Gene banking for ex situ conservation of plant genetic resources

Abstract

Seed storage is one of the most widespread and valuable ex situ approaches to conservation. Extensive expertise has been developed in this fi eld by agencies and institutions involved with plant genetic resources over the past 30 years. Seed banking has considerable advantages over other methods of ex situ conservation such as ease of storage, economy of space, relatively low labour demands and, consequently, the capacity to maintain large samples at an economically viable cost. Depending on the species, seeds are dried to suitably low moisture content according to an appropriate protocol. Typically this will be less than 5 %. The seeds then are stored at −18 °C or below. Because seed DNA degrades with time, the seeds need to be periodically replanted and fresh seeds collected for another round of long-term storage. There are about six million accessions, or samples of a particular population, stored as seeds in about 1,300 gene banks throughout the world as of 2006. The procedure for seed storage along with the latest development on gene banking is discussed in this chapter.