Location: Peanut and Small Grains Research Unit
Title: Simple and efficient genetic transformation of sorghum using immature inflorescencesAuthor
CHOU, JUAN - Oklahoma State University | |
HUANG, JIAN - Oklahoma State University | |
Huang, Yinghua |
Submitted to: Acta Physiologiae Plantarum
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/2/2020 Publication Date: 2/27/2020 Citation: Chou, J., Huang, J., Huang, Y. 2020. Simple and efficient genetic transformation of sorghum using immature inflorescences. Acta Physiologiae Plantarum. 42:41. https://doi.org/10.1007/s11738-020-3023-6. DOI: https://doi.org/10.1007/s11738-020-3023-6 Interpretive Summary: Sorghum improvement are currently based on the traditional breeding methods, which has been successful in development genetic improved hybrids and cultivars. However, tradition breeding is often to slow to achieve certain breeding goals or is limited because some genetic traits may not available in sorghum. Our current research effort aimed at development of a new genetic transformation system for sorghum using immature inflorescences as the targets. Under this research project, immature inflorescences were collected the donor plants and cultured in vitro. Then the target tissues were transformed with a gene construct, pBI121, using Agrobacterium-mediated transformation system or gene gun (biolistic particle delivery system). The transformed tissues were regenerated in vitro, and subsequently transgenic plants were transplanted in soil. All resultant transgenic plants were normal in morphology and fully fertile, in which the desired gene was incorporated based on the molecular evidence. The method described here represents a simple and efficient method for transformation of sorghum that can speed up and facilitate the process of engineering new varieties of sorghum. Technical Abstract: Sorghum is an important cereal crop and has been grown in a wide range of environments throughout tropic, sub-tropic, and warm-temperate regions. Genetic improvement of sorghum has been based on the conventional breeding methods, but there is a limited application of genetic transformation for sorghum improvement due to its recalcitrance to genetic manipulation in vitro. The current study aimed at the development of immature inflorescences as a genetic transformation system for sorghum. Immature inflorescences of two sorghum elite lines were chosen as the explants for developing a new method for genetic transformation. Sorghum immature inflorescences (approx. 0.5–1.0 cm in length) were obtained from the donor plants and co-cultured with virulent Agrobacterium tumefaciens strain LBA4404 harboring a binary vector. Following co-cultivation, the explants were transferred to the regeneration medium with or without selection, where the resulting embryogenic callus was induced to form shoots and roots. This system was also amenable for gene gun (biolistic particle delivery system). Putatively transformed plants were confirmed the presence of transgene in the plants based on the molecular analysis of the T1 plants. All resulted transgenic plants were normal in morphology and fully fertile. The transformation system developed with the immature inflorescence is simple and efficient method for sorghum transformation, which can speed up the process of engineering new varieties of sorghum. |