Embryogenic calli

These results suggest that embryogenic calli can be selected from a mixed population of calli since the yellowish compact callus generally shows high em-bryogenicity. The image analysis using Br(Y-W) proposed here is a useful tool for automatic selection of such calli in a plant factory [74]. 

Much effort is being put into developing a reliable transformation protocol for the oil palm. We are employing both direct DNA uptake and biolistic bombardment to achieve this. Transformation of various tissues, including pollens, young leaves and embryogenic calli, has been attempted. 

Imbrie-Milligan, C.W. Hodges, T.K. (1986). Microcallus formation from maize protoplasts prepared from embryogenic callus. Planta, 168, 395-401. 

Diosgenin (Fig. 4) is a steroid sapogenin produced by Dioscorea species. This natural product is used as a precursor for the commercial synthesis of medicinal steroids such as prednisolone, dexamethasone, norethisterone, and metenolone, among others. Microtuber-derived cell suspensions of Dioscorea doryophora were able to accumulate diosgenin at concentrations as high as 3.5% g dw. Embryogenic callus of Tribulus terrestris were also able to accumulate diosgenin (170.7 1.0 pg/g dw). ... 

Keywords. Plant cell culture, Micropropagation, Bioreactor design, Embryogenic callus, Hairy root, Image analysis, Plant factory... 

Embryogenic callus was also obtained from the non-transformed roots cultured with 0.5 mg/1 NAA, Fig. (62). Mikimopine, however, was only detected in the MAFF clones. Fig. (63). 

The transformed cells of P. somniferum easily formed somatic embryos instead of roots. MAFF clone 1, which was the most embryogenic, accumulated about 10-fold higher levels of morphinan alkaloids than did non-transformed embryogenic callus (Table 20). Williams and Ellis... 

The medicinal plant, ES was used as the model dicotyledonous plant for understanding the embryogenic callus induction and plant regeneration. The factors affecting embryogenic callus induction efficiency and plant regeneration potential would be presented here. 

From our summary, it was obvious that 2,4-D is critical for callus initiation and embryogenic callus formation in ES, particularly when combined with the supplement of TDZ. 

Embryogenic callus and plant regeneration of Aneurolepidium chinensis (Trin.) Kitag. Journal of JUin Agricultural University, Vol.l2, p>p. 1-5 ISSN 1000-5684... 

It is worth reminding ourselves of another definition concerning SE. According to Verdeil and co-workers (2007), the embryogenic callus is an undifferentiated, unorganised tissue enriched in embryogenic cells, and the embryogenic cell is a cell that requires no further external stimulus to produce a somatic embryo. 

Finer, J.J., Kriebel, H.B., and Becwar, M.R. (1989) Initiation of embryogenic callus and suspension cultures of easier white pine (Pinus strobus L.). Plant Cell Rep., 8 203-206. 

Table 1. Examples of media used for embryogenic callus in vitro initiation (Author s own modification )...

Nawrot - Chorabik, K (2008). Embryogenic callus induction and differentiation in silver fir Abies alba Mill.) tissue culture. Dendrobiology, Vol. 59, pp. 31 40. 

Fig. 4. An embryogenic structure derived from an embryogenic callus used as explant (A), developed an embryogenic callus (B) after 90 days of culture in medium 1. After transferring embryogenic callus to medium 11, callus with somatic embryos at different stages occurred. Piece of callus with pro-embryos (C), globular embryo (D), coleopHlar embryo (E) and germinating embryo (F). Bar= 1mm. Coleoptile [c], germinative pore [gp], pro-embryo [pro]...

The effect of the brassinosteroid 22(S), 23(S)-homobrassinolide on initial callus, embryogenic callus and somatic embryo formation in coconut plumule explants was tested. The explants were exposed (during a 3 or 7 d pre-culture) to different concentrations (0.01, 0.1,1, 2 and 4 pM) of the brassinosteroid. The explants responded favorably to the brassinosteroid increasing their capacity to form initial callus, embryogenic callus and somatic embryos. The largest amount of somatic embryos formed, 10.8 somatic embryos / explant, was obtained exposing the explants for 3 d to the brassinosteroid at 0.01 or 0.1 pM, whereas 3.8 somatic embryos / explant were obtained from untreated explants. Efficiency-wise the overall effect of HBr increases the total amoxmt of somatic embryos formed p>er explant 2.8 times (Azpeitia effll. 2003). 

Becerril, J. L. Chan, and L. C. Rodriguez-Zapata. 2011. Transient genetic transformation of embryogenic callus of Cocos nucifera L. Biologia. 66 (5) 790-800. 

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