| Cotton (Gossypium hirsutum L.) is an important industrial crop. However, it has been proved to be difficult to manipulate in somatic cell culture system. In this research, culture method was optimized by different factor treatments, somatic embryos and regenerated plants were obtained of Jimian 7 and Jimian 14. The analysis of SDS-PAGE had been conducted with protein solutions extracted from embryogenic and nonembryogenic callus lines of Chuanmian 239. Moreover, phenotype variations of plantlets from somatic embryo and regenerated plants had been observed of Jimian 7, Jimian 14 and Chuanmian 239. The structures of shoot apexs of wild-type plants and abnormal plantlets of Chuanmian 239 had been compared with paraffin slice method. Several abnormal plantlets had been contrasted with mutants of apical-basal pattern formation of Arabidopsis. The main results are as follows:1. Induction of callus and embryogenic callusWhen cultured on MSB medium containing IAA0.5mg/L+KT0.1mg/L or ZT0.1mg/L~1.0mg/L, obvious difference among all the varieties was observed during callus induction and the difference was similar. Induction rate of callus for Jimian 7 and Jimian 14 was 78.2%~95.2%, for Yumian 1, Jia 39, MP4 and Lumian 15 was 47.6%~61.7%. For Jimian 7 and Jimian 14, the callus had induced embryogenic callus after subculture on MSB medium containing lAAO.lmg/L and KT0.1mg/L. For Lumian 15, embryogenic callus had not been induced. For the regenerated plant of Jimian 14, embryogenic callus and somatic embryos had been obtained even before subculture.2. Abilities of somatic embryogenesis of embryogenic callus and regenerationWhen subcuttured on MSB containing IAA0.1mg/L+KTO.lmg/L and KT0.1mg/L+KNO31.9g/L alternatively, the embryogenic callus kept its ability of embryogenesis. But with the time of culture and times of subculture during long-term subculture, the capabilities of embryogenesis and regeneration were decreased.3. Addition of hormone in suspension cultureOn suspension medium with NAA2mg/L~3mg/L, the cultures scattered better before subculture and more after subculture. In addition, the cuhures increased before maturation cultureand proliferation was quick after that. When 2mg/L NAA was added, there were a small number of embryoids and a lot of embryogenic callus.4. Rooting of plantlets from somatic embryoFor rooting of plantlets from somatic embryo, the liquid medium 1/2MSB with vermiculite was better than the solid medium 1/2MSB with 0.1% active carbon or free. When liquid medium 1/2MSB with vermiculite was used, rooting rate of plantlets was high (89%), the rooted seedlings were strong and easy to be transplanted to the field.5. SDS-PAGE of proteins of callusSDS-PAGE analysis of the protein solutions extracted from four callus lines showed that the expression of proteins of embryogenic callus line was different from that of nonembryogenic callus line, and there was difference among embryogenic callus lines with different ability of embryogenesis.6. Variations of plantlets from somatic embryo and regenerated plantsVariation of plantlets from somatic embryo was rich in type. There were two kinds of two-pole-root and apical-cup-shaped-true-leaf abnormal plantlets which had not been reported before. During long-term subculture, with the time of culture the quantity of the abnormal plantlets and variation frequency of plantlets both were increased. The highest rate was over 90%.The variations of plant shape, leaf and fertility were most in extensive variation characters of regenerated plants. Some plants were sterile or part-sterile in the early period, but with the time of growth duration, the sterility was transferred into normal, while others not. The variation frequency of regenerated plants increased with the time of culture.7. Comparison of microstructures between wild-type plants and abnormal plantletsAfter paraffin slice, there were different microstructures between shoot apexs of wild-type plants and abnormal plantlets. Wild-type plants had growth cone, leaf pr...
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