Doubled haploid production in Brassica L. species

Abstract

The technology for the production of doubled haploids (DH technology) through in vitro anther or microspore cultures is one of a number of approaches to the genetic improvement of agricultural crops. Fully homozygous plants can be obtained within a year through the DH technology in contrast to conventional inbreeding methods, which may take from 6 to 12 years. In addition, this biotechnological approach provides benefits in terms of widening the formation process due to a gamete-clonal variation. The greatest success in the HD plant production through microspore cultures has been achieved in some varieties of rape (Brassica napus L.). The efficiency of the DH technology in the other Brassica species still remains low. A variety of factors, such as donor plant growth conditions, genotypes, microspore developmental stages, culture medium composition, and cultivation conditions can affect the efficiency of microspore embryogenesis induction. Microspore reprogramming from the gametophytic development to a sporophytic pathway takes place under various stress factors. Certain factors such as the pretreatments of anthers and microspores with a high temperature or colchicine seem to favor embryogenesis in the Brassica species. Plant regeneration from embryoids can be improved by proper application of growth regulators (ethylene, abscisic acid, and indoleacetic acid). The optimum value and the combination of these factors are decisive prerequisites for efficient embryogenesis. This survey article summarizes the experience of foreign and Russian scientists in developing the technology for the production of Brassica double haploids, as well as shows both the various factors affecting the DH plant production processes and the approaches allowing us to increase the induction of microspore embryogenesis in plants of the Brassica genus.