Sunflower (Helianthus annuus L.)

Area of Science:

• Plant Biotechnology
• Genetics
• Agricultural Science

Background:

• Sunflower (Helianthus annuus L.) transformation is challenging, with existing protocols often proving inefficient or difficult to replicate.
• Recalcitrance in sunflower in vitro culture hinders genetic improvement efforts.

Purpose of the Study:

• To establish a routine and efficient Agrobacterium-mediated transformation system for sunflower.
• To develop a reliable selection method for transformed sunflower tissues.
• To demonstrate the utility of the protocol for introducing various genes and evaluating promoter activity.

Main Methods:

• Utilized mature HA89 genotype sunflower seeds and Agrobacterium tumefaciens EHA105 strain for gene delivery.
• Implemented kanamycin selection based on root development to identify transformed shoots, avoiding visual selection methods.
• Confirmed transgene integration and expression using RT-PCR and GUS reporter gene assays.

Main Results:

• Successfully established a routine transformation system for sunflower using accessible resources.
• The kanamycin selection method effectively identified transformed shoots, preventing the inclusion of non-transformed 'escapes'.
• Demonstrated successful incorporation and stable expression of reporter and agronomic genes, with inheritance confirmed to the T2 generation.

Conclusions:

• The developed protocol offers a robust and reproducible method for sunflower genetic transformation.
• This system simplifies the process, making genetic engineering of sunflowers more accessible for research and crop improvement.
• The protocol supports the evaluation of gene expression patterns and the development of transgenic sunflower lines with desirable traits.