The work presents the results of the comparative study of the soil seed bank of weeds at crop cultivation in 2 three-fi eld crop rotations (wheat-wheat-oats and wheat-wheat-cabbage crops) using traditional and No-Till technologies. The research was carried out on leached chernozem of central forest-steppe of Priobskiy agricultural landscape area. Before the stationary experiment was laid in 2008, the soil layer of 0-10 cm contained an average of 31800 weed seeds on 1 m2 , and in the layer of 11-20 cm their number was 21200 pieces. Among the 17 identifi ed species, the redroot amaranth dominated. After the fi rst year of crop vegetation, the weed seed bank has grown by 2.2 times with the traditional technology, and by 1.3 times with No-Till technology. By the beginning of the second crop rotation in 2011 in the soil layer of 0- 10 cm there was about the same number of weed seeds with either technology: 41250±2532 pieces/m2 . At the same time, it was noted that the share of bluegrass weeds increased to 25.5-32% with No-Till technology and up to 34.8-35.5% with the traditional one. After the third crop rotation in 2016, the soil seed bank decreased by 5.7 times compared to 2011 with the traditional technology, and by 8.1 times with No-Till technology. The share of bluegrass weeds increased to 67.8% and 47.8%, respectively. The data obtained confi rm that mechanical tillage, which facilitates embedding weed seeds in the soil, ensures their more active germination, further development and distribution. The absence of mechanical tillage, which excludes contact of weed seeds with the soil, as well as the systematic use of herbicides reduce the weed seeds supply in the soil bank with No-Till technology.
INFLUENCE OF TECHNOLOGY OF SPRING WHEAT CULTIVATION ON THE SOIL SEED BANK OF WEEDS
