Essential oils (EOs) from the roots, stems and leaves of Plectranthus barbatus (A) and Plectranthus caninus (B), cultivated in north Italy, were obtained by steam distillation and chemically characterised by gas chromatography-mass spectrometry. The highest yields were obtained from roots (268.15 and 673.60 mg/kg from A and B), followed by leaves (64.34 and 26.65 mg/kg) and stems (19.76 and 18.63 mg/kg). A total of 128 structures were identified in A and 121 in B. Fe(++) chelating and antiradical activities (DPPH and ABTS) were evaluated: root and stem EOs showed the strongest activities, while EOs from leaves did not show relevant activities. All EOs were tested for their in vitro antimicrobial activity, showing optimal growth-inhibition in antibiogram (∅>35 mm) and MIC tests (32-64 μg/mL) against Candida albicans, while EOs from leaves of both species showed a good activity (25 < ∅ < 34 mm, MIC 64-128 μg/mL) against Escherichia coli.

The experiment was aimed to evaluate the effect of a biofertiliser containing the purple nonsulfur anoxygenic phototrophic bacterium Rhodobacter capsulatus (Ores, PSBIO System, Italy) on the growth of two poinsettia cultivars, 'Peterstar' and 'Maren', in comparison with the usual nitrogen fertigation. The plants were grown in a PMMA covered greenhouse, in 18 cm diameter pots filled with a peat based commercial substrate. Five treatments were compared: 1) the untreated control; 2) 120 mg N as NH 4 NO 3 per pot applied fortnightly from the pinching until the middle of November (in total 1320 mg N/pot); 3)-4)-5) biofertiliser Ores applied four times, the doses being 20 ml per pot of solution containing 0.75, 1.5 and 3 ml of the commercial product per litre of water, respectively. Before potting, the rootballs of the plants were immersed in the biofertiliser, then the biofertiliser was injected three more times at monthly intervals into different zones of the substrate. The experimental design was a split-plot, the cultivars being in plots and the treatments in sub-plots; there were three blocks and 8 replicates, with 240 plants total. Two weeks after potting, all the plants were pinched to eight nodes, and then fertilised every twenty days with a solution containing (mM) 1.5 P,

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The use of chemicals to control weeds in flooded rice in the Po Valley, Italy is restricted by limited knowledge of potentially useful herbicides. Different strategies of chemical weed control, including different application timings of several types of herbicides are compared based on effectiveness and selectivity. Echinochloa spp., the most common weed was, in the experimental conditions, better controlled with early applications (pre-sowing and preemergence) of new herbicides which were effective substitutes for molinate, the use of which is no longer allowed in some Italian areas. Alisma plantago-aquatica, Bolboschoenus maritimus and Schoenoplectus macronatus were controlled by different types of herbicides applied post-emergence. Cinosulfuron (sulfonylurea) showed the highest effectiveness and selectivity in controlling the more common Hetherantera spp., even when applied in very low amounts.