Ida Kincses

Dissolved organic carbon (doc) and dissolved organic nitrogen (don) content of an arenosol as affected by liming in a pot experiment

The effect of liming materials was investigated on the dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) content of the soil in a pot experiment on an acidic soil using oat (Avena sativa L. ) as an indicator plant. Soil samples were taken three times during the growing season. The lime rates applied were 0, 1, 2, 3 g calcite/pot and 0.92, 1.84, 2.76 g dolomite/pot, respectively. Due to an increase in soil pH and microbial activity the DOC concentration significantly increased with increasing lime doses at all three samplings. An exponential relationship was found between soil pH and DOC concentration: y v = v 0.3733e 0.7893x , r v = v 0.903***. Lime had a significant effect on DON concentration at the first sampling, while for the remainder of the growing period no further significant increases were found. This could be explained by the fact that the biodegradability of DOC and DON differs under conditions of the experiment, resulting in a decrease in the N content of the dissolved organic matter, while the amount of DOM and DOC increased with increasing pH. Because of the above mentioned facts the DOC/DON ratio increased significantly with liming. There were no significant changes in the dissolved organic carbon content of the soil during the 15-week growing period, while DON concentration decreased significantly. It can be explained by the initial addition of N fertilizer, which increased the DON quantity at the first sampling in the soil.

Effect of Application of Nitrogen and Different Nitrogen–Sulfur Ratios on the Quality and Quantity of Mustard Seed

A greenhouse experiment was conducted on a calcareous chernozem soil to investigate the effects of nitrogen (N) and sulfur (S) fertilization and their ratios on the yield and quality of white mustard (Sinapis alba L.). Four levels of N [0.5, 1, 1.5, and 2 g pot−1 N as ammonium nitrate (NH4NO3) and ammonium phosphate (NH4H2PO4)] in combination with three levels of applied N–S ratios [8, 4, 2; S as potassium sulfate (K2SO4) and sodium sulphate (Na2SO4)] were tested as treatments. Results indicated that a significant response to seed yield was observed for N and S application. Maximum yield, 24.8 g pot−1, was found when full doses of N and S were applied. Increasing N supply from 0.5 g pot−1 to 1 g pot−1 had little increasing effect in the oil content of the seed. Higher application of N doses (>1 g pot−1) decreased these values significantly. The maximum oil content (28%) was achieved with the 1 g N pot−1 treatment; the lowest values were observed in the pots applied with the highest N doses. Changes in the N content of the seed and straw showed a statistically significant increase with increasing N and S fertilization. Highest values in the seed and straw (5.96% and 0.87%, respectively) were observed by applying highest N and S doses. Seed and straw S levels were also observed to increase with increasing N rates and decreasing N–S ratio. Nitrogen doses significantly improved the quantities of essential amino acids with the exception of threonine, tyrosine, phenylalanine, and methionine. The amounts of these amino acids decreased with increasing N supply. When the N–S ratio decreased by increasing S, the quantities of valine, isoleucine, leucine, lysine, methionine, and cysteine increased significantly and the amount of tyrosine decreased. The quantities of nonessential amino acids with the exception of proline, histidine, and glycine increased with increasing N doses. In contrast, N rates decreased the amount of glycine. Decreasing the N–S ratio lowered the proline and arginine contents. The total amounts of essential amino acids slightly increased with increasing N rates and decreasing N–S ratio.

The effect of N and N/S supply levels on oil and protein content in mustard seed ( Sinapis alba L. )

Introduction Yellow mustard (Sinapis alba L.) is a annual spring crop and has been grown mainly in Europe since last century. Yellow mustard seed is suitable for a wide range of applications. It is grown for its seed, as a salad plant, as a green fodder crop or as green manure. Mustard seed is a nutritious food ingredient. Climate of Hungary is favourable for the cultivation of mustard. In spite of that little information exists on its fertilization, on the mechanism of its nutrient-uptake and its fertilizer activity in the international (Ahmad et al. 1998, Asare et al. 1995) and hungarian (EOry et al. 1996, K&d&r 2002) scientific literature. In the present study, an attempt was made to increase the amount of information for the effects of N supply and N/S ratio on the sulphur, nitrogen (crude protein), oil content and yield of seed.

EFFECTS OF NITROGEN AND DIFFERENT N:S RATIO ON YIELD AND NUTRIENT UPTAKE OF MUSTARD ( SINAPIS ALBA L.)

Introduction White mustard is cultivated for seeds, for green manure as animal feed, for green fodder crop (Minkevics and Borkovszkij 1951) and for compost. Mustard seeds are mostly used for the preparation of spices, oil, french mustard, mustard pastes which is a common condiment in food industries (Szabo and Fodor 2005). Climate of Hungary is favourable for the cultivation of mustard. In spite of this little information exists on its fertilization, on its nutrient-uptake in the foreign (Asare Scarisbrick 1995, Singh 2004) and Hungarian (Kadar 2002, Fodor Kadlicsko 2006) scientific literature. Mineral nutrition, especially sulphur and nitrogen are major factors affecting growth, yield and quality of mustard (Singh 2004). Nitrogen and sulphur are necessary for the synthesis of amino acids, proteins and various other cellular components, including thiol compounds and the so-called secondary sulphur compounds, which have a significant bearing on protection of plants against stress and pests. In the present study, an attempt was made to investigate the effects of N and N:S ratios on the yield and nutrient uptake of mustard (Sinapis alba L.).