Dataset Information

Improved efficiency of doubled haploid generation in hexaploid triticale by in vitro chromosome doubling.

ABSTRACT:

Background

Doubled haploid production is a key technology in triticale research and breeding. A critical component of this method depends on chromosome doubling, which is traditionally achieved by in vivo treatment of seedlings with colchicine.

Results

In this study we investigated the applicability of an in vitro approach for chromosome doubling based on microspore culture. Our results show a pronounced increase in the proportion of doubled haploid triticale plants compared to the spontaneous doubling rate, but also compared to the doubling obtained by the standard in vivo approach. In addition, the frequency of plants surviving from culture medium to maturity is also much higher for the in vitro approach. Colchicine concentrations of 1?mM for 24?h or 0.3?mM applied for 48 or 72?h during the first hours of microspore culture performed best.

Conclusions

Our results suggest that for triticale, in vitro chromosome doubling is a promising alternative to the in vivo approach.

SUBMITTER: Wurschum T

PROVIDER: S-EPMC3443072 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Publications

Improved efficiency of doubled haploid generation in hexaploid triticale by in vitro chromosome doubling.

Würschum Tobias T Tucker Matthew R MR Reif Jochen C JC Maurer Hans Peter HP

BMC plant biology 20120718

<h4>Background</h4>Doubled haploid production is a key technology in triticale research and breeding. A critical component of this method depends on chromosome doubling, which is traditionally achieved by in vivo treatment of seedlings with colchicine.<h4>Results</h4>In this study we investigated the applicability of an in vitro approach for chromosome doubling based on microspore culture. Our results show a pronounced increase in the proportion of doubled haploid triticale plants compared to th ...[more]

PMID: 22809089

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Project description:The use of doubled haploids in onion breeding is limited due to the low gynogenesis efficiency of this species. Gynogenesis capacity from Spanish germplasm, including the sweet cultivar Fuentes de Ebro, the highly pungent landrace BGHZ1354 and the two Valenciana type commercial varieties Recas and Rita, was evaluated and optimized in this study. The OH-1 population, characterized by a high gynogenesis induction, was used as control. Growing conditions of the donor plants were tested with a one-step protocol and field plants produced a slightly higher percentage of embryogenesis induction than growth chamber plants. A one-step protocol was compared with a two-step protocol for embryogenesis induction. Spanish germplasm produced a 2-3 times higher percentage of embryogenesis with the two-step protocol, Recas showing the highest percentage (2.09%) and Fuentes de Ebro the lowest (0.53%). These percentages were significantly lower than those from the OH-1 population, with an average of 15% independently of the protocol used. The effect of different containers on plant regeneration was tested using both protocols. The highest percentage of acclimated plants was obtained with the two-step protocol in combination with Eco2box (70%), whereas the lowest percentage was observed with glass tubes in the two protocols (20-23%). Different amiprofos-methyl (APM) treatments were applied to embryos for chromosome doubling. A similar number of doubled haploid plants were recovered with 25 or 50 μM APM in liquid medium. However, the application of 25 μM in solid medium for 24 h produced the highest number of doubled haploid plants. Somatic regeneration from flower buds of haploid and mixoploid plants proved to be a successful approach for chromosome doubling, since diploid plants were obtained from the four regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their gynogenesis efficiency.

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Dataset Information

Improved efficiency of doubled haploid generation in hexaploid triticale by in vitro chromosome doubling.

Background

Results

Conclusions

Publications

Improved efficiency of doubled haploid generation in hexaploid triticale by in vitro chromosome doubling.

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