engleski

Effect of twenty years of tobacco production in monoculture and crop rotation upon the yield and NO3-N leaching on semigley soil in Croatia

Investigations started in 1987 and were carried out on semigley soil (sandy loam) characteristics of the area where flue-cured tobacco is grown in Northern Croatia. Several types of crop rotation were tested: tobacco monoculture (unfertilized tobacco, fertilized tobacco), two-crop (winter wheat, tobacco), three-crop (winter wheat, tobacco, maize), four-crop (winter wheat, tobacco, maize, soybean). Tobacco is the key crop in these investigations while winter wheat was the proceding crops in trials. This investigations will have a long-term character and are carried out on the experimental field of the Tobacco institute Zagreb. Tobacco growing in monoculture reduced the yield from 2.63 t/ha in the first year (1987) to 1.63 t/ha in the 20. year (2007). A significantly lower yield and quality were obtained after the fourth year of tobacco monoculture compared to tobacco growing in crop rotation. The highest content in plough and sub-plough layers was recorded at lysimeter where the crop rotation involved maize and wheat, which was succeded by tobacco. The lowest nitrate content (7.8 kg NO3- N/ha) was leached in unifertilized tobacco monoculture which served as check treatment. The highest content of leached nitrogen (53.6 kg/ha NO3- N) was recorded after the harvest of maize, which was fertilized with 180 kg nitrogen, wheat fertilized with 160 kg of nitrogen, was shown.

Semigley soil; Monoculture; Crop rotation; Tobacco; NO3- N; leaching

nije evidentirano