| Pepper (Capsicum.annuum L.) is one of the most widely cultivated Capsicum species in subtropics and temperate countries. And also, it is one of the most vegetables playing very important role in social and economic life, which has the second cultivation area of all vegetables in China. The vulnerability of pepper genotypes to a multitude of abiotic and biotic stresses has restricted its yield badly. It costs too much time to get new species which have good adaptability only by conventional plant breeding. And, there are certain limitations to this technology due to the limited gene pool. Hence, it has a high value in research and application of the genetic transforming biotechniques encompassing plant in vitro culture. In detail, it can be to the point to overcome the obstacles of gene transferring between varieties, and so the genetic transforming biotechniques encompassing plant in vitro culture can help us get new species with modified characters. As a result, a stable and effective regeneration system is the prerequisite of genetic transformation. Pepper has been hard to regenerate because of its recalcitrance in vitro culture as compared to other solanaceous crops like tobacco, tomato, potato. The organogenesis and somatic embroyogenesis are two ways of pepper plants’ regeneration, and the organogenesis way is the normal one. Series of factors affect the regeneration of pepper plants, especialy the type and concentration of the additives, which has few research reports of the effects as well as the interaction effects of the additives. And in orthogonal design, different combinations of various factors are arranged according the standard orthogonal table, optimized combinations can be found with shorter time and less test cycles by orthogonal test analysis of the results. In these experiments, sweet pepper LUOJIAOJIUHAO and hot pepper QIANJIAOWUHAO were used as plant materials. After the best type of explants for regeneration were found by pretests, the effects and interaction effects of BA,IAA,AgNO3,GA3as additives were studied on the differentiation of explants and elongation of shoots. With analysis of the orthogonal tests results, the best combinations of additives for explants differentiation and shoots elongation were found. Sequencely, regenerated plants were obtained after rooting tests, furthermore a regeneration system was established. Observation of the organogenesis process in cytohistology was taken in the regeneration system, and some differences in organogenesis process between the sweet pepper and hot pepper were obtained. The main results are listed as follows,1. Cotyledon-petiole was the best explants for pepper in vitro regeneration.2. For differentiation of the cotyledon-petiole explants of QIANJIAOWUHAO, the best combination of additives was given by BA6.0mg/L+IAA1.0mg/L+AgNO35.0mg/L with differentiation rate at81.18%. And the effects and the interaction effects of the additives were ranked as BA×IAA>BA> IAAxAgNO3> BA×AgNO3> IAA> AgNO3.3. For differentiation of the cotyledon-petiole explants of LUOJIAOJIUHAO, the best combination of additives was given by BA5.0mg/L+IAA0.5mg/L+AgNO35.0mg/L with differentiation rate at94.74%. And the effects and the interaction effects of the additives were ranked as AgNO3> BA> BA×IAA> IAA×AgNO3> BA×AgNO3> IAA.4. For shoot elongation of QIANJIAOWUHAO, the best combination of additives was given by BA3.0mg/L+IAA0.5mg/L+GA31.0mg/L+AgNO30mg/L with SEC(Shoot Elongation Capacity) at47.52%. And the effects and the interaction effects of the additives wer ranked as AgNO3>IAA×GA3>BA×IAA>IAA>BA×GA3>GA3>BA.(SEC=average elongated shoots nuberx shoot elongation rate)5. For shoot elongation of LUOJIAOJIUHAO, the best combination of additives was given by BA3.0mg/L+IAA1.0mg/L+GA32.0mg/L+AgNO30mg/L with SEC at19.35%. And the effects and the interaction effects of the additives were ranked as BA×IAA> IAA>BA>AgNO3>GA3>IAA×GA3>BA×GA3.6. For shoot rooting, the optimal medium was MS+sucrose30.0g/L.7. The organogenesis of the two types of pepper came from the exogenous origin.8. For QIANJIAOWUHAO and LUOJIAOJIUHAO explants, the organogenesis processes were similar. After the vascular bundles and the parenchyma started to divide in row, vascular nodules and meristem nodules formed.9. The vascular bundles of LUOJIAOJIUHAO explants started to divide after3days’ culture which was earlier than that of QIANJIAOWUHAO explants’vascular explants which took6days’culture.10. For LUOJIAOJIUHAO, great proliferation of unembryonic callus were found with suborbicular, similar in size and closely packed cells, while QIANJIAOWUHAO not. |
PDF Full Text Request