Evalution of the healthiness of winter wheat cultivated in conventional tillage, direct sowing and direct sowing with underplant crop of white clover

摘要

Research of the healthiness of winter wheat depending on the soil tillage system and rate of nitrogen fertilization were carried out in 1998-2001. The largest threat to the healthiness of plants was tan spot, which was caused by Pyrenophora tritici - repentis , especially in cropping season 1999/2000. The soil tillage system diversified the intensification of occurence of this pathogen, only in two last years of research. The most infected by P. tritici -i was wheat, which was cultivated in the direct sowing. Application of underplant crop of white clover in the direct sowing contributed to the improvement of the plants healthiness. The highest rate of nitrogen fertilization (120 kg N.ha -1 ) in the highest degree favoured the damage of wheat by P. tritici - repentis , but only in two first years of research. The second pathogen Blumeria graminis , which caused powdery mildew of cereals, occured in small amount and didn't have any influence on the healthiness of winter wheat.