Influence of fertilizers, methods of soil treatment and plant management on infestation of oil crops in the course of crop rotation

A long-term experimental material derived in the course of stationary researches (1973-1992) is given, and analysis on the in-fluence of fertilizers, methods of soil treatment and plant management on infestation of oil crops in the course of crop rotation is conducted. By the use of herbicides and fertilizers infestation of crops was 15-25 pcs/m2 by their weight of 124-272 g/m2 re-gardless of the main soil treatment methods. By the absence of herbicides usage infestation by weeds was increasing in 2.4 times without fall soil treat-ment, and in 2.2 times by the minimum soil treatment. Number of perennial weeds increased from 1.3 to 2.8 pcs/m2, what stimulated yield reducing by the moldboard plowing by 9-39 %, by the minimum soil treatment or absence of it - by 23 and 51 % respectively. Yield level in the conditions of using the energy-efficient variants and moldboard plowing by using fertilizers, herbicides and crop management methods of crop rotation regulation was: 2.20 t/ha for sunflower; 1.20 t/ha for castor; 1.15 t/ha for coriander.