Optimizing Crop Rotation and Cereal Saturation for Sustainable Winter Wheat Production Under Semiarid Conditions of Uzbekistan

The purpose of the research is to establish the influence of the structure, content and placement of field crops in 6-7-field crop rotations on their overall productivity, yield and quality of winter wheat in particular. Methods. The technology of growing agricultural crops in the experiment is generally accepted and recommended for the research area. Chemical plant protection agents were used to grow competitive commercial products of winter wheat. Results. The results of research conducted in a long-term stationary field experiment, which was established in 2001, on the study of crop rotations on typical chernozems of unstable moisture in the Left Bank Forest-Steppe during 2016–2021 for six-field and 2016–2022 for seven-field crop rotations, convincingly indicate that the most rational in this subzone was a 6-field crop rotation saturated with winter wheat by 16.7% (soy – winter wheat – sugar beets – spring barley – corn for grain – buckwheat) under the organo-mineral intensification system (predecessor by-products + N60P60K60). Conclusions. The grain yield of winter wheat, which was grown after soybean, buckwheat and winter rapeseed as predecessors under the appropriate set of crop rotations, was in the range of: 5.62–6.02 t/ha, while the protein content in the grain was at the level of – 12.66–13.67%. The economic efficiency of growing winter wheat in the structure of 6-7-field crop rotations was: conditionally net profit – 14.95–16.99 thousand hrn/ha at the level of profitability – 108–125%.

Purpose: to study the impact of fallow predecessors of winter wheat and fertilization systems on its productivity and quality, as well as on the yield of subsequent crop of sugar beet. Materials and methods. The research was conducted over 23 years in a field stationary experiment. The predecessors of winter wheat were black fallow, green manure fallow and sown fallow. Organic and organomineral fertilization systems were applied. In the first case, the following were carried out: 1) manure application – 6 t/ha of arable land (30 t/ha for winter wheat); 2) use of non-marketable part of the crop yield and green manure mass in fallow for fertilization. In addition to this, mineral fertilizers were applied on an organomineral background – N₁₈₅P₁₈₅K₂₀₀ per crop rotation, and N₆₀P₆₀K₆₀ and N₉₀P₉₀K₉₀ were applied for winter wheat and sugar beet, respectively, i. e. in this case the level of fertilizer application was higher. Results. After sown fallow, the average productivity of winter wheat, compared to bare fallow, decreased in the variant with the mineral fertilizers application by 20 %, without them – by 13 %. The advantage of bare fallow over green manure in terms of wheat grain yield was only on an organomineral background – by 0.27 t/ha. Replacing black fallow with green manure led to an increase in the yield of sugar beet, especially with an organic fertilization system. In all studied crop rotation links, the organomineral fertilizer system surpassed the organic one in productivity of both winter wheat and sugar beet. The quality of winter wheat grain decreased in the crop rotation with sown fallow and was practically the same in crop rotations with black and green manure fallow. Conclusions. The highest yield of sugar beet root crops over 23 years of research was obtained in the grain-fallow-row crop rotation with green manure fallow. The grain quality indicators of winter wheat were the highest and practically the same in crop rotation links with black and green manure fallow and lower in the link with sown fallow. The obtained result may indicate that in crop rotations of farms specializing in grain and sugar beet growing, partial replacement of black fallow with green manure is possible in the structure of sown areas, which will improve the state of soil fertility.

Increasing soil microbial biomass nitrogen in crop rotation systems by improving nitrogen resources under nitrogen application

Purpose. To find out the dependence of sugar beet and barley productivity in short crop rotations on organo-mineral fertilizer system and soil tillage with the use of manure and harvest residues (straw of cereals and sugar beet tops).Methods. Field, laboratory, and statistical.Results. The study was carried out in the area of insufficient soil moisture of the Left Bank Forest-Steppe of Ukraine on the slightly saline chernozem in a long-term stationary experiment in the following short crop rotations: crop rotation system esparcet + Festuca pratensis and grain-hoed crop rotation in the link with bare fallow with the 25 % share of sugar beet. Fertilization for the experiment was organo-mineral, both in crop rotation and under sugar beet. Barley was grown after sugar beet against the background of the aftereffect of fertilizers applied to sugar beet. The ploughing of harvest residues of all the crops of the rotation into the soil against the background of mineral fertilization was not inferior to the use of manure and mineral fertilization system by the effect on the sugar beet and barley yields.Conclusions. Under the application of 25 t/ha of manure + N90P90K90, in the crop rotatory system, root yield and sugar yields were 37.6 and 6.56 t/ha, respectively. To compare, in grain-hoed crop rotation, these values were 38.3 and 6.62 t/ha, respectively. When ploughing the crop residues of all crops in the rotation into the soil + N90P90K90, root yield in both crop rotation systems was at the level of the treatment 25 t/ha of manure + N90P90K90. Sugar beet productivity under the combined tillage in the grain-hoed crop rotation and all fertilization systems was not inferior to ploughing. Under the application of 25 t/ha of manure + straw in both crop rotation systems, root yield was 36.4 and 34.2 t/ha, respectively, and sugar yield was 6.13 and 5.81 t/ha, respectively. Barley yield in both crop rotation systems under the aftereffect of fertilizers applied to sugar beet + straw + N90P90K90 had advantages in the link with bare fallow compared to the link esparcet + Festuca pratensis. Barley yield under the combined soil tillage was not inferior to ploughing.

The results of the study of changes in winter wheat grain yield depending on the rotation length of crop rotations in the Lower Volga region are presented. As a result of 12 years of research (20082019) it was found that the maximum yield was obtained in four- and five-field crop rotations with the inclusion of leguminous crops - 2.73 and 2.79 t/ha, respectively. During the analysis of variance, different effects of growing conditions and rotation length on winter wheat yields were noted. The influence of vegetation conditions accounted for 98.6%. The effect of crop rotation was also significant (0.6%). Winter wheat grain yield significantly depended on the weather conditions, which allowed to fully evaluate the potential of winter wheat - fallow in crop rotations with a short rotation. When winter wheat was cultivated in four- and five-field crop rotations with the inclusion of leguminous crops, the yield increased both in wet and moderately wet years. With HTC greater than 0.9 in the five-field crop rotation the grain yield was 4.40 t/ha, in four-field - 4.31, in three-field - 4.02 t/ha. With HTC of 0.6 to 0.9 in four- and five-field crop rotations, the yield ranged from 2.78-2.84 t/ha, and in three-field crop rotations it was 2.52 t/ha. In dry years, no significant difference in winter wheat yield between crop rotations was found, which ranged from 0.98-1.07 t/ha. It can be concluded that winter wheat cultivation on the second field of short rotational crop rotations on fallow preceding crop in conditions of insufficient moisture is effective.

The effects of crop rotation, nutrient supply and plant protection technologies were examined on the yield of Mv PÁLMA winter wheat variety and on the most important diseases of ear and leaf. Our experiments were carried out on chernozem soil in the Hajdúság in 2006 and 2007, and three plant protection technologies (extensive, average, intensive) and three irrigation variations (without irrigation, irrigated with 50 mm, irrigated with100 mm) were applied in different crop rotation systems. In the triculture crop rotation a higher rate of infection was observed than in the biculture crop rotation, because the vegetative growth was more expressed after pea and these microclimatic factors were favourable for the development of pathogens.In the triculture crop rotation (pea – wheat – maize) the powdery mildew, DTR and leaf rust of wheat were present in both examined years (powdery mildew 5-15%, DTR 14-42%, leaf rust 8-37% in cropyear 2005/2006, powdery mildew 12-32%, DTR 9-29%, leaf rust 8-26% in cropyear 2006/2007). Fusaria could be observed in 2006 (depending on the plant protection technologies and nutrient supply in the biculture 7-27% and in thetriculture 5-19%). With higher amounts of fertilizers the rate of infection increased and reached its maximum at the highest dose of nutrient supply (N200 +PK).We observed the highest rate of infection by ear and leaf diseases in the case of the extensive technology, while this rate could be considerably reduced by the application of the intensive technology.Both in 2006 and 2007, yields were the highest at the N100-200+PK levels in the triculture after pea (6028-7939 kg ha-1 in cropyear 2006, 6578-8690 kg ha-1 in cropyear 2007 depending on plant protection technologies), and at the N150-200+PK levels in the biculture after maize (6096-7653 kg ha-1 in cropyear 2006, 4974-8123 kg ha-1 in cropyear 2007 depending on the plant protection technologies). The highest yield maximums werereached when pea was the forecrop. The yields on the experimental plots of the intensive plant protection technology was 224-2198 kg ha-1 higher (depending on the forecrop) compared to the plots where the extensive technology was used.The highest yield without irrigation was at the N150+PK both in biculture and triculture crop rotation. Among the irrigated variations Ö2 and Ö3 at N200+PK fertilisation resulted in the highest yield in the biculture crop rotation, while the N100+PK level in triculture system. In the biculture crop rotation the extra yield was 14-51% higher (575-1225 kg ha-1 depending on plant protection technology) when 50 mm water was irrigated, and15-54% higher (778-2480 kg ha-1) if 100 mm irrigation was applied comparing to the non-irrigated versions. The yield was 7-17% higher (560-1086 kg ha-1) in the Ö2 irrigation variation, and 8-23% (691-1446 kg ha-1) higher in the Ö3 irrigation variation compared to Ö1 irrigation variation (non-irrigated).A correlation analysis was made to reveal the connection between the yield, the amount of fertilizers, the rate of infection, the plant protection technologies and the forecrops. Strong positive correlation (0.846) was found between year and fusaria infection. Strong positive correlation was observed between fertilization and powdery mildew infection (0.525), fertilization and DTR (0.528), fertilization and yield quantity (0.683). Lowercorrelation was found between fertilization and leaf rust infection (0.409), and forecrop and yield (0.472), recpectively. Negative correlation was calcutated between plant protection technologies and DTR (-0.611), and plant protection technologies and leaf rust (-0.649).

The purpose of the current study was to identify the effect of various crop rotations and rates of application of mineral fertilizers on productivity of winter wheat and spring barley, the productivity of crop rotations and the economic efficiency of cultivating crops. The study was carried out in a stationary field trial of the FSBSI “Kursk FARC” on typical heavy loamy blackearth (chernozem) in 2015–2023. Agricultural crops were grown in three crop rotations: 1 – grainrow fallow (black fallow, winter wheat, sugar beets, maize for silage, barley); 2 – grain-row green manure fallow (green manure fallow, winter wheat, sugar beets, maize for silage, barley); 3 – crop rotation (horse-bean for grain, winter wheat, sugar beets, white lupine for grain, barley). During the trial there have been compared two contrasting levels of mineral fertilizer application N30Р30К30 and N52Р52К52 per hectare of crop rotation area. The non-marketable portion of the harvest of all crops was used as fertilizer. Agricultural technology was generally conventional for the area. There has been established that, under all weather conditions, the highest yield of winter wheat at a low background of fertilization (N30Р30К300 per hectare of crop rotation area) is produced in green manure fallow, and at a high background of fertilization (N52Р52К52 per hectare of crop rotation area) in black fallow. There was found that the most favorable conditions for cultivating barley were created when cultivating with white lupine for grain. Fertilization increase led to productivity increase of the grain crops, but, at the same time, to a production profitability decrease. There has been determined that productivity of crop rotations with fallow forecrops is 14 % higher compared to crop rotations with a legume forecrop (horse-bean for grain). According to calculations, on average over the years of study, the most profitable was the winter wheat cultivation in black fallow, and spring barley cultivation in white lupine for grain. At the same time, the indicator of production profitability level decreased with an increase in the rate of mineral fertilizing, which results in production costs’ increase.

Аіm. The research was to establish the influence of fertilization systems and methods of main tillage in short-rotation crop rotation on damage to winter wheat and pea plants by root rot. Methods. Field, analytical and statistical. The research was conducted in 2016–2018 at the experimental fields of the Bila Tserkva’s National Agrarian University according to the following scheme: Factor A. Fertilizer systems. 1. Without the use of fertilizers; 2. Organo-mineral; 3. Mineral. Factor B. Systems of basic tillage. 1. Differentiated (control); 2. Police-nonpolice; 3. Shallow shelfless. Short-rotation crop rotations were studied: crop rotation: alfalfa – winter wheat + white mustard, green manure – sugar beets and sunflower – buckwheat – barley with alfalfa subsowing; grain crops: soybean – winter wheat – sunflower – barley – corn for grain; specialized cereal crops: buckwheat – winter wheat – corn for grain, sunflower – barley – sunflower; row crops: peas – winter wheat – sunflower – corn for grain – sunflower. Results. During crop rotation with an organo-mineral fertilization system in the agrocenosis of winter wheat, the development of root rot was 51.3%, which is 8.7% more compared to the option without fertilizers. In the grain-row crop rotation under the organo-mineral fertilization system, root rot damage was 50%, which is 6.1% less compared to the unfertilized plot. Under the inter-row specialized crop rotation, the damage to winter wheat plants and the development of diseases amounted to 55.4%, which increased by 10.5% compared to the inter-row crop rotation. Affected pea plants by root rot in the flowering phase under shelf-less tillage, the development of the disease was 4.7% higher compared to differentiated tillage. Conclusions. The article presents the results of field studies on the application of fertilization systems and methods of basic tillage to the damage of winter wheat and pea plants by root rot in short-rotational crop rotations in the conditions of the Forest Steppe of Ukraine. The greatest damage to winter wheat plants by root rot was recorded during the row rotation, the predecessor of which was peas. On average, 32.6–37.6% of wheat plants were affected by the disease in these areas, and the intensity of the disease was 52.4–58.7%. The lowest development of root rots of winter wheat plants (27.4–35.4%) was found in the grain row specialized crop rotation. The smallest development of root rots of winter wheat plants was found under the organo-mineral fertilization system. Shallow cultivation with disc tools to a depth of 10–12 cm caused the highest development of pea root rot. Plowing under peas helped reduce the spread and development of pea root rot.

Efficient water management in agriculture is an important part of the general programme on water resources preservation. This study is devoted to the determination of the effects of soil processing system and mineral fertilization on the water use efficiency and productivity of grain corn (Zea mays Linnaeus, 1753). The trials were conducted in 2017–2018 on irrigated land in the South of Ukraine. The field experiments were carried out on the experimental plots of the Institute of Irrigated Agriculture of the NAAS in four replications. We studied the following agrotechnological parameters and their combinations: Factor A – primary tillage type and depth within different tillage systems in the short crop rotation (grain corn – grain sorghum – winter wheat – soybean); Factor B – application rates of mineral fertilizers (N0P0, N120P60, N180P60). We established that the highest yield of grain accompanied by the best water use efficiency was provided by the cultivation technology with disk cultivator tillage on the depth of 8–10 cm within the differentiated tillage system in the crop rotation under the maximum nutritive background of N180P60. This agrotechnological variant resulted in a corn grain yield of 14.51 and 14.59 t/ha in 2017 and 2018 years of the study, respectively. The coefficient of water use efficiency, which is the relation of the water used by the crop to the yield, in this variant was the lowest – 39.6 and 42.0 mm/t in 2017 and 2018, respectively, which indicates the optimum response of corn grain to watering. The worst indexes of water use efficiency and corn productivity were determined in the experimental variant with disk cultivator tillage on the depth of 12–14 cm within the subsoil tillage system within the crop rotation under non-fertilized conditions. We determined that strengthening of the crop nutrition under the rational tillage system in crop rotation is helpful in optimization of the crop water use in the irrigated conditions of the South of Ukraine, which is very important in the current conditions of freshwater scarcity.

Goal. To analyze results of long-term research in productivity of different short field crop rotations in conditions of left bank Forest-steppe of Ukraine. Methods. General scientific and special: long-term field — to determine quantitative performance metrics of short crop rotations, and analytical. Results. They determined the yield of crops in crop rotations, as well as the calculated productivity of different 4-filed rotations. The positive role is emphasized by leguminous predecessors for leading grain crop of Ukraine — winter wheat. It is revealed that the use of pea, lentil and vetch-oat mixture in the short crop rotation increases the yields of winter wheat and root crops of the 3rd culture of crop rotation — sugar beet. The influence of crop rotations on crop yield in the 4th year of the rotation (spring barley) is somewhat reduced. The role of fallow in the crop rotation is known. Numerous studies have established that in the conditions of insufficient and unstable moistening the best precursor for winter wheat is clean fallow. The fallow makes it possible to prepare the soil, retain enough moisture and nutrients in the form available to plants practically at any weather conditions. This helps to obtain high yields of winter wheat, but the productivity of the 4-field crop rotations with this precursor is greatly reduced. This primarily happens due to the lack of products in the field of clean fallow. Conclusions. In the conditions of unstable moistening of the left bank Forest-steppe of Ukraine on typical chernozem, the higher output of food-protein units was got in the crop rotations with soybean, pea, lentil and vetch-oat mixture. The worse indices were got in the rotation with Lathyrus sativus L. The low productivity had short crop rotations with silage maize and beans. Studies revealed a significant reduction in the productivity of crop rotation with a clean fallow. It provided minimal productivity due to the lack of production in the first field.

The article presents the study results of the field experiments on chemicals impact on phytosanitary conditions of crops and grain yield of winter wheat. Winter wheat was grown in a long-term crop rotation by the following scheme: potatoes, spring barley, pea- vetch-oat mix for green fodder, winter wheat. Phosphorus and potash fertilizers (P60K90) were applied as the background one. Nitrogen fertilizers in the form of ammonium nitrate were used on the experiment variants at the rate of N34.6 – N69.2 and N103.8. The herbicide Agritox, fungicide Alto and microelement cuprous sulphate were applied in ac-cordance with the scheme of the experiment. The statistical processing of experimental data proved that no harmful impact of pesticides on the productivity of winter wheat was observed in the years of the weak development of weeds and harmful phytopathogens. Regulating the phytosanitary condition of crops due to the winter wheat in the crop rotation, and the application of the herbicide Agritox at the rate of 1.5 kg/ha and the fungicide Alto (250 g/ha) and cuprous sulphate (350 g/ha), it is possible to achieve the planned level of winter wheat yield of 5.37-5.95 t/ha. The combined effect of nitrogen fertilizers and plant protection chemicals allows a differentiated approach to the role assessment of each studied factor de-pending on weather conditions. It has been revealed that the optimal combination of the applied means of chemicalization in the crop rotation system ensures the implementation of the planned level of grain yield of winter wheat in the range from 5.37 to 5.95 t/ha.

RCP情景下长江中下游麦稻二熟制气候生产潜力变化特征研究

An exact experiment, established in a system of randomized blocks, was aimed at determining the effect of crop rotation and 29-year cereal monoculture on the yield and quality of winter wheat grain as well as on straw yield, crop infestation with weeds, contents of organic C and total N in the soil, and the number of earthworms in the soil. Winter wheat was sown in two systems of crop succession: (1) in crop rotation (CR), and (2) in a cereal monoculture (CM). Winter wheat cultivation in the CM system resulted in a decrease of grain yield by 32%, compared to the CR system. Its grain yield reduction in the CM system was due to a lower number of spikes m−2, lower 1000 grain weight, shorter spikes, and lower grain weight per spike, than in the CR system. Wheat grain from the CM system was characterized by a lower content of wet gluten, lesser grain uniformity and grain volume weight, and contained more total ash than the grain from the CR system. The number and air-dry weight of weeds were higher in the CM than in the CR system by 57.1% and 75%, respectively. Differences were also demonstrated in the species composition of weeds. The soil samples collected from the CM plot contained less organic C and total N than the samples derived from the CR system. Soil samples from the CM system had also a lower number of earthworms compared to the CR soil samples.

The objectives of this research are: 1) To compare the factors of land tenure, ecological aspects, economic conditions, perception of information and wisdom affecting the selection in highland rotation cropping and mono cropping. 2) To analyze and identify differences in land management between highland rotation cropping and mono cropping. And 3) to analyze and assess the link between the intensive highland rotation cropping and mono cropping with soil management and degradation. There were quantitative and qualitative data collections from farmer groups of both systems by using the tools as questionnaires and in-depth interviews with participant observation including exploring the research area plot. The data were analyzed using descriptive statistical method in the form of frequency distribution, percentage and comparison table. The results showed the land tenure of the two highland cropping systems was not different. There were no documents and rights over the lands. Rotation cropping system focused on intensive commercial agricultural production, whereas mono cropping system focused on subsistence. Both systems used traditional wisdom. The characteristics of rotation cropping were separated rotation cropping with legumes and no legumes, so crops could be grown throughout the year and continuously. Therefore, the soil management was intensive and the soil was not time for resting. The characteristics of mono cropping system involved growing only one type of crop every other year and year after year. There was a one-year soil resting and the mono crops were replanted annually, so there was not the soil resting. There are differences in the use of chemical fertilizers and concentrated chemicals, as well as soil fertility. It could be concluded that both of cropping systems were not different and had moderate fertility The soil erosion in rotation cropping system was very low to moderate level, thus soil condition was sustainable. The soil erosion in mono cropping system was low to very severe level, thus soil condition was not sustainable.The policy and action recommendations, the government should support in terms of alternative agricultural policies and budgets for developing highland areas seriously and comprehensively in accordance with the sufficiency economy.

Purpose. To substantiate the energy efficiency of various crop rotations as affected by a system of fertilization, energy removal with harvest and energy costs.Methods. The measure of energy efficiency of crop cultivation technology is the energy efficiency ratio, which expresses the ratio of the total energy content of the cultivated crop to the amount of non-renewable energy spent on its cultivation.Results. The research was carried out in the stationary experiment on typical leached chernozem in the zone of unstable wetting in six-course multivariate crop rotation: crop rotation (33% fodder crops, 17% row crops, 50% grain crops), row crop rotation (17% fodder crops, 50% row crops, 33% grain crops) and grain-row crop rotation (17% fodder crops, 33% row crops, 50% grain crops). The experiment has shown that against the background of 16.6 t/ha of manure + N53.3P53.3K53.3, the energy removal with the harvest in the link of crop rotation amounted to 319169 MJ, in the link of row crop rotation 292569, and in the link of grain-row crop rotation 301963 MJ, which was by 48, 44 and 48%, respectively, higher than the energy removal against the background without fertilization. The energy efficiency ratio (kee) had the highest value in grain-row crop rotation (4.39), while in the crop rotation and grain-row crop rotation 4.03 and 3.97, respectively. In fertilized crop rotation, the yield of energy from the crop was at the level of the organic-mineral fertilizer system in treatments of ploughing-in crop residues against the background of mineral fertilization. High fertilizer rates applied in grain-crop rotation increase the yield of energy removal with the crop. The reduction of fertilizer rates significantly reduces both the energy removal and the efficiency of energy.Conclusions. The highest yield of energy with the crop (319169 MJ) was recorded in crop rotation in the link of oat – winter wheat – sugar beet at the background of application of 16.6 t/ha of manure + N53.3P53.3K53.3. Ploughing- in crops residues against the background of the mineral system provides a yield of energy with a yield of 303534 MJ at kee 4.06, which is at the level organic-mineral fertilizer system. High fertilizer rates applied in grain-seed crop rotation increase the yield of energy with the yield, but kee does not exceed 4.31–4.33. The reduction of fertilizer rates significantly reduces both the energy removal by crop and the energy efficiency ratio.