Molecular phylogenetic,morphological, and pathogenic analyses reveal a single clonal population of Septoria lycopersici with a narrower host range in Brazil

Septoria leaf spot, caused by Septoria lycopersici, is considered one of the most important diseases of tomato in Brazil. Despite its importance, the disease agent is still poorly studied. Septoria isolates collected from different production regions of Brazil were characterized by molecular, morphological, and pathogenic methods. A set of 104 isolates was sequenced for the DNA Tub, Cal, and EF1-α loci. Ten isolates were selected, according to geographical region of origin and type of leaf lesion (typical or atypical), for morphological characterization and for evaluation of aggressiveness on tomato cultivar Santa Clara. To evaluate the pathogen host range, cultivated and wild Solanaceae plants were inoculated with four selected isolates. The results showed that all isolates grouped with the type isolate of S. lycopersici in maximum likelihood and Bayesian inference trees. The isolates were morphologically similar. All isolates selected for pathogenicity testing on tomato were able to induce typical symptoms of the disease, but differed in their aggressiveness. A total of eight species of Solanaceae were also identified as potential alternative hosts for S. lycopersici. This information will provide a more accurate assessment of the risks involved with the introduction of new crops, especially of the genus Solanum, in areas where the species is already present. In addition, it will provide the basis for the establishment of more efficient methods in the management of Septoria leaf spot of tomatoes in natural conditions and in the different production systems.     

Efficacy of atenolol as a single antihypertensive agent in hyperthyroid cats

beta-Adrenergic blockers, particularly atenolol, are often recommended for the tachycardia and hypertension that accompany hyperthyroidism; however, the effects of monotherapy with atenolol on both systolic blood pressure (SBP) and heart rate (HR) have not been reported. Twenty hyperthyroid cats with SBP > or = 160 mmHg were studied retrospectively to investigate the SBP and HR lowering effects of atenolol. Median pre-treatment SBP and HR for all cats were 186.5 mmHg and 231 beats/min, respectively. All cats were treated with atenolol at a dosage of 1-2 mg/kg PO q 12h for a minimum of 5 days prior to reassessment and treatment with radioactive iodine. SBP and HR both decreased following atenolol therapy in this group of cats to median values of 171.5 mmHg (P=0.0088) and 185/min (P=0.0003). However, when successful clinical control of hypertension was defined as a post-treatment SBP < 160 mmHg, atenolol monotherapy was ineffective in 70% of the cases. There was no statistically significant difference in baseline serum total thyroxine or atenolol dosage between clinical responders and non-responders. While atenolol effectively reduces HR in most cats with hyperthyroidism, elevated SBP is poorly controlled, and the addition of another vasodilator such as amlodipine or an angiotensin converting enzyme inhibitor is needed to treat associated hypertension.     

Wild Seed Harvesting at Mountainous Species-Rich Grassland in Calcareous Italian Alps

Wild harvesting is an efficient option for supplying seed to be used for restoring seminatural grasslands. Several methods are currently used to implement wild harvesting, but few controlled experiments have investigated its efficiency regarding seed amount and number of species collected. A harvesting trial was conducted in a species-rich, low-productivity grassland of the calcareous Italian Alps (1 030 m above sea level [a.s.l.). Three mechanical methods were tested in three replications using a completely randomized block design: green hay (GH), dry hay (DH), and seed stripping (SS) harvesting. The number of fertile shoots, mature seeds, and species collected was recorded and compared with the standing seed yield (SSY). GH, DH, and SS harvested approximately 84%, 70%, and 29% of SSY, respectively. Forbs were harvested more efficiently than grasses in all methods but in most cases at very low seed amounts per m² due to their low seed density for SSY. No significant difference among methods was found for the number of species collected as mature seeds, but SS, implemented on larger plots, tended to collect more forb species. Comparing the results with those of other experiments demonstrated that the relatively cool temperature of the seed maturation period at the mountain site favored stronger seed retention and therefore increased the GH and DH efficiency but decreased the SS efficiency. In cool mountain areas, wild harvesting from forb-rich grasslands should be more successful by SS implemented on wide areas and several times over the vegetative season. In less species-rich grassland, GH and DH can efficiently collect high seed amounts of the fewer species present, even if implemented over smaller areas.