Minimum Tillage Systems Research Articles

Effects of different tillage systems, nitrogen and irrigation on growth indicators and water productivity of wheat (Triticum aestivum)

During 2015-2017, by using the strip split-split plot design and three line-source sprinkler irrigation systems, effects of 0, 90, 135, and 180 kg N ha-1 as urea, 3395, 3850, 4240, and 4610 m3 water ha-1 in conventional, minimum, and no-tillage systems were investigated to determine effects of tillage systems on the wheat (Triticum aestivum L) nitrogen and water requirements. Results indicated that the grain yield, component yield and water use efficiency were statistically significant across the tillage systems. Conventional tillage had the higher yield and water use efficiency followed by minimum tillage and then no-tillage. The highest grain yield in the conventional tillage system was achieved by combined application of 4610 m3 water ha-1 and 180 kg N ha-1 and in minimum tillage and no-tillage systems were achieved by combined application of 4610 m3 water ha-1 and 135 kg N ha-1. In all tillage systems, combined application of 3850 m3 water and 135 kg N per hectare is recommendable for the highest water use efficiency.

Potential Impacts of Soil Tillage System on Isoflavone Concentration of Soybean as Functional Food Ingredients

Soybean is an important natural source of isoflavones, but their concentration is likely to be influenced by external factors, such as climatic conditions and soil tillage systems. However, there is minimal information about the effects of such external factors on the isoflavone concentration in soybeans grown in Europe. Therefore, in this study, field experiments were established in Romania to investigate the potential impacts of three different soil tillage systems—conventional, minimum tillage and no-tillage—on crop yields and the isoflavone concentration of soybeans for three experimental years, 2014–2016. Our experimental results indicated that the soil tillage systems had little impact on the soybean yields each year. However, the 2016 yield was found to be higher than the 2014 and 2015 yields under all three soil systems. For every experimental year, the higher yield was recorded by the conventional system, followed by the minimum tillage system and no-tillage system under first weed control (weed control two (wct2): S-metolaclor 960 g/L, imazamox 40 g/L and propaquizafop 100 g/L). Likewise, the soil tillage system did not have a significant influence on the total isoflavone concentrations. Nevertheless, we noticed some variations in the individual isoflavone concentration (daidzin, genistin, glycitin, daidzein, genistein) in each year. Altogether, the minimum tillage and no-tillage systems may be employed as a suitable soil tillage system in soybean farming without an impact on the total isoflavone.

Bacterivorous Nematodes Correlate with Soil Fertility and Improved Crop Production in an Organic Minimum Tillage System

Reduced nutrient mineralization rates under minimum tillage are usually compensated by mineral fertilizer application. These, however, cannot be applied in organic farming systems. We hypothesized that an organic minimum tillage system based on frequent cover cropping and application of dead mulch would improve soil fertility and compensate for the potential negative effects of minimum tillage. Two long-term field experiments were set up in 2010 and 2011 to compare plowing versus minimum tillage including the application of transferred mulch. A second factor, the application of compost versus mineral potassium and phosphorus, was also compared. In 2019, soils were analyzed for soil pH, organic carbon, macro- and micronutrients, microbial biomass, microbial activity, and total nematode abundance. In addition, performance of pea in the same soils was determined under greenhouse conditions. Across both experiments, macronutrients (+52%), micronutrients (+11%), microbial biomass (+51%), microbial activity (+86%), and bacterivorous nematodes (+112%) increased in minimum tillage compared to the plow-based system. In the greenhouse, pea biomass was 45% higher in the soil that had been subjected to minimum tillage compared to the plow. In conclusion, soil fertility can be improved in organic minimum tillage systems, which include intensive cover cropping and the application of dead mulch, over plow-based systems.

Effects of tillage systems on wheat and weed water relationships over time when growing together, in semiarid conditions

AbstractWater availability directly influences interactions and competition between weeds and crops. This article is based on the idea that relative water content (RWC) indicates the water uptake within plants and that it is possible to explain the water relationships between plants that are growing together. A field experiment carried out for 3 years (2013–2014, 2014–2015 and 2015–2016) compared the short‐term effects of years and tillage systems on wheat grain yield, weed density, wheat‐RWC, weed‐RWC and soil water content (SWC), at tillering and flowering stages in a winter wheat monoculture system. The three tillage treatments were conventional tillage (CT), minimum tillage (MT) and no‐tillage (NT). Wheat grain yield was low all years of study, because of low interannual rainfall, and we did not observe differences between tillage systems. Weed density was also affected by year and not by tillage systems. Lowest winter rainfall (73.4 mm from Nov to Feb) in the last year of the study (2015–2016), decreased the weed density in all tillage systems. Despite the rainfall variability over the 3 years of study, the NT system presented higher weed density (73 plants/m2) than MT and CT systems (39.83 and 46.33 plants/m2). We also observed a higher number of weed species for the NT system, facilitated by a high soil water storage in this system. The wheat‐RWC, at tillering stage, varied with years and tillage systems; we found that high winter rainfall (2013–2014) led to higher values in CT (64.5%) compared with MT (52.9%) and NT plots (52.9%). Weed‐RWC values did not vary and SWC was greater in NT than in CT and MT. At flowering stage, the year (2015–2016) with highest spring rainfall favoured higher wheat‐RWC in NT (56.9%) compared with CT (48.3%). However, the lowest spring rainfall coincided with the lowest weed‐RWC, (18% in NT plots) and SWC was always higher in NT soils. The results showed that climatic conditions affected the water competence dynamics between weeds and wheat in different ways. Seemingly, weeds can tolerate a lack of water availability until crop tillering stage independently of tillage system; however, the competition for water was not a problem as crops overcame the high weed density by flowering stage.

Weed infestation of soft spring wheat crops depending on the soil tillage system

The paper presents the results of the study on the influence of various tillage systems on the weed infestation of soft spring wheat of the Siberian Alliance variety. The study was carried out in a long-term stationary experiment (20152019) preceded by bare and green-manured fallow (rapeseed, melilot) in Kemerovo region. The soil of the experimental plot is classified as leached, medium-textured, medium-humus, heavy-loam chernozem. The following soil tillage systems were studied: deep moldboard, deep combined, minimum combined and minimum moldboard. Weather conditions during the research period were varied. Insufficient water supply during the first vegetation period of soft spring wheat (seedlings – leaf-tube formation) was noted in 2015-2017, with HTC (hydrothermal coefficient) being from 0.37 to 0.56. Excessive water content was observed in 2018 (HTC = 2.41) and moderate hydration – in 2019 (HTC = 1.12). Weed infestation was different in the conditions of each year. The impact of the soil tillage system on the number of weeds during the growing season of common spring wheat accounted for 21.6-90.4%, and their share in the total aboveground mass of the phytocenosis was 39.9-68.3%. The segetal flora in soft spring wheat crops is represented by monocotyledonous and dicotyledonous species with all the studied tillage systems. The highest density of weed vegetation during the tillering phase of soft spring wheat was recorded with deep moldboard soil tillage system (control). A reduction in weed infestation by 2.3 times compared to the control was noted with minimum moldboard soil tillage system preceded by bare fallow, 1.6 times – preceded by green-manured fallow with rapeseed, and 1.7 times – preceded by green-manured fallow with melilot. The same trend was observed in the proportion of weeds in the total aboveground mass of the phytocenosis during the wax ripeness phase of soft spring wheat with deep moldboard tillage system (4.3%), deep combined (3.9), minimum combined (4.1), minimum moldboard (2.6%).

Sustainability of quantitative and qualitative indicators of sugarcane production under different tillage systems (case study: Khuzestan province of Iran)

Increasing tillage operations and their repetition each year often increases the costs and adverse effects on soil physical properties. Rising fuel costs and high initial investment in the purchase of agricultural machinery and equipment, and the insistence on overuse of machinery in agriculture, have caused widespread concern around the world. Furthermore, traffic and additional operations by agricultural machinery are significant concerns. This study was performed at Hakim Farabi Sugarcane Agro-Industrial Company (HFSAIC) in Khuzestan province of Iran. The aim of this study was to assess the effect of different tillage systems on the quantitative and qualitative indicators of sugarcane production. The experiment was conducted as a completely randomized design (CRD), with four treatments including: 1- first-time subsoiler (D8 bulldozer) ​+ ​second-time subsoiler (D8 bulldozer) (conventional operation) 2- Alpego tillage tool 3- Nardi tillage tool 4- subsoiler for the first time (D8 bulldozer) ​+ ​subsoiler five Sheng. The result of analysis of variance showed non-significant differences in most quantitative and qualitative indicators in tillage systems. Analysis of mean comparison in quantitative and qualitative indicators showed that T 2 treatment (Alpego tillage tool) as a minimum tillage system, was a better system among different tillage systems in sugarcane cultivation. Generally, selecting the appropriate tillage system according to the climate conditions of the area and available equipment tools, along with appropriate solutions such as minimum tillage, can be one of the management practices in sugarcane cultivation. • This study was to investigate the quantitative and qualitative indicators. • Assessing the effect of different tillage treatments on sugarcane production. • Alpego tillage treatment is one of the best systems for increasing sugarcane yield. • Conservation tillage systems can prevent erosion by covering the plant residue.

Residue retention promotes soil carbon accumulation in minimum tillage systems: Implications for conservation agriculture

Crop residue retention and minimum tillage (including no–tillage, NT, and reduced tillage, RT) are common conservation tillage practices that have been extensively applied for improving soil health and reducing the negative environmental impact caused by intensive farming. However, the effects of minimum tillage, coupled with crop residue retention (including no–tillage plus residue retention, NTR, and reduced tillage plus residue retention, RTR), on soil organic carbon (SOC) stock have not been systematically analyzed. Using a dataset consisting of 1928 pairs of data points from 243 studies, we conducted a global meta–analysis to evaluate the effects of crop residue retention and minimum tillage on SOC stock in the 0–30 cm soil and how these effects varied with soil (soil sampling depth and texture), environmental (climate) and crop management conditions (cropping intensity), as well as treatment duration. We found that regardless of the climatic condition, crop management, or residue retention, minimum tillage alone increased the overall mean SOC stock. Specifically, NT and RT increased SOC stock by 11 and 6%, respectively, in comparison to conventional tillage (CT). Compared with CT, NTR and RTR increased SOC stock by 13 and 12%, respectively. The above effects were greater in the topsoil (62% of data points from the 0–15 cm depth) than in the subsoil (38% of data points from the 15–30 cm depth). Moreover, residue retention enhanced the resistance of SOC turnover to agricultural and environmental factors; mean annual temperature (coefficient = 0.15), soil pH (0.14), and experimental duration (0.08) were critical for increasing SOC stock with minimum tillage alone, while the response ratio of SOC stock under coupled residue retention and minimum tillage was insensitive to changes in those factors. Additionally, double cropping generally increased SOC stock cross all conservation tillage practices compared to multiple cropping. Therefore, we conclude that minimum tillage coupled with residue retention in a double-cropping system is the most promising management system for increasing SOC stocks in the 0–30 cm soil in croplands Our finding can inform sustainable soil management practices aimed at increasing resistance of SOC in croplands to climate change and soils degradation induced by intensive agriculture.

The effects of soil tillage techniques on weed flora in high input barley systems in northern Spain

In barley cropping systems of northern Spain, agronomic practices and weather conditions are key components of weed control efficacy. We compared the short-term effects of conventional tillage with minimum tillage (MT) and zero tillage (ZT), in barley monoculture and barley rotation systems. Weed density and weed species number were measured at tillering and flowering barley stages. We found that tillage system can influence weed density and weed species establishment due to, in part, the available light for weed seeds. The results obtained indicate that the MT system facilitates the prevalence of the grass weed Bromus diandrus Roth (50.37%) and the annual dicots Galium aparine (L.) and Buglossoides arvensis (L.) I.M. Johnst. abundant were high in the MT system too, 43.71% and 43.97% respectively. The germination of these species showed a high dependence on light availability. We saw that barley-monoculture plots had a large infestation of Bromus (71.29%) and barley-rotated plots presented more infestation of Galium and Buglossoides (74.36% and 84.4%, respectively). After herbicide application, weed infestation in conservation systems was reduced in barley-rotated plots compared with barley-monoculture. If conservation systems avoided the presence of dominant weeds, the weight of each weed species was balanced within competitive relationships of the cropping systems. Our results confirmed that MT and ZT systems favour different weed species emergences in barley-rotated plots. The combination of MT and barley-rotated cropping system resulted in greater weed diversity and lower total weed density.

Evaluation of Organic Camelina Crop Under Different Tillage Systems and Fertilization Types Using Proximal Remote Sensing

A field experiment was conducted in Southern Greece to assess Normalized Difference Vegetation Index (NDVI) and Red-Edge Normalized Difference Vegetation Index (NDRE) in estimating Camelina’s crop growth and yield parameters under different tillage systems (conventional and minimum tillage) and organic fertilization types (compost, vermicompost and untreated control). A proximal canopy sensor was used to measure the aforementioned Spectral Vegetation Indices (SVIs) at different days after sowing (DAS). Camelina presented the highest values of NDVI and NDRE under compost fertilization (0.63 and 0.22 accordingly) and minimum tillage system (0.50 and 0.18 accordingly). Additionally, the highest correlations between the measured crop parameters and NDVI, NDRE were achieved at leaf development to early flowering stage. Moreover, NDRE presented the highest correlation with seed yield (R2=0.60, p<0.05) and thus it is suggested for estimating Camelina’s productivity instead of NDVI. Finally, further research is needed for adopting the use of remote sensing technologies on predicting Camelina’s crop growth and yield.

Agronomic performance and severity of common rust in maize under different nitrogen sources

Nitrogen is the most required and complex management element in maize crop, promoting the highest responses in crop yield. The objective of this work was to verify the effect of different N sources on topdressing in minimum tillage and conventional tillage systems on the agronomic performance of the Pioneer 32R22YHR single cross and on the severity of common rust disease. Two experiments were carried out in a randomized block design (DBC) in the 2013/14 crop in minimum tillage and conventional tillage systems. The treatments were: control without nitrogen, ammonium sulfate, urea, ammonium nitrate, a physical mixture of nitrate (70%) and ammonium sulfate (30%) and a chemical mixture of these same sources in the same proportion just explained. Nitrogen sources had no significant effect on plant height, ear insertion height, ear prolificacy, grain yield and leaf severity of common rust, regardless of the sowing system. Under conventional tillage, the plants presented higher plant height, ear insertion and grain yield. There was no effect of sowing systems on prolificacy. With the exception of nitrogen free treatment, for all others, the severity of common rust was higher in minimum tillage system.

May conservation tillage enhance soil C and N accumulation without decreasing yield in intensive irrigated croplands? Results from an eight-year maize monoculture

Intensive management of agroecosystems has been widely indicated as major responsible for soil degradation, thus negatively impacting on relationships between agriculture and climate change. Conservation tillage (i.e. no-till and minimum tillage) has been recommended for enhancing soil organic carbon (SOC) and total nitrogen (STN) stocks while having a positive impact on food security, biodiversity, water quality and the environment. Nevertheless, positive responses were mainly reported in hot and semiarid climates, with rainfed crops and low N fertilization rates.Therefore, the main objective of this study was to test the adoption of conservation tillage in intensive maize cropping systems under temperate soil, with high N fertilization rate (> 200 kg N ha−1 yr−1) and organic matter input (i.e. manure distribution and high biomass return), and with permanent optimum water moisture due to irrigation. We conducted an 8-year field experiment on a maize (Zea mays L.) monoculture to assess: (i) the effect of no-till (NT) and minimum tillage (MT), on grain yield and biomass return as compared with conventional tillage (CT); (ii) how tillage systems affect the evolution of SOC and STN levels over time under these conditions; (iii) soil aggregation processes and mechanisms leading to SOC and STN changes in the long-term. Results showed that MT increased maize grain yield (+7 %) and total biomass (+10 %) compared with CT. Conversely, NT reduced maize grain and biomass production during the initial 5-year transition, but afterwards increased maize yield up to that of CT.At the end of the experiment, SOC sequestration was increased under NT and MT by 1.45 and 1.52 Mg C ha−1 yr−1 compared with CT, respectively. Also, STN accumulation was higher under NT and MT than under CT (+0.15 and +0.17 Mg N ha−1 yr−1, respectively). Most of such a SOC and STN increase was located into C- and N-rich macroaggregates. Within those macroaggregates (large macroaggregates, LM; small macroaggregates, sM), we found that C and N pools associated to mM accounted for between 41 and 65 % of total C and N content in NT and MT systems across the different soil layers, which is beneficial for long-term C and N stabilization in soils. Thus, introducing conservation tillage within intensive agricultural context devoted to maize monoculture as that of the Po Valley should be recommended to: (i) maintain (or even increase) maize yield, and (ii) enhance SOC and STN accumulation and stabilization.

Study of energy consumption and greenhouse gas (GHG) emissions in corn production systems: influence of different tillage systems and use of fertilizer

ABSTRACTThis study was carried out to evaluate the energy flow, GHG emissions, and global warming potential (GWP) in corn production in western Iran. The Data was collected by split plot Design based on randomized complete block design with four replications. The treatments consisted of a combination of three levels of the main tillage factor including conventional tillage (CT), minimum tillage (MT), no-tillage (NT), and three levels of chemical fertilizer including no fertilizer or N0P0K0 (NPK)0, N50P50K50 (NPK)50 and N100P100K100 (NPK)100. The results of this study showed that the total input energy in CT systems, MT, and NT was 56113.24, 51403.70, and 49144.45 MJ ha−1, respectively. The output energy in this tillage systems was 111989.11, 113312.80 and 109516.68 MJ ha−1 respectively. By reducing the rate of fertilizer, the amount of input and output energy was decreased. The NT and MT systems had higher energy efficiency than the CT one. Energy efficiency in (NPK)0, (NPK)50 and (NPK)100 was calculated to be 2.62, 2.53, and 1.88, respectively. The highest amounts of CO2, N2O, and CH4 were observed in corn production with CT systems. In no-fertilization treatments, GHG emissions were also lower. Moreover, the results showed that by decreasing tillage and increasing amount of fertilizer, GWP decreased. According to the results of this study, changing the practice of tillage from CT to MT and reducing fertilizer amount could increase energy efficiency in the region and reduce GHG emissions.

Minimum till lentil (Lens culinaris): an efficient way for rice fallow utilization and income enhancement in subtropical Tripura

Lentil (Lens culinaris Medic.) can be a potential crop to intensify the rice (Oryza sativa L.) fallow land of Tripura to meet out the pulses requirement of the state. Thus, five lentil varieties, i.e. HUL-57, WBL-77, WBL-58, PL-06 and NDL-1 were demonstrated under three establishment methods, i.e. minimum till (MT), no-till (NT) and paira cropping (PC) on 75 farmers’ field at Moracherra, Dhalai, Tripura during winter seasons of 2012–14 in a participatory mode to gear up the pulse production in the state. Study revealed that the cultivation of lentil under MT and NT systems resulted in more number of branches/plant, pods/plant, seeds/pod and seed yield than those planted under PC. Hence, the farmers planted lentil under MT obtained more gross and net returns than those planted lentil under NT and PC. However, benefit to cost (B:C) ratio was significantly higher under PC than the other establishment methods. Lentil variety HUL-57 outperformed other varieties with respect to number of branches/plant, pods/plant, seeds/pod, seed yield and also recorded the highest gross and net returns and B:C ratio followed by WBL-77, WBL-58. Therefore, study recommended the cultivation of lentil varieties HUL-57, WBL-77 and WBL-58 under minimum tillage system for intensifying the rice fallows of Tripura to boost up the pulses production in the state.

The Influence of Tillage System on Weeds and Maize Yields, in Different Pedoclimatic Conditions of Transylvanian Plain, During 2007-2018

Among the technological factors that contribute to the yield of maize, the fight weeds is a mandatory requirement. In 2007, a factorial yield test was performed at the Agricultural Research and Development Station (ARDS) Turda, where was studied the influence of the two systems, the classic (CS) and the minimum tillage one (MT) on the weeds and the yield maize, for a period of 12 years. Generally the total number of weeds in MT was higher (343 pcs. m-2 ) than CS (324 pcs.m2), because, without soil inversion, weed seeds remained in the soil surface layer where climate conditions stimulated weed germination. The cultivation of maize in minimum tillage system could be recommended as a viable alternative to the classical system in the hilly area from Transylvania, this recommendation is also based on the rather small quantitative differences (133 kg ha-1 ) between the two tillage systems.

SOIL PROTECTION STUDY THROUGH THE APPLICATION OF COMPLEX METHODS FOR SUSTAINABLE MANAGEMENT OF THE SOYBEAN AGROSYSTEM

"The degradation of natural soil fertility is caused by practicing the classic tillage system (ploughing with the furrow return) and using high doses of chemical fertilizers. It is necessary to adopt soil tillage techniques that aim to preserve and improve soil fertility without decrease production. In Romania, soybean crop, could be an economic boost for the agriculture sector because it reduces the costs required for the procurement of vegetable protein needed for the livestock and food sector, soybeans being a plant that fixes nitrogen from various sources (precipitation, activity of Bradyrhizobium japonicum bacteria, humus mineralization and residual nitrogen). From the research conducted between 2018-2020 at ARDS Turda, regarding the soybean root nodules cultivated in four tillage systems (CS - plough, MC - chisel, MD - disk and NT- direct sowing) with the technology specific to each system, the results indicate that in a conservative system the soybeans yield correlates positively with the number and weight of nodules formed. Organo-mineral fertilization (green fertilizer - autumn rape + gulle manure + N40P40) contributes significantly positively to the number and the weight of nodules and increases the yield. As an alternative to the CS, soybean can be cultivated in a minimum tillage system (MC), the yield difference compared to the classical system (plough) being insignificant, just 38 kg. The pedo-climatic conditions of the experimental area it is favourable for this crop and for the fixation of atmospheric nitrogen, without requiring high doses of mineral fertilizers."

Soil tillage to produce cassava roots with less physical limitations in pasture succession

Traditional cassava cultivation involves mechanical manipulation of the soil with one plowing and two harrowings, a practice that may generate problems such as soil erosion, compaction and nutrient loss. These issues may be even bigger in sandy soils. The objective of this study was to evaluate the cassava roots components and the soil physical attributes in planting rows and between planting rows in tillage systems substituting the conventional tillage before the Mombasa grass pasture (Panicum maximum), in Northwestern Paraná, Brazil. Soil tillage treatments in 2014 were carried out as follows: conventional (disc harrow, moldboard plow and disking), minimum (disc harrow and chisel plow - clod breaking) and zero tillage. In 2015, soil samples were collected in layers 0.0-0.1, 0.1-0.2 and 0.2-0.4 m deep, between, and within cassava planting rows, for soil bulk density and macroporosity determinations. Number of plants, number of tuberous roots per plant, fresh and dry mass of cassava tuberous roots were evaluated as well. The soil physical attributes within the planting rows negatively affected the production of cassava tuberous roots in zero tillage in succession to the Mombasa grass pasture. The minimum and conventional tillage systems did not present soil physical limitations to the cassava yield components in succession to Mombasa grass pasture. Minimum tillage may be an alternative to conventional tillage without compromising soil physical attributes and cassava root yield in the Mombasa pastureland reform areas, in northwestern Paraná.

Validation of the utilization of a specific spray machine to apply general herbicide (Glyphosate) for controlling weeds in chickpea farms in dry land areas of Iran.

Weeds are a serious problem of chickpea cultivation in rain-fed areas of Iran and economic feasibility of crop production is mostly challenged by the method of control. In this study, two types of weed control strategies which are common in the country, including hand removing and hand removing + mechanical application, were compared with application of general herbicide (Glyphosite) using a specific spray machine under a minimum tillage system. The trial was carried out in the farms of five ha each, along with a two-ha weedy control at Dry land Agricultural Research Institute (DARI), Maragheh, Iran during cropping season 2018-2019. Chickpea cultivar “Adel” was sown under no - tillage system in planting arrangements of 17.5 × 52.5 cm using a direct drill machine followed by routine operations such as pesticide or fertilizer applications during the growth season. Three patches of 10 m2 of each treatment were randomly chosen as blocks and measurements were conducted on four randomly chosen 1 m2 samples as replications inside them. Data arranged as completely randomized blocks design were analyzed. Results showed that although higher yield indices belonged to hand removing or hand removing + mechanical applications, a powerful economic feasibility could be obtained by application of Glyphosate using the spray machine. It may be inferred from this study that in the absence or under situations where application of selective herbicides is non-economic, farmers can apply relatively in-expensive general herbicides to control weeds using this machine and gain acceptable income.

The Influence of the Tillage System and Fertilization on Soybean Yield at ARDS Turda, 2015-2017

Soybean is currently one of the most important agricultural crops being used in human and animal nutrition, as a raw material for industry but also has agro-phyto-technical importance because it contributes to the raising of soil fertility by fixing atmospheric nitrogen by symbiosis between soybeans and Rhizobium japonicum bacteria, which forms root-nodules. To achieve the aims, a poly-factorial experience has been placed during the period 2015-2017 at ARDS Turda, with the factors: Factor A - the tillage system (a1 the classical tillage system by plowing with the return of the furrow and a2 the minimum tillage system, chisel variant; factor B- the fertilization (b1-N20P20K0 100 kg/ha, applied simultaneously with sowing, b2-N20P20K0 100 kg/ha, applied simultaneously with the sowing + N20P20K0 100 kg/ha, applied in the 4-6 leaves phenophase, b3-N20P20K0 100 kg/ha applied simultaneously with sowing + N30 100 kg/ha, applied in the 4-6 leaves phenophase and b4-N20P20K0 100 kg/ha applied simultaneously with sowing + N20 100 kg/ha, applied in the 4-6 leaves phenophase, factor C-climatic conditions in the experimental years (c1-2015; c2-2016; c3-2017). The soybean variety studied was Malina TD. Following the application of the minimum tillage system, the yield decreases with a significant difference of 86 kg/ha compared to the conventional tillage system. A very significant influence in the yield of superior quantitative yields is fertilization, in the three variants where the supplementary fertilization was applied, there were obtained very significant yield increases of over 199 kg/ha compared to the control variant which produced a yield of 2373 kg/ha.

Influence of various systems of soil tillage on agrophysical properties of leached chernozem

The paper presents the results of research into the effect of different soil tillage systems on soil density and structure. The research was conducted in a long-term stationary experiment on the crops of Nikita spring barley. The soil of the experimental plot is classifi ed as leached, mediumtextured, medium-humus, heavy-loam chernozem. The following soil tillage systems with peas as a forecrop were studied: deep moldboard, deep combined, minimum combined and zero. The years of research (2015-2018) differed in heat availability and amount of precipitation. This allowed to study and carry out comparative assessment of the effect of various soil tillage systems of leached chernozem on agrophysical properties of soil. Yearly weather conditions had no signifi cant effect on soil density with all the studied soil tillage systems in single and binary crops of spring barley, whereby the indicators varied from 1.87 to 6.72%. Compared to deep moldboard tillage (control), there was an increase in soil density with zero tillage in singlecrop sowings of spring barley by 6.2%, and in binary crops – by 9.4%. However, the indices were not beyond optimum values of 1.02-1.05 g/ cm3. The optimum equilibrium soil density for the main subtypes of chernozems is 1.0-1.25 g/cm3. Minimum combined soil tillage system resulted in the stable content of valuable structural soil units 0.25-10 mm both in single-crop and binary sowings of spring barley at 68.3% and 68.9%, and the coeffi cient of soil structural properties – 2.15 and 2.21 respectively. It was established that the effect of soil tillage system on the creation of valuable structural units in soil was 21.4%, yearly weather conditions – 11.8%, type of crops – 25.5%.

Residue retention and minimum tillage improve physical environment of the soil in croplands: A global meta-analysis

Conservation tillage practices, here defined as no-tillage (NT) or reduced tillage (RT) with/without residue retention, have been widely used to alleviate the negative effects caused by intensive tillage practices. Implementing effective and sustainable agriculture requires a deeper understanding of the impacts of conservation tillage practices on soil physical properties. This study examined the effects of conservation tillage practices on soil physical properties, including soil bulk density, aggregate size and stability, hydraulic properties, and soil pH; based on data collected from 264 studies published worldwide since 1980. The results indicated that no-tillage (NT), NT with residue retention (NTS), and reduced tillage (RT) increased bulk density by 1.4, 2.6, and 2.1%, respectively, compared with conventional tillage (CT). Soil bulk density decreased by 2.9% in NTS compared with NT, and 3.9% in RT with residue retention (RTS) compared with RT. The effect size of bulk density significantly decreased with the increasing experimental duration under NT and NTS practices. Compared to CT, conservation tillage practices increased aggregate mean weight diameter (MWD), geometric mean weight diameter and water stable aggregate (WSA) regardless of the residue retention or minimum tillage systems. The largest effect size of MWD (51.9%) and WSA (54.9%) appeared under NTS as compared to the CT. The effect size of MWD and WSA increased under NT with the increasing experimental duration. NT increased saturated hydraulic conductivity by 24.6% compared to CT. All conservation tillage practices increased soil available water capacity (AWC) compared with CT and NTS with a 10.2% increase in AWC compared with NT. The effect size of AWC increased under RT and NT practices with the increasing experimental duration. Soil pH decreased by 1.7 and 1.0% under RTS compared with RT and CT, respectively; and NT led to a 2.8% reduction in soil pH compared with CT. The effect size of soil pH decreased under RT and NT treatments with the increasing experiment duration. Overall, conservation tillage practices positively affected many soil physical properties; and the extent of the effects varied with the duration of the experiment.