Light, temperature and burial depth effects on Rumex obtusifolius seed germination and emergence

Trials were carried out to investigate the effects of light and temperature on germination of Rumex obtusifolius L. After several months of storage, seeds gradually lost dormancy and became photosensitive. Thermal optima for germination were between 20 °C and 25 °C in light or in darkness. At lower temperatures there was a greater demand for light, so that the greatest differences in germination percentage (between low and high temperatures) were found within the 10–15 °C temperature range. The calculated thermal minima ( x -intercept method) in light and darkness were 8.3 °C and 6.1 °C respectively. Daily temperature fluctuation increased germination even after seed irradiation with far-red light, suggesting a lower demand for the far-red-absorbing form of phytochrome. Seed burial inhibited germination in proportion to depth; however, germination inhibition was independent of seed phytochrome photo-equilibrium, which had been diversified by seed pretreatment with light. Seedlings did not emerge when seeds were buried >8 cm deep. Recovery of ungerminated seeds showed that excessive burial did not impede seedling emergence but rather prevented seed germination. However, this induction of dormancy was lost once germination processes were activated (24–48 h at 20 °C) that made germination irreversible. Temperature was also involved in inhibition, and low temperature (<15 °C) induced the least inhibition. This is discussed in terms of processes of respiration and fermentation in buried seeds.     

Bilateral microphthalmia and aphakia associated with multiple eye abnormalities in a free-living European red deer calf (Cervus elaphus)

A free-living European red deer calf (Cervus elaphus) was euthanized due to bilateral microphthalmia. Lens was missing, replaced by proliferating squamous epithelial cells; hyperplastic squamous cells, sebaceous and mucinous glands were observed within the cornea with the characteristics of inclusion cyst. Findings were consistent with congenital microphthalmia/aphakia, with multiple eye abnormalities.     

Bioactive compounds from Capparis spinosa subsp. rupestris

Aim of this study was to determine the content of bioactive phytochemicals in Capparis spinosa subsp. rupestris (syn. C. orientalis), a less investigated species of caper and compare the chemical profile of this species with that of other studied Capparis sp. and especially with the related cultigen C. spinosa subsp. spinosa. Chemical composition of seed oil and glucosinolates, as well as of glucosinolates and flavonoids from the aerial parts of the plant have been determined and data reported here. Oil from the plant seeds is rich in unsaturated and rare lipids such as cis-vaccenic acid; the main glucosinolate is glucocapperin. The aerial parts are characterized by rutin as the dominant flavonoid. The overall phytochemical data obtained from the analysis of C. spinosa subsp. rupestris indicate that this species represents a very rich source of bioactive compounds of nutraceutical relevance although the compositional profile does not differentiate this subspecies from C. spinosa subsp. spinosa.     

A distinct CDV genotype causing a major epidemic in Alpine wildlife

Canine distemper virus (CDV) infection represents an important conservation threat to many carnivore species and has contributed to the population decline of several wild terrestrial and aquatic mammalian species. Since 2006, the Alpine region of North-Eastern (NE) Italy has been experiencing a severe and widespread outbreak of CDV affecting the wild carnivore population. In this study we performed an extensive phylogenetic and molecular evolutionary analysis of CDV identified during the recent wildlife epidemic in the Alpine region. Our analysis yielded data on the evolutionary dynamics of the Alpine wildlife CDV epidemic and revealed the emergence and spread of a single genetic cluster of CDV. The wide distribution of the novel cluster combined with the identification of a specific amino acid mutation, which is believed to increase the ability of the virus to replicate in a wider host range, raises concerns over the possible implications of the spread of this virus on the conservation of endangered wildlife species.     

Essential oils from Mediterranean lamiaceae as weed germination inhibitors

The essential oils obtained from rosemary (Rosmarinus officinalis L.), thyme (Thymus vulgaris L.), and savory (Satureja montana L.) and the four monoterpenes that are their major constituents have been analyzed by GC and GC-MS and tested for their allelopathic properties on the seeds of three different annual weeds (Chenopodium album, Portulaca oleracea, and Echinochloa crus-galli) and three crops (Raphanus sativus, Capsicum annuum, and Lactuca sativa), with the aim to evaluate in vitro their potential as germination inhibitors. The essential oil composition varied with the species, thymol being the main constituent (44%) of thyme and carvacrol (57%) that of savory oil. Differences in essential oil composition were observed within two different rosemary ecotypes, type A, with alpha-pinene (37%) and 1,8-cineole (23%), and type B, characterized by a 2-fold content of 1,8-cineole (47%). This latest essential oil inhibited completely the germination of weeds while concurrently displaying little effect on pepper. The other two oils showed less selective action. S. montana essential oil, with 57% carvacrol, is the most active compound, completely inhibiting germination both of crops and weeds. Borneol, one of the main constituents of the oil of rosemary type B, showed an activity comparable to that of the whole oil. Crop and weed seeds treated with 1,8-cineole showed germination values that were not significantly different from controls, even if a slowing of the germination process expressed in terms of a significant increase in mean germination time was observed. Monoterpene compounds also present in the essential oils mainly represented the volatile fraction released from the crops and their residues into the soil.     

Main agronomic-productive characteristics of two ecotypes of Rosmarinus officinalis L. and chemical composition of their essential oils

The productive potential of two different ecotypes of Rosmarinus officinalis (Cevoli and Lunigiana) cultivated in the littoral area near Pisa (northern Tuscany, Italy) and the differences in the yield and composition of the essential oils of leaves, flowers, and stems obtained from different positions of the plants were used to characterize the two ecotypes. The Cevoli ecotype plant produced the highest yield of dry matter (221 g plant-1) in comparison to the Lunigiana ecotype (72 g plant-1). There were significant differences in dry matter production of different organs of both ecotypes. The essential oil contents of Cevoli and Lunigiana ecotypes were similar. In contrast, the oil contents of the different plant parts showed marked differences. The apical part of the plant and the leaves gave the highest essential oil yields. The major difference between the oils of the two ecotypes consisted in the 1,8-cineole contents (6.6 and 37.9% in Cevoli and Lunigiana, respectively). The Cevoli ecotype was determined to be the most suitable for essential oil extraction because it was characterized by a preponderance of flowers and leaves in the apical portion. The Cevoli ecotype could be classifited as an alpha-pinene chemotype, whereas Lunigiana is a 1,8-cineole chemotype.