No abstract

The purpose of the research was to establish the reason for the decrease in the productivity of crops grown in the experiments under replacing the main processing of moldboard plowing with flat-cut loosening to appropriate depths based on a review of the literature and our own experiments conducted on podzolized chernozem in a fve-feld crop rotation of soybeans – spring rape – spring wheat – oil flax – spring barley. According to the research data, the average yield of 15 crops decreased by 9.0 % due to such replacement. In our experience, the average yield of spring crops decreased by the same amount. Such a decrease in the yield of crops cultivated in different experiments against the background of flat-cut cultivation instead of plowing could not be caused by a deterioration in the physical condition of the soil due to the absence of the latter, sinse in 15 experiments, according to the literature data, the density of the addition of the arable layer of different soils changed only by 0.7 % and the content of agronomically valuable structures – only by 0.1 %, and in our experience – respectively by 2.1 and 1.4 % (towards improvement). The total soil permeability in the arable layer also decreased by 1.9 % in our study due to the use of flatcut tillage instead of fall plowing, while remaining within the acceptable range. Changes in the water regime related to the change in the method of basic soil cultivation could not negatively manifest at the level of productivity of crops cultivated in different experiments. In addition, only in fve publications out of 15 the reserves of available moisture in the root layer decreased due to replacing moldboard cultivation with non-moldboard loosening, and in the rest 10 ones they remained unchanged or they increased signifcantly. Therefore, the reserves of soil moisture available against the background of flat-cut loosening were 1.7 % higher in comparison with plowing. In the experiment, the advantage of flat-cut cultivation over plowing in terms of available moisture reserves in a meter layer of soil at the middle and end of the growing season of spring crops increased to 6.1 and 6.4 %, respectively. The average productivity of crops cultivated in crop rotation against the background of flat-cut cultivation was signifcantly (by 9.0 %) lower in comparison with plowing. The reason for this could be almost a third (by 27–31 %) higher infestation of crops after the moldboard-free main autumn tillage. Key words: fve-feld crop rotation, physical condition of the soil, reserves of available moisture, crops weediness, crop yield.

The article presents the results of field experiments, where on the basis of podsolized heavy loamy chernozem the influence of replacement of mouldboard ploughing with nonmouldboard cultivation over top soil weediness, weediness at the beginning and end of spring crop vegetation and weed species composition before harve sting were studied. Investigation methods of main fall ploughing under spring crops of five-course rotation: soybeans–rape–wheat–flax–barley at the depths of 15-17, 20-22, 25-27 cm were conducted after post-harvest field tillage. Analysis of data on contamination of the top soil with weed seeds have shown that with the replacement of fall main mouldboard ploughing gwith nonmouldboard cultivation the figure before sowing of all crops withdifferent tillage depthat crop rotation average increased by 131-132%. It caused the increase of actual weed infestation of all crops and at the beginning and end of spring crop vegetationafter different depths of fall nonmouldboard cultivation compared with ploughing at crop rotation average it was 120–132 and 123-138%respectively. Species composition of weeds afterthe replacement of main fall mouldboard ploughing with nonmouldboard cultivation remained mainlyunchanged; although in rape plantings the proportion of white campion and early spring weed sincreased, in wheat plantings– wild mustard andscentless mayweed, insoybean plantings– late spring weeds, in flax plantings– white campion, and in barley plantings– scarlet pimpernel.

No abstract

characterized by a significant deficiency of precipitation and high temperature air conditions. The research material were the varieties of common bean provided by the National Center for Plant Genetic Resources of Ukraine [3] and hybrid combinations obtained as a result of intervarietal crossings. Sowing was carried out by the temperature regime of soil 10-12 °С at the depth of seeding and stable increase of average daily air temperature. The placement of the plots was consistent, the varieties were sown in a six-time repetition. The wide-row sowing with a width of rows of 45 cm was used. The total area of the plots was 1.35 m², and the account one is 1.0 m². Sowing was carried out with the seeding rate of 18 similar seeds per 1 linear meter, the standard was placed in 10 numbers. The general adaptability of the common bean varieties for the research years was determined by regression coefficient (b i ) and the stability variance (S і 2 ). Assessment of the morphological features variation was carried out by the variation coefficient (V, %). The ecological variation coefficient (Vе, %) was determined by the ratio of the average sign to its standard deviation. The determination of ultrastability (Nom) and agronomic stability coefficient (As) was made. Conclusions. As a result of the three year research, it was established that the highest resistance to bacteriosis had such varieties as UD0303601, UD0303526, UD0303543 and UD0303557. The varieties UD0303601, UD0303526 were resistant under adverse growing conditions; the highest resistance to bacterial wilding, including under adverse growing conditions, was provided by the varieties UD0300414, UD0301063 and UD0303543; according to the resistance to variegation the following varieties were selected: UD0303543, UD0303557, and UD0303610 (they were better under all growing conditions).