Ottó Pálmai

Analysis of weed abundance in winter wheat sown at different times

The following conclusions may be drawn from the experimental data: 1. in wheat area sown with high number of germinating seeds, weed abundance shall be low at spring, i.e. the number of weed species characteristic of cereals shall be little; 2. this trend is increasing with the advance in sowing time, the number of species keeps decreasing; 3. at the beginning of May, the germinating weeds of species T4 appear, and the frequency of these weeds indicates the weed abundance at harvest time and the composition of stubble vegetation; 4. weeds of species G1 and G3 are abundantly shooting (primarily from rhizomes) in the stubble vegetation,; 5. in cereal areas, the weed survey made at late spring and in stubble in one calendar year shall give information about the full composition of weed species characteristic of the area; 6. by identification with GIS, the change of weed species can be followed within the field.

Nitrogen and phosphorus balances of hungarian farms as management tools for sustainable agriculture

Abstract At the moment, Hungarian agriculture is confronted with a certain duality as far as nutrients are concerned. On the one hand, national soil nutrient balances show substantial deficits, and on the other hand, agricultural nutrient use is responsible for a part of the nitrogen (N) and phosphorus (P) losses to the environment. To understand this duality and help optimize farm nutrient management, the farm gate N and P balances of 12 farms, representing a variety of Hungarian agriculture, were calculated for the year 2002. The farm gate N and P surpluses/deficits in the east of the country were lower than in the west. This was correlated with a lower fertilization rate. The low soil fertility level due to a prolonged period of low fertilization in combination with continuing nutrient deficits can lead to possible future reduction in crop yields.

Evaluation of the N-fertilization of winter wheat based on the N MIN -method in farm practice

Introduction Among the major nutrients (NPK) nitrogen is most often the limiting element of crop production. On the other hand, in the case of overdosage, nitrogen can be harmful to the environment (especially for the quality of surfaceand groundwater). Most arable crops depend on nitrate-N as a main nitrogen source. In the mid-1970s the principles of an uniform fertilizer recommendation system were worked out with the necessary institutional and laboratory background. This procedure included soil sampling on the farm fields every third year, respectively (all fields which were bigger than 6 hectares were involved in the program), and giving fertilizer advice for each field (Baranyai et al., 1987). The system worked up to the end of the 1980s when political and economical changes occurred in the country. From the agricultural point of view several changes had happened: reprivatization of land, elimination of the former state subsidies, lack of capital and loan, etc. For the determination of the