EJPAU, 2003, Volume 6, Issue 1
Agronomy

In order to compare the effect of organic and mineral fertilization of various soil types, long-term fertilization experiments frequently use indices, being a function of various parameters considered simultaneously; the content of organic carbon, microbiological parameters and soil enzymatic activity. The aim of the present research was to define soil fertility based on the values of Biochemical Soil Fertility Index (B). The index has been formulated based on the research results obtained: enzymatic activity, content of organic carbon and total nitrogen. The research material was sampled from topsoil of a many-year experiment which included varied organic and mineral fertilization, established on typical lessive soil. Soil samples were collected in 1998 from winter wheat stand, four times over the vegetation period. The following enzymes were determined: dehydrogenases, alkaline phosphatases, proteases and amylases. Additionally C_org and N_total and pH in 1 M KC

The present paper covers economic analysis (concerning energy and cost aspects) of rye production technologies employing different cultivars, sowing dates, NPK fertilisation, microelements nourishment and weed control. Intensive production of rye using a hybrid cultivar, early sowing and NPK fertilisation at 176 kg·ha^-1 produced 46% higher yields compared to extensive technologies involving open pollination cultivars and low fertiliser rates. The highest energy consumption in winter rye production was caused by NPK fertilisation. Intensive technologies were less energy-effective than extensive methods. The direct costs of growing 1 ha of rye in extensive technologies equalled 2.2 – 2.9 t grain. In intensive technologies direct costs were returned at yields as high as 3.9 – 4.6 t per ha. The yield value increment resulting from more intensive production methods did not cover completely the increase in direct costs. Therefore, the surplus of production in intensive technolog

The article presents the response of an open pollinated cultivar ‘Warko’ and a hybrid cultivar ‘Esprit’ of winter rye grown on good rye soil suitability complex to delayed sowing date, NPK fertilisation levels, fertilisation with microelements and weed control. The experiment was established in a half replication k^n-1 type design. The hybrid cultivar ‘Esprit’ produced yields that were on average 18% higher than those obtained from the open pollinated cultivar ‘Warko’. Delaying the date of sowing by two weeks decreased the winter rye yields by about 10%. The response of both cultivars of rye to the sowing date was identical. The effectiveness of yield increase under the influence of the maximum fertilisation rate was higher for the open pollination cultivar ‘Warko’. Chemical weed control of rye saved 0.24 t grain per ha. The yield of winter rye was determined by the number of ears per 1 m² and 1000 seed weight. However, the contribution of these two grain yield componen

The pot experiment investigated the effect of varied soil moisture (60-70% and 30-35% of capillary water capacity) from flowering through pod setting, on the intensity of photosynthesis, transpiration, intercellular CO₂ and stomatal conductance, some biometrics, seed weight per plant of different pea forms ('Jaspis', traditional cultivar and ‘RRRbRb’, homozygotic izoline) and yellow lupin ('Teo', traditional cultivar, and ‘Markiz’, self-completing cultivar). The research results showed that in the objects with a lowered moisture of 30-35% capillary water capacity of soil, the intensity of photosynthesis decreases, as well as that of transpiration, intercellular concentration of CO₂ and stomatal conductance in pea and yellow lupin. In the conditions of water deficit, the seed weight per plant in yellow lupin cultivars tested decreased significantly, while the seed weight per plant in the pea forms researched did not vary significantly.

Field and laboratory experiments aimed at the assessment of the impact of diluted methyl alcohol applied overhead 4-5 times in one-week intervals on growth and yield of tomato, bean, sugar beet, oil seed rape, as compared to supplemental irrigation. The photosynthetic activity was measured in situ with an LC-4 gas analyser. The crops when treated with methanol solutions yielded 20-30% higher than the control. The yield increases were comparable to those caused by supplemental irrigation. The increased biomass synthesis caused either by irrigation or methanol application was due to enhanced carbon dioxide assimilation, transpiration, leaf conductivity, and higher activity of nitrate reductase and alkaline phosphatase.

Over 1998-2000 field experiments were carried out to define the effect of various organic fertilisers and the tillage methods on the content of nitrogen in soil and yielding and the quality of ‘Ibis’ potato tubers. The research showed that fertilising the potato with manure or white mustard stubble intercrop enhanced the tuber yield and decreased their accumulation of nitrate nitrogen. Manure as compared with other fertilisers tested ensures also the best health status of tubers after harvest and after storage. However barley straw facilitates nitrate nitrogen liberation and its increase in tubers and deteriorates their storage life, causing an increase in rots. On the other hand, ploughless tillage (with cultivator) decreases the yield and causes tuber infection with common scab, increasing the nitrates in topsoil and in potato tubers and total losses after storage.