WINTER BARLEY VARIETY FERTILIZATION AND NITROGEN-FERTILIZATION TRIALS ON SAND

On slightly calcareous sandy soil with moderate Al-PK, 0,8-1,0% humus content between the rivers Danube and Tisza over 4 years (1985-88) the response and yield of some registered winter barley varieties (Kompolti korai, Kompolti 4, GK. Omega, Rachel and Igri) were tested as effected besides uniform PK basic and 60 kg/ha N basic fertilization by 0,60, 90 and 120 kg/ha N-top fertilization. The aim of the trial was to determine the N-reaction and the optimal N-dose of the varieties, and to verify the most promising varieties for sandy soil. The results can be summed up as follows: 1. The N-top fertilization - despite the N-basic fertilization - increased significantly (by 1,76 t/ha) the grain yield, effected highly by the weather, in a smaller degree by the variety itself (Table 1.). 2. The optimal N-dose changed extremely from year to year due to direct and indirect effects of weather. On the 4-year average for the variety Kompolti 4 the 60+60 = 120 kg/ha N seemed to be sufficient, while for varieties GK Omega, Igri, Kompolti korai and Rachel the corresponding quantity: 60/90 = 150 kg/ha (Table 2.). 3. Also the yearly achieved yields varied significantly as they were influenced besides weather conditions to a large extent by the applied agrotechnics. By proper PK supply and efficient fungi control much higher yields (about 7 t/ha) could be achieved. 4. First of all the N-top fertilization raised the yield through increase in productive tillering but in the droughty year of 1986 it improved considerably also the ear-productivity. Also in that respect there are differences between the varieties. 5. On sandy soil of medium quality the highest yield was shown by the varieties with row number 2 GK Omega and Igri, so for such soils, these can be recommended to be grown. In trials on sandy soil of poorer quality it occurred, however, that the variety Kompolti korai achieved the highest yield. In that case the slightly better winterhardiness and more moderate soil demand of Kompolt varieties mean advantages. Based on trial results and experiences gained in connection with them it can be stated that also on medium or good quality sand adequate barley yields can be achieved if the right nutrient supply, plant protection and agrotechnics are applied, and the appropriate varieties are grown considering the characteristics of sandy soils. It should be noted however that the yields of winter barley are varying to a much greater extent on sand, depending on weather and applied agrotechnics, than that of wheat, therefore the production of winter barley needs even more attention and accuracy than that of wheat.