WEEDINESS OF CROPS AND YIELDING CAPACITY OF FIVE-COURSE ROTATION CROPS DEPENDING ON MINIMIZING OF MECHANICAL TILLAGE

Abstract

This article is dedicated to studying the impact of various measures for minimizing of the mechanical tillage (changing of traditional ploughing into loosening the soil by a subsurface cultivator at the same depth or disking the soil to the depth of 10-12 cm) on weediness of crops and yielding capacity of crops of five-course rotation. Increasing of the weed amount in crops of spring barley, soybeans and corn at the beginning of the vegetation period was found in the result of the study. Their level did not exceed 50-60% in most cases. By the middle of vegetation period of examined crops, the number of weeds was significantly reduced in corn crops and the difference between the variants was even less indicated. This happened through increasing their phytocoenotic ability and loosening between rows in corn crops. The amount of weeds in crops decreased by 4-5 times in comparison with non-herbicidal background, and the difference between the examined variants was reduced to its minimum in case of herbicides using in crops of examined plants. By the end of the vegetation period the number of weeds was reduced more at herbicide background and was slightly increased at non-herbicidal research background. In the middle of the growing season of the examined crops, the difference of weeds by mass was less expressed than by quantitative indexes, indicating that ability of weeds to do harm was not so high in these variants despite the quantitative indexes.Yielding capacity of the examined crops while changing of ploughing into the soil loosening by a subsurface cultivator had insignificant tendency to decrease, which was not mathematically proved at both non-herbicidal and herbicidal background. This indicates the possibility of such changing under all examined crops. Instead, usage of disking as main tillage resulted in a significant reduction in the yield of spring barley, soybeans and corn during all the research years. In our opinion it is due to the essential increase in number of perennial weeds because of the inability of quality cutting of root system during tillage to a depth of 10-12 cm.