| Autor: |
B. S. Sangwan, Rajbir S. Sangwan, T. Tetu |
| Rok vydání: |
1990 |
| Předmět: |
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| Zdroj: |
The Impact of Biotechnology on Agriculture ISBN: 9789401067522 |
| DOI: |
10.1007/978-94-009-0587-0_12 |
| Popis: |
Different systems of plantlet regeneration via somatic embryogenesis or organogenesis in sugarbeet (i), soybean (ii) and pea (iii) tissue cultures have been described. Organogenic sugarbeet calli were obtained preferentially from inflorescence apices with an association of zeatin and triiodobenzoic acid. Somatic embryogenesis from calli or from primary explants needed multiple hormonal sequences and depended from the genotypes used. The liquid consistency of the endosperm was used as a marker for screening the convenient embryogenic zygotic embryos. Interactions between the two morphogenic pathways; i.e, organogenesis and somatic embryogenesis have been scored. Incompletion of the somatic embryos lead to morphogenic developmental phases identical to those observed during adventitious buds formation. However, factors controlling the development of somatic embryos could not be completly elucidated. Scanning electron microscope studies showed the presence of numerous hair cells in the original adventitious buds but not in the dormant somatic embryos. On the contrary, ultrastructural observations revealed a large amount of protein bodies in the embryogenic calli, but not in the organogenic ones. In soybean and pea, direct adventitious somatic embryos were initiated from cultured immature zygotic embryos on Picloram and/or NAA suplemented media. Embryogenic capacity was significantly influenced by genotypes and sizes of the immature embryos at the time of culture. The effect of subculture frequencies were also investigated. Somatic embryos were transferred sequentially to different media until germination. Normal development and elongation was enhanced by reducing the auxin level and by increasing the nitrate level in the germination medium. Finally, these different regeneration systems are discussed as a prerogative for the production of transgenic plants in these three crop plants. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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