| Pepper (Capsium annuum L.) is one of the most important and popular vegetable crops around the world . However, productivity and quality are greatly affected by pathogen attack, although improving its resistance has been studied for long time. It is laborious and slow to create a new cultivar with high-multi resistance and high yield and quality through conventional breeding methods from present germ-plasm. A well-characterized plant defense response associated with pathogen attack is the expression of pathogenesis-related (PR) genes. One strategy to improve disease resistance in crop plant is by over-expressing anti-microbial proteins such as PR proteins. However, expression of individual PR genes has only led to a partial tolerance to several fungal pathogens. In systemic acquired resistance, a large number of PR genes are coordinately expressed and this type of resistance is known to be effective against a wide range of pathogens. A more effective approach to engineer crop plants with enhanced protection against pathogens might be to coordinately express a large combination of PR proteins in the plant. However, transferring multiple genes into a plant is technically difficult. Transferring gene encoding transcription factor into crop plants may provide a new approach to improving crop plants with enhanced PR gene expression and disease resistance. Development of plant genetic engineering technology provides new strategies and strong tools for genetic improvement of crops. Transgenic technology has been successfully used on over 200 plants. A little success have made on pepper genetic engineering within 10 years, The recombinant DNA manipulation of pepper, however, has been hindered by difficulty in regenerating whole plants from tissue culture and in obtaining transformed pepper tissue and ultimately in linking regeneration with transformation. Therefore, it would be desirable to set up an efficient method for the recombinant DNA transformation of pepper plant material and the regeneration of whole plants. In this studies, 'Zhongjiao 5' sweet pepper and 'Xiangyan 10' hot pepper were used as experimental materials. The effect of concentrations and combinations of 6-BA and IAA, concentrations of PA and ABA on adventitious bud differentiation and elongation from cotyledon explants had been systematic studied. High efficient cotyledon regeneration system had been established. On the base of this work, The effects of pH value of Agrobacterium solution, AS concentration in co-cultivation medium, temperature during co-cultivation and days for co-cultivation on transformation efficiency were studied by using green fluorescent protein gene as report gene. Consequently, an effective and stable transformation system had been established.The novel JERFs gene(JERF10, JERF26, JERF33, JERF36) which were isolated from tomato cDNA expression library and encode transcription factors that belong to ERF family were successfully transferred into young cotyledon of 'Zhongjiao 5' sweet pepper and 'Xiangyan 10' hot pepper by using the fore-mentioned system. The transgenic pepper plant which disease resistance capability increased significantly was selected out from the regeneration plants by kanamycin,Southern blotting and Northern blotting.The main results are following:1.100 u mol/L PA added during differentiation and elongation stage and 0.3mg/L ABA added during differentiation stage improved the elongation rate of adventitious bud. A high efficient regeneration system for cotyledon was established. The high efficient media for cotyledon differentiation was consist of MB+6-BA3.5 ~ 5.0mg/L+IAA0.5 ~ 1.0mg/L+PA(Spd,Spm)75 ~ 100 u mol/L+ ABA0.3mg/L+AgNo35.0mg/L+sugar3%+ agar0.7%; The high efficient media for adventitious bud elogation was consist of MB + 6-BA0.9mg/L + IAA0.3mg/L + PA 100 u mol/L +AgNo35.0mg/L+sugar3%+agar 0.7%. 2.When pH value of Agrobacterium solution is 5.2, transformation efficiency of cotyledon incubated on co-cultivation medium added 200 u M AS increased significantly under 23 C and 5 days dark co-cultiva...
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