Mitotic chromosome doubling of plant tissues in vitro

Abstract

In vitro chromosome doubling can be induced by several antimitotic agents. The most commonly used are colchicine, oryzalin and trifluralin. The process of induced chromosome doubling in vitro consists of a typical succession of sub-processes, including an induction phase and a confirmation protocol to measure the rate of success. The induction step depends on a large number of variables: media, antimitotic agents, explant types, exposure times and concentrations. Flow cytometry is the pre-eminent method for evaluation of the induced polyploidization. However, alternative confirmation methods, such as chromosome counts and morphological observations, are also used. Since polyploidization has many consequences for plant growth and development, chromosome doubling has been intensively studied over the years and has found its way to several applications in plant breeding. This review gives an overview of the common methods of chromosome doubling in vitro, the history of the technique, and progress made over the years. The applications of chromosome doubling in a broader context are also discussed.

Effects of Enhanced Ultraviolet-B Radiation on Chromosomes and Microtubule Arrays in Wheat Roots

“…Oryzalin, a microtubule inhibitor, blocks microtubule assembly but not ongoing disassembly, causing microtubule depolymerization. Oryzalin is used to induce chromosome doubling in plants by inhibiting mitotic activity and is considered a preferable alternative to colchicine because of its lower toxicity (Kermani et al, 2003;Dhooghe et al, 2011;Rêgo et al, 2011).…”

Colchicine and oryzalin effects on tetraploid induction and leaf anatomy of Solanum commersonii ssp.

“…This may have favored the occurrence of tetraploidy in the SCM 60 genotype (Table 1). Oryzalin has shown to be effective in the chromosome duplication in roses (ALLUM et al, 2007), and other fruit and ornamental plants (DHOOGHE et al, 2011).…”

“…The use of tetraploid plants, which was obtained by induced polyploidization in wild species of the genus Solanum, has been used as a means to transfer genes of agronomic interest from these species to cultivated potato (DHOOGHE et al, 2011). Obtaining tetraploid plants from SCM 60 clones (Table 1) is an important step, so that these plants can be employed in genetic breeding programs.…”

Autopolyploids in fodder grass breeding: induction and field performance

“…Colchicine was used in pioneering experiments, and it remained as a very popular antimitotic agent up to this day. Various tech-niques were developed to induce mitotic chromosome doubling in different plant species, including treatment of shoots, leaves, buds, node sections, embryos and cell suspension cultures (Dhooghe et al, 2011). Colchicine was proven to be very useful in most of these methods as well as in many plant species, however many researchers postulated the need for new antimitotic drugs as colchicine application is both hazardous due to its' toxicity, and costly, because high concentrations of colchicine are needed.…”