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The inability to conserve cocoa (Theobroma cacao L.) germplasm via seed storage and the vulnerability of field collections make the establishment of cryopreserved genebanks for the crop a priority. An effective encapsulation-dehydration based cryopreservation system has been developed for cocoa but because the somatic embryos used for freezing arise after a protracted period of callus culture there is concern about maintenance of genetic fidelity during the process. Microsatellite markers for seven of the 10 cocoa linkage groups were used to screen a population of 189 primary somatic embryo-derived emblings and the 43 secondary somatic embryos they gave rise to. Of the primary somatic embryos, 38.1% exhibited polymorphic microsatellite profiles while for secondary somatic embryos the frequency was 23.3%. The same microsatellite markers used to screen another population of 44 secondary somatic embryos cryopreserved through encapsulation-dehydration revealed no polymorphisms. Scanning electron microscopy showed the secondary somatic embryos were derived from cotyledonary epidermal cells rather than callus. The influence of embryo ontogeny on somaclonal variation is discussed.

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An efficient micropropagation procedure via adventitious shoot proliferation was developed for Aglaonema using the popular red cultivar 'Lady Valentine. ' Aseptic culture was initiated by culturing stem nodal segments on Murashige and Skoog (MS) medium supplemented with 32 mg·l −1 gentamicin, 8 mg·l −1 tetracycline and 4 mg·l −1 chloramphenicol. The growth of the axillary buds performed the best when 10 mg·l −1 6-benzyladenine (BA) was incorporated into the medium, and neither gibberellic acid (GA 3 ) nor dark exposure could improve the elongation of the axillary shoots. The single stem nodal segments excised from the elongated shoots were treated with different combinations of α-naphthaleneacetic acid (NAA) and thidiazuron (TDZ) and an average of 10.9 adventitious shoots per stem segment was produced with 0.5 mg·l −1 NAA and 2 mg·l −1 TDZ. Small shoot clusters were subsequently incubated with different concentrations of BA and GA 3 and results showed that 0.5-5 mg·l −1 BA treatments were more effective for shoot proliferation and elongation than 0.5-1 mg·l −1 GA 3 treatments. The longest shoots (reaching 2.69 cm after three months) were obtained on medium containing 5 mg·l −1 BA. Up to 80% of the elongated shoots successfully rooted ex vitro with the application of 1 and 2 mg·l −1 indole-3-butyric acid (IBA) and 92.5% of these rooted shoots survived following transfer to the greenhouse.