Bioreactors and Automation in Date Palm Micropropagation

Researchers have successfully micropropagated several cultivars of date palm (Phoenix dactylifera L.) using in vitro tissue culture techniques based on somatic embryogenesis and shoot organogenesis. However, major hindrances exist in scale-up including low productivity of cultures, synchronization of embryogenesis, conversion of matured somatic embryos, low multiplication rates of de novo shoots and high production cost of plantlets. Recently, tremendous success has been achieved in automation of micropropagation steps of many plant species using ­liquid culture systems. This achievement constitutes an alternative for resolving all the preceding problems. For example, yield of cotyledonary somatic embryos ­produced in suspension cultures were 17-fold greater than on agar-solidified medium. The transfer of shoot clusters in temporary immersion bioreactor clearly improved the yield of regenerated shoots 5.5-fold in comparison with that regenerated on agar-solidified medium. The aim of this chapter is to critically outline the potential of liquid culture systems (suspension culture and temporary immersion system, TIB) to large scale and automation of date palm micropropagation. The principles, advantages and disadvantages of these methods are also described.