Current status and future prospects of large scale micropropagation in commercial plant production

Abstract

Currently 180–200 million plants are produced worldwide per year by tissue and cell culture techniques. Conventional plant production has been replaced by large scale micropropagation, highest in ornamentals, followed by fruit trees and small fruits, and to a smaller extent in vegetables and agricultural plants. The objectives are higher productivity, elimination of pathogens, rapid multiplication of new genotypes, selection of somaclonal and induced variants, preservation of germplasm and long‐term storage. The profitable application of in vitro methods requires the maintenance of high regeneration rates, but this can be limited by the decline of the organogenic competence, genetic instability, especially in callus cultures, and by vitrification phenomena. Regulation of organ differentiation on a cellular level is not fully explored. Some histological features and biochemical markers, such as specific proteins, indicate early steps of organogenesis. Optimally controlled bioreactors for somatic embryogenesis in suspension cultures are considered to be the most efficient system in commercial micropropagation. Agricultural plants, vegetables, fruit trees and small fruits with high economic importance in micropropagation and plant production are described.