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Buttercup (Ranunculus asiaticus, family Ranunculaceae) hybrids are considered a popular and valuable ornamental crop in Europe and are cultivated both for cut flowers and for pot or border plants. In the Liguria region of northern Italy, Ranunculus hybrid cultivation has dramatically increased over recent years and the related sanitary issues regarding virus infection need to be carefully monitored in order to maintain commercial competitiveness. Presently, ELISA is the most used diagnostic tool for virus diagnosis, but if 'mother plants' with high economic value are to be tested, more sensitive molecular diagnostic tools are needed, together with efficient protocols for in vitro culture to eradicate viruses. In this study, new RT-PCR protocols were tested on virus-infected Ranunculus hybrid plants, indexed for the 13 most important Ranunculus-infecting viruses. Rapid, uniform and effective procedures for molecular diagnosis were devised in order to promote an easy technology transfer from scientific institutions to laboratories of small and medium private enterprises. Moreover, an in vitro culture procedure was established for this species, which proved to be extremely effective in virus eradication. Advanced technology and sustainable quality production of high economic value plants are keys for future competitiveness in floriculture.

Bituminaria bituminosa L. is known for producing several compounds with considerable pharmaceutical interest, such as phenylpropanoids, furanocoumarins and pterocarpans. In vitro cultures of seedlings, shoots, and callus have been produced to obtain plant materials useful for the production of these metabolites. The secondary metabolite profile was evaluated by HPLC-DAD. The extracts of all the in vitro material contained the flavonoid daidzein, while plicatin B, erybraedin C and bitucarpin A were found only in the extracts of the in vitro shoots and in wild shoots. The furanocoumarins angelicin and psoralen were found in in vivo and in vitro plants, but in the callus were not detectable. The extracts were also tested for cytotoxic activity in HeLa cell culture; the highest level of cytotoxicity was found in in vitro shoot extracts.

Myrtus communis L. is a Mediterranean species well known for ornamental and industrial utilization; the micropropagation protocol has been established and used by commerciai firms but the acclimatization phase must be investigated in greater depth. Furthermore owing to its peculiar characters, this species could be a model plant for woody shrub cultured in vitro. It is well known that the quality of plantlets cultured in vitro is the bottleneck affecting the acclimatization phase of micropropagated plants of many species; thus, the aim of this study was to examine the effect of several variables (Iight intensity, hormonal treatments) on chlorophyll content, on plant quality and acclimatization performance. Three Myrtle ornamental genotypes differing in height and other morphological characters, were cultured in vitro at 3 PPFD (25-50-100 micromol m-2 S-I) combined with hormonal rooting treatments including auxins (lAA and IBA) and the cytokinin BA. After 40 days, rooted and non rooted plants were transferred in the greenhouse for acclimatization. High light intensity decreased the chlorophyll (a+b) level in both rooted and non-rooted plantlets. The addition of a small amount of BA (0.1 mg L-I) in the rooting medium produce a higher rooting percentage and higher chlorophyll content compared to the other culture conditions. It is also interesting to note that in this species non-rooted plants cultured in vitro in the presence of BA and having a higher chlorophyll content survived better to the transfer in acclimatization.

Curcuma longa L. (turmeric) is one of the most important spice and safe food additives. Its main constituents, curcuminoids, showed anti-inflammatory, antitumor and antioxidant effects. In the present work, an in vitro propagation method was developed to achieve selected plant organs with quantified curcuminoid content. In vitro plants were obtained from sprouting buds as primary explants. The major curcuminoid constituents, such as curcumin (CUR), demethoxycurcumin (DEM), and bis-demethoxycurcumin (bis-DEM) were examined in different organs by LC-DAD-ESI-MS. A significant production of curcumin (more than 260 microg g(-1) fresh weight) was obtained from in vitro microrhizomes, especially grown in a Murashige and Skoog medium (MS) supplemented with kinetin (0.1 mg L((-1)), alpha-naphthaleneacetic acid (NAA, 1 mg L(-1)), sucrose (6%), agar (5%) and activated charcoal (0.1%). The analyzed microrhizomes showed reduced amounts of DEM and bis-DEM in comparison with CUR levels. In addition a shoot culture line was suitable to biosynthesize curcuminoids, in a ratio very similar to that identified in the fresh rhizomes of parent plants. This study represents the first direct quantification of curcuminoids in turmeric in vitro shoots and microrhizomes to be used in dietary supplements.

Dwarf fan palm (Chamaerops humilis L.) is an important Mediterranean species well known for many uses such as gardening, environmental restoration, and technological uses. Dwarf fan palm is usually propagated from seed, which takes up to 100 days to germinate. The germination pattern of dwarf palm seeds was studied during a 100-days length period in relation to different pre-sowing treatments (hot water, sulphuric acid, or mechanical scarification) in comparison to untreated control. A covariance analysis was performed to test the effect of time within seed-treatment treatment. All germination patterns were significantly fitted by a S-shaped (sigmoidal) distribution function with the general equation y=β+α/(1+exp(-(x-μ)/s)). Treatment with sulphuric acid significantly increased the final germination in comparison to untreated control. No differences were observed in % germination among the other seed treatments. Seed treatments increased by three- to seven-fold the maximum germination rate and reduced by 26% the mean germination time in comparison to untreated control. The reduction in mean germination time, and the increase in percentage germination and germination rate may have economical implication in the production of dwarf palm and its involvement in environmental restoration strategies, with no need to use dangerous or expensive acid pre-treatment in order to increase the propagation success.