Proceedings Volume 2010 (format .pdf) - SimpBTH

1991). This imposes the need of new studies to increase the scope of possibilitiesfor weed control and to maintain weed populations below economic harm.The main problem with weeds is their great diversity of species and highecological and biological plasticity, which facilitates the rapid dissemination andadaptation.The aim of the study is to determine the influence of soil processing andfertilization on the development of weeds in crops of alfalfa grown for forage.MATERIAL AND METHODS:The experiment was set at the method of the long plots of II experimentalfield in EFC – Pleven, with slightly leached black earth soil (Haplic Chernozems,loamy) at the area of 6 acres, with a size of the experimental plot of 30 m2 in fouriterations with the following agrochemical characteristics:SampleNr.Table 1. Agrochemical characteristics of slightly leached black earth soilрН рН N/ P 2 O 5 / K 2 O/ C х Humus(в Н 2 О) (в KCl) 1000 g 100 g 100 g%1 6,95 6,04 31,50 5,19 - 1,03 1,772 6,68 5,67 33,95 3,94 - 1,37 2,363 6,54 5,55 32,55 3,18 - 1,34 2,314 6,31 5,30 35,70 3,16 - 1,28 2,215 6,24 5,20 32,55 3,22 - 1,57 2,71The experiment is made as two-factor and includes:Factor F – fertilization with the following rates of factoriality:F 1 . Control – Non FertilizedF 2 . N 6 P 10 K 8 – on the approved technologyF 3 . N 2,3 P 10 K 3,5 – the nitrogen ½ in I year, ½ in III year, the phosphorusand the potassium as a stock.F 4 . N 2,3 P 10 K 3,5 - the nitrogen before sowing, the potassium as a stock,the phosphorus 1/3 in 1,2 and 3 yearsF 5 . N 3,5 P 8 K 5,0 – the nitrogen before sowing, the phosphorus and thepotassium before the processingF 6 . Amofos – 25,0 kg/da – calculated at the rate of fertilization N 2,7 P 12K 0 .and the factor Т – soil processing:T 1 loosening at the depth12 – 15 cmT 2 ploughing at the depth12 – 15 cmT 3 ploughing at the depth22 – 24 cm - control193