Krzysztof Kalinowski

Background. Titanium applied via roots or leaves stimulates plant growth. Titanium exerts a favourable effect on plant growth only at low concentration, while at higher concentrations it may exhibit toxic effects. Determining the optimal doses and dates of titanium application are very important in the optimisation of early potato production.Material and methods. The effect of dose (0.2 dm3·ha-1 or 0.4 dm3·ha-1) and date (leaf development stage – BBCH 14-16, tuber formation stage – BBCH 41-43, and at both leaf development stage and tuber formation stage) of a Tytanit® application (8.5 g Ti in 1 dm3) on the assimilation leaf area and chlorophyll content of very early-maturing potato cultivars was investigated. The field experiment was established as a split-block-split-plot design with a control object without Tytanit®. The assimilation leaf area was measured by the weight method and the chlorophyll content was estimated using a chlorophyll meter SPAD-502.Results. Tytanit® caused an ...

The study examined the effects of the sowing date (5, 15 and 25 May) and plant spacing (1 × 0.6 m, 1 × 0.8 m and 1 × 1 m) on the content of carotenoids and L-ascorbic acid in the fruits of two cultivars of spaghetti squash (‘Makaronowa Warszawska' and ‘Pyza’). The field experiment was carried out in central-eastern Poland. Fully mature spaghetti squash fruits were harvested from the beginning of September to the beginning of October. The content of total carotenoids and β-carotene was the greatest in the fruits of plants sown on 15 May. The sowing date did not affect the content of L-ascorbic acid. Increasing the plant spacing from 1 × 0.6 m to 1 × 1 m resulted in an increase of total carotenoid content, particularly for the spaghetti squash sown on 25 May. Plant spacing did not have a significant effect on the content of β-carotene and L-ascorbic acid. Fruits of the ‘Makaronowa Warszawska’ with light orange flesh contained more total carotenoids and β-carotene than fruits of th...

A finite-buffer queueing system of the M/M/1/N type is used for modeling the operation of a single-machine production line with cyclic failure-free and repair periods. The arriving jobs enter randomly according to a Poisson process and are being processed individually with service times having the common exponential distribution. After an exponentially distributed working period a breakdown of the machine occurs, starting an exponentially distributed repair time during which the service process is stopped. At the completion epoch of the repair time a new working period begins and so on. A system of integral equations for conditional probability distributions of the number of jobs completely processed before the fixed time t (departure process) is built, using the concept of embedded Markov chain and the total probability law. Applying linear-algebraic approach the compact-form solution of the corresponding system written for double transforms of departure process is found.