Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 7/25/2005
Publication Date: 3/31/2004
Citation: Mcphee, K.E., Gollasch, S., Schroeder, H.E., Higgins, T. 2004. Gene technology in pea. In: Curtis, I.S., editor. Transgenic Crops of the World - Essential Protocols. The Netherlands: Kluwer. p. 351-359. Interpretive Summary: Gene technology methods have been developed for a number of crops to introduce novel genes into plants and alter gene expression to facilitate the study of gene function. Use of Agrobacterium tumefaciens as a means of gene transfer in pea has proven effective, but suffers from low efficiency and extensive time and labor requirements to regenerate transformed plants. Methodology developed in the early 1990s is repeatable and has been adopted and modified only slightly in laboratories worldwide. Details of this methodology are described. Gene technology is a powerful tool in the study of gene function and can be used to introduce novel genes to improve crop adaptation to adverse environmental conditions as well as improve quality characteristics of the crop.
Technical Abstract: Gene technology or genetic transformation is a powerful method to introduce novel genes and study gene function and expression in plants. Grain legumes including pea, lentil, lupin, chickpea and faba bean are recalcitrant to regeneration in tissue culture resulting in poor efficiency in genetic transformation. Gene introduction using the natural DNA transfer mechanism of Agrobacterium tumefaciens has proven to be the most effective method for these crops, especially pea. Despite its effectiveness it is relatively inefficient and requires a long period of tissue culture to identify positive transformants. Thin slices of the imature embryonic axis are used as explants and are co-cultivated for seventy-two hours with A. tumefaciens to facilitate gene transfer. The explants are then placed on appropriate media to select against A. tumefaciens and for the presence and expression of the gene. Iterative cycles of transfer on selective media for approximately seven months are required to identify individual shoots stably expressing the gene. Transformed shoots are then transferred to the greenhouse by grafting onto a root stock and allowed to grow and produce seed. Although the method is laborious and time consuming it is repeatable and is used in several laboratories worldwide. The ability to alter gene function in plants promises to increase knowledge of gene function and allow development of crops with improved agronomic and quality characteristics.