The genetic basis of stem cell specification in somatic embryogenesis and organogenesis is still obscure. SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE (SERK) genes are involved in embryogenesis and organogenesis in numerous species. In vitro culture of Cyclamen persicum immature ovules provides a system for investigating stem cell formation and maintenance, because lines forming either organs or embryos or callus without organs/embryos are available for the same cultivar and plant growth regulator conditions. The present aim was to exploit this property of cyclamen cultures to understand the role of SERK(s) in stem cell formation and maintenance in somatic embryogenesis and organogenesis in vitro, in comparison with expression in planta. CpSERK1 and CpSERK2 were isolated from embryogenic callus. CpSERK1 and CpSERK2 levels by RT-PCR showed that expression is high in embryogenic, moderate in organogenic, and null in recalcitrant calli. in situ hybridizations showed that the expression of both genes started in clumps of pluripotent stem cells, from which both pre-embryogenic aggregates and organ meristemoids derived, and continued in their trans-amplifying, meristem-like, derivatives. Expression declined in organ meristemoids, in parallel with a partial loss of meristematization. In mature somatic embryos, and in shoot and root primordia, CpSERK1 and CpSERK2 were expressed in meristems, and similar patterns occurred in zygotic embryo and primary meristems in planta. The results point to SERK1 and SERK2 as markers of pluripotency in cyclamen. It is proposed that the high expression of these genes in the trans-amplifying derivatives of the stem cells maintains a pluripotent condition leading to totipotency and, consequently, somatic embryogenesis.

Pinus patula Schiede et Deppe is one of the most important softwood species for pulp production by the South African forestry industry. This study was aimed at developing a protocol for the genetic transformation of Pinus patula embryogenic tissue. This was achieved via the introduction of a bar-GUS cassette under the control of the ubiquitin promoter, through biolistic transfer. A stepwise selection was obtained using MSG3 maintenance medium supplemented with BASTAÒ herbicide at 1 mg l À1 followed by 3 mg l À1 active ingredient. Transgene delivery was more efficient when the medium was supplemented with 0.25 M sorbitol. Expression of positive histochemical GUS activity in embryonal heads was observed. Positive PCR analysis of both GUS and bar transgenes (40% and 47% transformation efficiency, respectively) indicated successful genetic modification of P. patula embryonal suspensor masses by the pAHC25 plasmid. This indicates that P. patula is amenable to gene transfer.

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The natural occurrence of ochratoxin A (OTA) and cis- and trans-resveratrols in red wines has been widely reported. The aim of this work was to evaluate the ochratoxin A (OTA) and both cis- and trans-resveratrol content of red wine (from must to wine) in a pilot-scale vinification process in Calabria (Italy). Eleven samples were collected at different stages of vinification and analysis was carried out by HPLC. Wine from manufacturer 3 contained the highest amount of trans-resveratrol (3.41 mg l(-1)). This wine was characterized by an Aglianico-Magliocco grape variety. Interestingly, data regarding OTA showed that the value of this contaminant was low in all analyzed samples and, in each case, below the legal limit (2.0 mg l(-1) (ppb)). Overall, the results demonstrated the high quality of wines produced in Calabria.

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