Four tomato (Lycopersicon esculentum Mill.) varieties commonly grown by tomato farmers in Tanzania were evaluated for resistance to bacterial speck (Pseudomonas syringae pv. tomato) and bacterial spot (Xanthomonas vesicatoria) diseases, along with five introductions under screenhouse and field conditions. The four tomato varieties were Cal J, Moneymaker, Tanya and Roma VF. Seeds of the tomato varieties were purchased from seed vendors in the open market. The introductions that were included in the study were Bravo, Taxman, Stampede (from Sakata-Mayford Seeds (Pty) Ltd, South Africa), Torquay and BSS436 (from Bejo Zaden B.V., The Netherlands). In the screenhouse, results indicated that all the tomato varieties were susceptible to the two diseases, and suffered moderate to severe infection levels. The performance of the introductions against bacterial speck under screenhouse conditions was variable. All the introductions showed high levels of susceptibility to bacterial spot. Under field conditions, incidence of the diseases was high in all the locally available varieties tested, averaging 87% for bacterial spot and 82.3% for bacterial speck. The results of this study indicate that all the locally available tomato varieties included in the study were highly susceptible to bacterial speck and bacterial spot diseases.

The paper describes the research on soft X-ray lasers with an active medium created using a gas puff target irradiated

with high-intensity laser pulses. The gas puff target in a form of an elongated gas sheet is produced by pulsed injection of

gas through a slit nozzle using a high-pressure electromagnetic valve. The method of generation of soft X-ray lasers using a

laser-irradiated gas puff target has been developed at the Institute of Optoelectronics. The collaborative experiments were

performed at various laser laboratories using high-intensity laser systems to irradiate the gas puff target and pump the X-ray

laser active medium. Results of these experiments are presented and discussed. Works aimed at increasing the efficiency of

X-ray lasers using a longitudinally irradiated gas puff target are also reviewed.

The paper presents the result of investigations of aluminosilicate (low silica - 25 mol%) and phosphate optical fibres. The methods of glass preparation and their properties are showed. A set of physical measurements including: DTA, DSC, DL analysis, absorption spectroscopy, visible and infrared absorption edges and thermo-physical properties were determined. The stable glass compositions were doped with rare earth elements. Selected properties of obtained glasses are: high transmission, refractive index 1.53-1.68, high solubility of RE ions (up to 10 wt%). Double-crucible and rod-in-tube drawing techniques were applied to obtain aluminosilicate and phosphate double clad optical fibres doped with neodymium and ytterbium ions. Luminescence spectra of manufactured glasses and fibres are presented.

ARGUMENTUM

Id, quod Agathias dicit de septem neo-Platonicis philosophis in aula Chosrois I hospitio acceptis, monstrat permagnam morum imperii Byzantini et Persici discrepantiam ignorantiamque mutuam.

The article corresponds to the 400th death annniversary of two famous European writers – Cervantes and Shakespeare – celebrated all around the world. The author tells about their lifes and takes into consideration the possiblility of their meeting together in Vailladolid. Besides, the author emphasizes on the qualities that are in common for Shakespeare’s and Cervantes’ works – among others the universality (their readers were both educated as well as simple), the ability to create symbolic figures and the application of colloquial language.