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The effect of different cytokinins on multiple shoot regeneration from shoots of Centaurea ultreiae was studied. The culture system consisted of solid basal halfstrength Murashige and Skoog medium supplemented with one of four cytokinins [6-benzyladenine (BA), zeatin, kinetin, or N 6 -(2-isopentyl) adenine (2-iP)] at each of five different concentrations. The highest multiplication rate (5.52 shoots per explant) was obtained in the medium supplemented with 4.44 lM BA. Shoots were successfully rooted (91% success) by dipping the basal end into a solution containing 10 M 1-naphthaleneacetic acid for 30 s. Genetic stability of the regenerated plants was assessed by random amplified polymorphic DNA (RAPD) analysis and flow cytometry. In the initial randomly selected plant material (control) and 20 of its regenerants, 2,688 bands were generated by RAPD with 12 different primers, and the same banding profiles were exhibited. Molecular and cytological analyses did not reveal genomic alterations in any of the regenerated plants obtained on medium containing 4.44 lM BA. The success of acclimatization to environmental conditions-100% of plants were successfully acclimatized-suggests that the micropropagation system described is a reliable method for propagation of C. ultreiae.

Alternaria solani Soraeur produces early blight in Solanum tuberosum L., leading to significant agricultural losses. The current study was carried out on the extensive potato crop situated in north-western of Spain during 2007, 2008 and 2009. In this area potato crops are the most important source of income. In this work we used a Hirst-type volumetric spore-trap for the aerobiological monitoring of Alternaria spores. The highest spore concentrations were recorded during the 2009 cycle (10,555 spores), and the lowest concentrations were recorded during the 2008 cycle (5,471 spores). Over the 3 years of study, the highest concentrations were registered during the last stage of the crop. The aim of the study was to observe the influence of meteorological factors on the concentration of Alternaria spores, which can lead to serious infection and early blight. Prediction of the stages during which a crop is particularly vulnerable to infection allows for adjustment of the application of fungicide and is of environmental and agricultural importance. For this reason, we tested three models (P-Days, DD and IWP) to predict the first treatment and decrease the negative effect that these spores have on potato crops. The parameter that showed the most significant correlation with spore concentrations was minimum temperature. We used ARIMA (autoregressive integrated model of running mean) time-series models to determine the forecast. We considered weather data as predictor variables and the concentration of spores on the previous day as the fixed variable.

A study of Rubus honey was conducted to determine their sugar composition, physicochemical properties, phenol and flavonoid contents, and sensorial and pollen characteristics. The principal pollen types present in the studied samples were Rubus, Castanea and Cytisus. Other pollen types such as Trifolium, some Erica sp., Eucalyptus or Echium were present in more than 50% of the pollen spectra. The sensorial characteristics of Rubus honey were amber-to-amber dark in colour, floral and ⁄ or vegetal olfactory perceptions with mediumto-low intensity and persistence, medium floral aftertaste and a fruity aroma. Physicochemical analysis showed that the honey had good quality and freshness. Phenol and flavonoid contents varied greatly and were related to the mineral content and colour of the honey. A stepwise regression analysis was performed using colour as the dependent variable, and flavonoid, electrical conductivity, and Rubus pollen as the independent variables.