the contents of soluble protein and MDA content of the transgenic line were significantly lower; but it was not the case for the content of superoxide anion free radical, electrical conductivity and superoxide dismutase (SOD) activity. No significant difference was observed in GB content and, the plant height and the biomass between the 2 lines. We conclude that the transgenic maize with exotic BADH gene was superior over its untransformed counterpart under drought stress and they performed similarly under normal water conditions

Effects of transgenic poplar leaves with binary insect-resistance genes used as feed for rabbits

[EN] The aim of this work was to explore the potential toxicological effects on rabbits of transgenic poplar (Populus cathayana Rehd.) leaves with binary insect-resistance genes used as feed. Fifty-four 40-d-old weaned New Zealand White Rabbits (Oryctolagus cuniculus) (live weight 0.98±0.1 kg) were fed for 70 consecutive days with a common pelleted diet and fresh poplar leaves containing a chitinase-BmkIT gene combination or untransformed counterparts (60 g/d). Rabbit body weight and hematological and biochemical data in blood samples were recorded. Organ histological structures were observed and the organ weights in the 2 groups were also measured. The results of the growth study revealed no significant differences (P>0.05) for final mean BW of rabbits, intake of the combined feed and poplar leaves or feed conversion ratio between the 2 groups. No obvious pathological changes were observed in the small intestine, stomach, spleen, kidney, lung, heart, bladder, pancreas, prostate and ovary. Electron microscopic observation of liver cells and renal cells showed they were both normal in the 2 groups. All hematological and biochemical data tested fell within the normal range in the 2 groups after 70 d of feeding. We conclude that the poplar leaves with the chitinase-BmkIT gene combination had no obvious harmful effects on rabbits.The research was supported by the grants of NSFC (31240081), Major Projects for Transgenic Organism Breeding from Chinese Ministry of Agriculture (2013ZX08003-001), Scientific and Technological Project from Shanxi Science and Technology Department (20110311009) and Shanxi Scholarship Council of the People's Republic of China (2011-061).Yang, L.; Sun, Y.; Hao, Y.; Wang, Y. (2013). Effects of transgenic poplar leaves with binary insect-resistance genes used as feed for rabbits. World Rabbit Science. 21(4):257-261. https://doi.org/10.4995/wrs.2013.1188SWORD25726121

Expression of Foreign Genes Demonstrates the Effectiveness of Pollen-Mediated Transformation in Zea mays

Plant genetic transformation has arguably been the core of plant improvement in recent decades. Efforts have been made to develop in planta transformation systems due to the limitations present in the tissue-culture-based methods. Herein, we report an improved in planta transformation system, and provide the evidence of reporter gene expression in pollen tube, embryos and stable transgenicity of the plants following pollen-mediated plant transformation with optimized sonication treatment of pollen. The results showed that the aeration at 4°C treatment of pollen grains in sucrose prior to sonication significantly improved the pollen viability leading to improved kernel set and transformation efficiency. Scanning electron microscopy observation revealed that the removal of operculum covering pollen pore by ultrasonication might be one of the reasons for the pollen grains to become competent for transformation. Evidences have shown that the eGfp gene was expressed in the pollen tube and embryos, and the Cry1Ac gene was detected in the subsequent T₁ and T₂ progenies, suggesting the successful transfer of the foreign genes to the recipient plants. The Southern blot analysis of Cry1Ac gene in T₂ progenies and PCR-identified Apr gene segregation in T₂ seedlings confirmed the stable inheritance of the transgene. The outcome illustrated that the pollen-mediated genetic transformation system can be widely applied in the plant improvement programs with apparent advantages over tissue-culture-based transformation methods