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Payam Pour Mohammadi Ahmad Moieni Asa Ebrahimi Farzad Javidfar 《Plant Cell, Tissue and Organ Culture》2012,108(2):251-256
An efficient method for producing doubled haploid plants of oilseed rape (Brassica
napus L.) was established using in vitro colchicine treatment of haploid embryos. Haploid embryos in the cotyledonary stage were
treated with one of four colchicine concentrations (125, 250, 500 and 1,000 mg/L); for one of three treatment durations (12,
24 and 36 h) at one of the two temperatures (8 and 25°C) and were compared to control embryos (without colchicine treatment).
The number of chromosomes, seed recovery, size and density of leaf stomata, and pollen grain size from regenerated plants
were determined. No doubled haploid plants were regenerated from control embryos; however, the doubled haploid plants were
regenerated from colchicine-treated embryos. A high doubling efficiency, 64.29 and 66.66% of regenerated plants, was obtained
from 250 mg/L colchicine treatment for 24 h and 500 mg/L colchicine treatment for 36 h, respectively, at 8°C. Following 500 mg/L
colchicine treatment for 36 h, a few plants regenerated (9 plants). At the higher colchicine concentration (1,000 mg/L), no
plant regenerated. These results indicate that the colchicine treatment of embryos derived from microspores can induce efficient
chromosome doubling for the production of doubled haploid lines of oilseed rape. 相似文献
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Rapeseed (Brassica napus L.), which is the third leading source of vegetable oil, is sensitive to drought stress during the early vegetative growth stage. To investigate the initial response of rapeseed to drought stress, changes in the protein expression profiles of drought-sensitive (RGS-003) and drought-tolerant lines (SLM-003), and their F1 hybrid, were analyzed using a proteomics approach. Seven-day-old rapeseed seedlings were treated with drought stress by restricting water for 7 days, and proteins were extracted from roots and separated by two-dimensional polyacrylamide gel electrophoresis. In the sensitive rapeseed line, 35 protein spots were differentially expressed under drought stress, and proteins related to metabolism, energy, disease/defense, and transport were decreased. In the tolerant line, 32 protein spots were differentially expressed under drought stress, and proteins involved in metabolism, disease/defense, and transport were increased, while energy-related proteins were decreased. Six protein spots in F1 hybrid were common among expressed proteins in the drought-sensitive and -tolerant lines. Notably, tubulin beta-2 and heat shock protein 70 were decreased in the drought-sensitive line and hybrid F1 plants, while jasmonate-inducible protein and 20S proteasome subunit PAF1 were increased in the F1 hybrids and drought-tolerant line. These results indicate that (1) V-type H+ ATPase, plasma-membrane associated cation-binding protein, HSP 90, and elongation factor EF-2 have a role in the drought tolerance of rapeseed; (2) The decreased levels of heat shock protein 70 and tubulin beta-2 in the drought-sensitive and hybrid F1 lines might explain the reduced growth of these lines in drought conditions. 相似文献
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In this study, the effects of carbon sources, abscisic acid (ABA) either alone or in combination with polyethylene glycol
(PEG) were evaluated on secondary embryo (SE) induction and maturation in rapeseed microspore-derived embryos (MDE) of cultivars
Global, PF704 and Option. Among various carbon sources tested (sucrose, glucose, fructose and sorbitol), the use of 0.3 M (300 mOsml−1) glucose and 0.2 M (200 mOsml−1) sorbitol in SE induction medium (for cultivars Global and PF704) and sorbitol at 0.2 and 0.3 M (200 and 300 mOsml−1, for cultivar Option), induced the highest secondary embryogenesis percentage (%SE). The highest number of SEs per each MDE
(SE/MDE) was observed with 0.2 M (200 mOsml−1) sorbitol in cultivar Global and with 0.3 M (300 mOsml−1) glucose in cultivars PF704 and Option. In another part of this study, the effect of different concentrations of ABA (0, 20, 40, 60, 80 and 100 μM) and
of a combined use of ABA (0 and 40 μM) and PEG 4000 or PEG 6000 at 15 g l−1 (3.75 and 2.5 mOsml−1, respectively) was examined on induction and maturation of SEs. In the first experiment, the use of ABA in SE induction medium
reduced the mean number of SE/MDE in the three studied cultivars, whereas use of 40–80 μM ABA in SE induction medium increased
the percentage of mature SEs in each cultivar. The combined use of PEG with or without ABA also reduced the mean number of
SE/MDE compared with control, but resulted in significant enhancement of the percentages of mature SEs for the three cultivars. 相似文献
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Glyphosate is a non-selective broad-spectrum herbicide that inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). This is a key enzyme in the aromatic amino acid biosynthesis pathway of microorganisms and plants. The manipulation of bacterial EPSPS gene in order to reduce its affinity for glyphosate, followed by its transfer to plants is one of the most effective approaches for the production of glyphosate-tolerant plants. In this study, we chose to focus on amino acid residues glycine96 and alanine183 of the E. coli (k12) EPSPS enzyme. These two amino acids are important residues for glyphosate binding. We used site directed mutagenesis (SDM) to induce point mutations in the E. coli EPSPS gene, in order to convert glycine96 to alanine (Gly96Ala) and alanine183 to threonine (Ala183Thr). After confirming the mutation by sequencing, the altered EPSPS gene was transferred to rapeseed (Brassica napus L.) via Agrobacterium-mediated transformation. The transformed explants were screened in shoot induction medium containing 25 mg L−1 kanamycin. Glyphosate tolerance was assayed in putative transgenic plants. Statistical analysis of data showed that there was a significant difference between the transgenic and control plants. It was observed that transgenic plants were resistant to glyphosate at a concentration of 10 mM whereas the non-transformed control plants were unable to survive 1 mM glyphosate. The presence and copy numbers of the transgene were confirmed with PCR and Southern blotting analysis, respectively. 相似文献
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Secondary embryogenesis from rapeseed microspore-derived embryos (MDEs) was studied in three Brassica napus L. cultivars Global, PF704 and Option. The best results in terms of secondary embryogenesis percentage obtained in cultures of Global and PF704 MDEs (75.88 and 65.97 %, respectively) and PF704 produced the highest number of secondary embryos per each primary embryo (14.91 ± 2.18). After optimization of physical parameters,
rapeseed hypocotyls of MDEs were bombarded with microcarriers coated with a plasmid containing GUS reporter gene. The highest
levels of transient GUS expression were obtained using bombardment with gold particles of 1.6 μm, at helium pressure of 9.3
MPa, a bombardment distance of 9 cm, chamber vacuum pressure of 7.1 × 10−6 kPa and single bombardment in bombardment medium containing 0.4 M mannitol. 相似文献
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