Somatic Embryogenesis for Conifer Seedling Production

The Biology of Scaling

Abstract

Conifer somatic embryogenesis has long been recognized as an advanced vegetative propagation technology. Somatic embryogenesis provides a platform for capturing and long-term preservation of elite genotypes and developing commercial scale-up systems for mass production of plants. Although, significant success has been reported in improving conifer somatic embryogenic protocols, little has been presented to describe the complexity of integrating in vitro (laboratory) and ex-vitro (greenhouse) programs for developing a commercial production system capable of delivering tens of millions of conifer somatic seedlings. This integration requires both programs to run in concert and produce propagules capable of surviving and growing under greenhouse conditions at very early stages. It also requires the integration of seedling development events to ensure the production of quality seedlings that meet needs of the forest restoration program.

This paper describes the importance of protocol optimization for scaling-up the in vitro and ex vitro programs. The ‘biology of scaling’ is discussed in view of plant cell, embryo, germinant and somatic seedling requirements throughout the program. Logistical issues related to protocol optimization and scale-up are addressed. Specific control points for monitoring and controlling the commercial process are presented. The importance of developing standard operating procedures, media batch records, and quality control systems are discussed. Ultimately, a fully integrated system capable of producing tens of millions of conifer somatic seedlings is presented.