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Field experiments were conducted to investigate the effects of residue and tillage on growth and yield of melon. Tillage treatments included conventional tillage (using a moldboard plough and two passes with a disk harrow), minimum tillage (one pass with a disk harrow), and no tillage (NT). Residue treatments included the application of 0%, 30% and 60% residue. Yield and yield components were obtained for all treatments. Tillage significantly affected yield and its components (P ≤ 0.05). The maximum FWPP (2.678 kg), NFPP (6.799), D (18.49 cm), L (45.93 cm), S (12.51%) and RUE (2.470) and yield (16.17 t/ha) were recorded in the conventional tillage treatment. Also, maximum FWPP (2.192 kg), NFPP (5.353), D (16.66 cm), L (39.52 cm) and yield (12.83 t/ha) were observed in the 30% residue treatment. In terms of the interaction effects, maximum FWPP (2.850 kg), NFPP (6.790), D (20.71 cm), L (53.53 cm) and yield (17.09 t/ha) were obtained in the conventional tillage + 30% residue treatment. Therefore, the use of a moldboard plough followed by two passes with a disk harrow, in concert with 30% residue treatment, were maximizing the yield Almost all growth indicators had the optimum values in the conservation tillage treatments.

Tillage is one of the most important operations in the preparation of land for growing crops. Among secondary tillage implements, power harrows, which have a series of PTO-driven rotors which rotate about their vertical axis, are widely adopted in soil-working operations. Typically, this kind of implement is highly energy consuming, due to the heavy mechanical loads required to pull the harrow and the PTO (Power Take-Off) torque needed to drive the rotors. This paper reports the results of extensive in-field experimentation in which the relationship between the operating conditions of a tractor - power harrow system and the mechanical loads (i.e. PTO torque and draught) were investigated in two different test site fields. The test parameters consisted of: nominal tractor speed (3, 6, 9 and 12 km h−1), nominal working depth (6, 9 and 15 cm) and rotor speed (285 and 411 rpm) at a PTO speed of 1000 rpm. The data was statistically analysed by means of a linear mixed effect model to assess the differences in the tractor - harrow system performances measured under different working conditions. The presented results show which operating conditions can be favourable regarding energy and fuel consumption as this information may be very useful to farmers to reduce costs. Moreover, the measured mechanical loads concerning PTO torque and draught may also be beneficial for manufacturers to improve the design of these kinds of implements.

The intensive use or discontinuation of the use of swards can compromise biodiversity, yields, and feed quality; thus, leading to the degradation of permanent grasslands. Various methods of renovation are employed to restore the usability of degraded swards. In the years 2013–2016, a monofactorial field experiment was carried out on the Experimental Farm in Grabów (province of Mazowieckie, Poland). The experiment involved swards being reseeded after ploughing (P) and after disking with a compact harrow (H), with a non-renovated sward as the control treatment. The plots under renovation were reseeded with a lucerne–grass mixture. Both seedbed preparation methods for the renewed sward, ploughing (P) or shallow disking to a depth of 5 cm (H), were found to be effective for increasing sward yields, restricting weed growth, and reducing the number of weeds in the sward. The ploughing-based renovation method (P) had a strongly restrictive effect on biodiversity, as expressed by the H’ function value vis-à-vis the harrow method (H) and the non-renewed control (NR). Dicotyledonous species accounted for 92.3% of the weed population in the studied treatments. Of these, Taraxacum officinale, Achillea milefolium, Capsella bursa-pastoris, and Plantago maior occurred in the highest numbers.

The spring-tine harrow is gaining popularity for mechanical weeding. However, its weeding performance and mechanism have not been well understood. A spring-tine harrow was first tested in a controlled indoor soil bin at four different travel speeds (4, 6, 8, and 10 km h−1) with three different spring-loading settings (low, medium, and high). Then the harrow was tested in a wheat (Triticum aestivum L.) field at the same spring-loading settings at three different weeding timings (early, middle, and late) in 2019 and 2020. Soil cutting forces (draft and vertical), soil displacements (forward and lateral), soil working depth, weed control efficacy, weed density, and crop damage were measured. The results showed that the spring-loading setting had a more dominant effect on working depth and soil cutting forces than the speed. The soil displacements were more dependent on the speed compared with the spring-loading setting. Treatment effects on weeding performance indicators in the field were similar across years. Adjusting the spring-loading setting from low to high improved the weeding efficacy from 44.9% to 73.9% in 2019 and from 51.6% to 78.1% in 2020. Consequently, the final weed density was minimized at the high loading setting, with the reduction in 2020 being significant. The middle weeding timing caused the least crop damage, while reducing the final weed density by approximately one-third compared with the control (without mechanical weeding), which was the most desired outcome among the three timings tested.

The investigation was carried out during 2014–2016 in the land of General Toshevo, the South Dobrudzha region of Bulgaria on slightly leached chernozem soil type. The effect of the types of soil tillage for sunflower given bellow was followed: ploughing at 24–26 cm, chisel-plough at 24–26 cm, disking with disk harrow at 10–20 cm and direct sowing (no-tillage) on the bulk density, the moisture content and the temperature of soil. The additional soil tilths of the areas subjected to ploughing, chisel-ploughing and disking with disc harrow included double spring pre-sowing cultivation with harrowing. To destroy the emerging weeds in the variant with direct sowing, a total herbicide was applied. The investigated physical parameters of soil were followed during three main stages of sunflower development: emergence, flowering and technical maturity. The bulk density of soil was determined by soil samples taken from the 0–10, 10–20 and 20–30 cm layers. The soil temperature was read at 800, 1200 and 1600 h to depth 2, 5, 10, 15, 20 and 25 cm with classical soil thermometer. For evaluation of the results dispersion and regression analyses were used. In the slightly leached chernozem soil type, the conventional ploughing leads to lower bulk density in the cultivated soil profile. Under minimal tillage, slight increase of bulk density of the layer underlying the cultivated one was observed over time. The bulk density under tillage without turning of the soil layer and no-tillage was changed and formed primarily under the influence of physical and climatic factors, and under minimal tillage – under the cultivated layer. Under all investigated types of soil tillage, bulk density increased down the soil profile. Replacing ploughing with tillage without turning of the soil layer, minimal and no-tillage lead to decrease of soil temperature. The most significant differences were observed in the 0–10 layer, which, on its part, conditioned accumulation and transfer of thermal energy along the soil profile. The soil temperature decreased with the reduction of the number and depth of the soil tillage operations. The temperature amplitudes between the surface layer and the underlying soil horizons in the areas with ploughing, chisel ploughing minimal and no-tillage were lower. The results concerning the values of the investigated physical properties of soil under different types of soil tillage were statistically significant at different levels of P.

Made available in DSpace on 2020-12-12T02:47:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Sugarcane production system requires intense agricultural mechanization to prepare the soil and there are enormous questions about which soil preparation should be adopted in order to improve field productivity. Thus, this work aimed to verify the energy optimization in sugarcane soil preparation for increasing productivity. The experiment was carried out with a banded experimental design, with six replications, consisting of two soil tillage systems, one system used was conventional tillage and the other, deep preparation in band. Conventional tillage was carried out with a heavy harrow and subsoiler, while deep preparation was performed in band with “penta” equipment. In both soil tillage systems, the planting was carried out mechanically. Variables were measured: hourly fuel consumption (L h−1), area fuel consumption (L ha−1), operational yield (h ha−1), biometric parameters and crop productivity. The highest hourly fuel consumption occurred in conventional tillage. The different soil tillage systems did not influence mechanized planting. The highest productivity was obtained in the deep band preparation. Agronomy Department Cassilândia University Unit Mato Grosso do Sul State University—UEMS, 306 Road, Km 6 Crop Production and Breeding Department College of Agricultural Sciences UNESP—São Paulo State University, Av. Universitária, 3780 Rural Engineering and Agricultural Mechanization Department College of Agricultural Sciences UNESP—São Paulo State University, Av. Universitária, 3780 Crop Production and Breeding Department College of Agricultural Sciences UNESP—São Paulo State University, Av. Universitária, 3780 Rural Engineering and Agricultural Mechanization Department College of Agricultural Sciences UNESP—São Paulo State University, Av. Universitária, 3780

Before any late-season weed control operations are planned to manage herbicide-resistant weeds, it is essential to evaluate the plants’ maturity and shattering potential. Our goal was to assess the seed-shattering phenology of common ragweed (Ambrosia artemisiifolia L.) using pollination bags as seed traps. A secondary goal was to evaluate the efficiency of these traps. Trials were conducted from 2014 to 2017 at two locations in eastern Canada (Saint-Jean-sur-Richelieu, QC, and Harrow, ON). At each location, three adjacent fields were seeded with spring wheat (Triticum aestivum L.), soybean [Glycine max (L.) Merr.], or corn (Zea mays L.). Each field was divided into four replicate blocks that included two treatment plots with 5 weeds m−2 planted on the same date as the crop or when crop plants had two leaves (early or late emergence). To evaluate shattering in time, the experiment included up to 12 weekly collection dates (subplots). In each subplot, weeds were individually bagged at flowering (using mesh bags) until collection, when the number and viability of shattered and retained seeds per plant was recorded. Weather data as well as crop and weed stages were recorded. The effect of the pollen bags on seed retrieval and viability was evaluated by installing open and closed bags in corn and uncropped (bare) plots at a single location. Ambrosia artemisiifolia seed biomass was equivalent or higher in closed bags, and seed viability was equivalent or slightly reduced. No seeds were produced before harvest in spring wheat, as dispersal started in September. The percentage of seeds retained on the plant decreased linearly (1 site-year) or followed a logistic equation (4 site-years) with day of year or growing degree days. Dispersal in time was similar between early- and late-emerging weeds and similar in both corn and soybean. On average, more than 50% of A. artemisiifolia seeds were dispersed before harvest in corn and soybean.

The use of agroforestry systems (AFS) for the recovery of degraded lands allows the diversification of biomass production and can increase the ecological, economic and social resilience of the restored areas. We evaluated a degraded soil 5 years after the establishment of three AFS with different managements using the carbon stored in the soil and tree biomass as quality indicators. In the AFS we used 33 species. Thirty were native trees interspersed with three cropped species: Hevea brasiliensis, Malpighia glabra L. and Bixa orellana. The AFS treatments were: AFS1 (Mower, trees planted in hollows, spacing 3 m × 2 m, 300 g hollow−1 of limestone + 36 g hollow−1 of P2O5, no plantation between rows); AFS2 (Herbicide, trees in hollows, 3.5 × 2 m, maize (Zea mays) between lines, 2 Mg ha−1 of limestone + 2 Mg ha−1 of filter cake + 300 kg ha−1 of NPK 8-28-16); AFS3 (Plough, harrow, scarifier, trees in furrows, 3.5 × 2 m, maize between lines, fertilization similar to the AFS2). As reference, we used a soil under a forest fragment nearby the main experiment. In 5 years, there was an increase of 10 Mg ha−1 of the soil C stocks under the AFS, which represents an average accumulation rate of 2 Mg ha−1 year−1. The carbon stocks in the biomass in AFS were lower than in the forest. The different management practices used in the implementation of the AFS do not directly affect the total carbon stocks in the 0–100 cm soil layer.

Crop yields usually respond to crop rotation, but they may interact with tillage system and year (as an integration of variables, mainly in terms of temperature and precipitation). The objective of this study was to evaluate the determinants of the irrigated durum wheat yield under long-term tillage system × crop rotation (2000–2008). Tillage factor considered two levels: moldboard plow plus disk harrow (CT) and no-till (NT) and crop rotations factor had three levels: wheat–fallow–canola (W–F–C), wheat–maize (W–M) and wheat–fallow (W–F). Last year, we evaluate a maize crop as a physical soil quality indicator. The tillage system × crop rotation interaction was not significant, and the lowest durum wheat yield and biomass were observed in the W–M rotation experimental year (reduction of 18.7%). Tillage system × year interaction was significant for wheat yield. Partial least squares analysis indicated that precipitation was high between sowing and 3rd leaf was determinant for yield, and a negative correlation between these variables was observed. Despite the above, no differences were observed in the maize yield directly attributable to physical soil properties. Our study shows that rainfall distribution appears to cause of the tillage system × year interaction for durum wheat yield. When the precipitation was higher (160 mm) between sowing and 3rd leaf, yield decreased in NT by 37% compared to CT possible due to a hypoxia condition and/or low plant-available soil nitrogen, with a negative effect over tillering, affecting in the long-term spike number per square meter.

The widespread use of herbicides in cropping systems has led to the evolution of resistance in major weeds. The resultant loss of herbicide efficacy is compounded by a lack of new herbicide sites of action, driving demand for alternative weed control technologies. While there are many alternative methods for control, identifying the most appropriate method to pursue for commercial development has been hampered by the inability to compare techniques in a fair and equitable manner. Given that all currently available and alternative weed control methods share an intrinsic energy consumption, the aim of this review was to compare methods based on energy consumption. Energy consumption was compared for chemical, mechanical, and thermal weed control technologies when applied as broadcast (whole-field) and site-specific treatments. Tillage systems, such as flex-tine harrow (4.2 to 5.5 MJ ha−1), sweep cultivator (13 to 14 MJ ha−1), and rotary hoe (12 to 17 MJ ha−1) consumed the least energy of broadcast weed control treatments. Thermal-based approaches, including flaming (1,008 to 4,334 MJ ha−1) and infrared (2,000 to 3,887 MJ ha−1), are more appropriate for use in conservation cropping systems; however, their energy requirements are 100- to 1,000-fold greater than those of tillage treatments. The site-specific application of weed control treatments to control 2-leaf-stage broadleaf weeds at a density of 5 plants m−2 reduced energy consumption of herbicidal, thermal, and mechanical treatments by 97%, 99%, and 97%, respectively. Significantly, this site-specific approach resulted in similar energy requirements for current and alternative technologies (e.g., electrocution [15 to 19 MJ ha−1], laser pyrolysis [15 to 249 MJ ha−1], hoeing [17 MJ ha−1], and herbicides [15 MJ ha−1]). Using similar energy sources, a standardized energy comparison provides an opportunity for estimation of weed control costs, suggesting site-specific weed management is critical in the economically realistic implementation of alternative technologies.

Mechanical weed control in low competitive, organic vegetable production systems is challenging, particularly in fields with large populations of Galinsoga spp. (Asteraceae). Various false seedbed techniques are used prior to crop planting or sowing to prevent weed emergence, albeit with variable success. This study investigated the impact of machinery type (flamer, hoe and harrow), number of passes (2 and 4), tillage depth (1-4 cm) and intensity (double and single hoeing, and hoeing with or without additional harrowing) on weed emergence and seedbank density in 0-5 cm topsoil of organic vegetable fields. False seedbed machinery that did not or minimally disturb the soil was most appropriate for preventive control of Galinsoga quadriradiata (Hairy galinsoga) and total weed seeds, with reductions in seedling emergence up to 99% and 73%, respectively, for flaming, and 74% and 67%, respectively, for 1 cm deep hoeing, 1 month after false seedbed creation. Compared with 1 cm deep hoeing, 1 cm deep harrowing was 16% less effective in the control of emerged seedlings, while flaming was highly effective in preventing weed seedling emergence, even after a low number of passes. Tillage intensity was less important than tillage depth for the reduction in weed emergence and seedbank density. Overall, tillage was more effective for seedbank reduction than flaming.

Made available in DSpace on 2019-10-06T16:03:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-03-01 Alongside the agricultural development in Brazil, concerns have arisen about its environmental impacts, such as the emissions of CO2 resulting from soil cultivation and management practices in agricultural production systems. The aim of this study was to investigate the temporal variation in CO2 emissions and soil physical attributes in response to the process of soil particle rearrangement after soil tillage operations. The study was conducted in three adjacent areas of 10 × 3 m, subjected to two soil tillage systems: (i) rotary hoe + conventional leveling harrow, representing an intensive soil tillage (IT); (ii) disc harrow + leveling harrow, characterizing a reduced tillage (RT). The soil of the third area was not tilled, representing the no-tillage (NT) system. Daily measurements of soil CO2 emission (FCO2), soil temperature, soil moisture, pore class distribution, bulk density, penetration resistance, water-free pore space, weighted mean diameter, aggregate stability index, total organic carbon, and particulate organic carbon were performed during a period of 29 days after soil tillage. On the first day after tillage, FCO2 was 87% higher in the plot under IT (3.86 μmol m−2 s−1) than RT (2.06 μmol m−2 s−1) and 147% higher than in the plot under NT (1.56 μmol m−2 s−1). The variations in soil density and penetration resistance declined as of the 12th day after tillage. This effect was considered a natural process of soil consolidation and influenced the temporal variation of soil CO2 emissions. Pore class distribution is an essential physical attribute to explain the temporal variations of soil CO2 emissions, and these classes are influenced by the applied management. Therefore, the study of these attributes must be taken into account when assessing the variation of CO2 emissions from agricultural soils. Department of Exact Science School of Agricultural and Veterinary Sciences São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane s/n Department of Biomass Brazilian Bioethanol Science and Technology Laboratory (CTBE), Rua Giuseppe Máximo Scolfaro, 10000 Marília University (UNIMAR) Campus Universitário, Av. Higino Muzi Filho, 1001, Jardim Araxa Department of Soils and Fertilizers School of Agricultural and Veterinary Sciences São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane s/n Department of Exact Science School of Agricultural and Veterinary Sciences São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane s/n Department of Soils and Fertilizers School of Agricultural and Veterinary Sciences São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane s/n

Tall weeds escaping early weed management, such as weeds resistant to one or multiple herbicides, are an increasing concern. When weeds reach a certain size, few options other than hand weeding will limit the production and dispersal of seeds. The objective of this project was to evaluate the efficacy of the Bourquin Organic Weed Puller® (a rotating series of wheels that grab and pull) at removing tall weeds before they shed seeds in soybean and adzuki bean. Trials were set up in Canada at the Agriculture and Agri-Food Canada research farms at Saint-Jean-sur-Richelieu (SJR), QC (2 yr), and Harrow (HAR), ON (1 yr), on a loamy and a sandy soil, respectively. The experimental design included crops of different potential heights (different soybean cultivars and adzuki bean), two weed species per location (common lambsquarters [both locations] and common ragweed or redroot pigweed at HAR), and two pulling dates. The set-up also included weedy and herbicide-treated control plots. Weeds overtopping the crop canopy by at least 10 cm were tagged and characterized. Damage from the weed puller was rated as 1, pulled (desired effect); 2, cut; 3, folded; 4, stripped; and 5, intact. The seed production of damaged and intact weeds was also recorded. Less than one-third of common ragweed or redroot pigweed plants were pulled during any treatment combination. The highest pulling rates were observed for common lambsquarters at SJR (43%), but very few were pulled at HAR (3.1% max). Pulling rates were not high enough to potentially control seed inputs from herbicide-resistant populations, and successfully pulled common lambsquarters left on the ground produced thousands of viable seeds.Nomenclature: Common lambsquarters, Chenopodium album L. CHEAL; common ragweed, Ambrosia artemisiifolia L. AMBEL; redroot pigweed, Amaranthus retroflexus L. AMARE; adzuki bean, Vigna angularis (Willd.) Ohwi & Ohashi; soybean, Glycine max (L.) Merr

Harrowing is mostly applied with a constant intensity across the whole field. Heterogeneous field conditions such as variable soil texture, different crop growth stages, variations of the weed infestation level, and weed species composition are usually not considered during the treatment. This study offers a new approach to sensor-based harrowing which addresses these field variations. Smart harrowing requires the continuous adaptation of the treatment intensity to maintain the same level of crop selectivity while ensuring a high weed control efficacy. Therefore, a harrow was equipped with a sensor-system to automatically adjust the angle of the harrow tines based on a newly developed decision algorithm. In 2020, three field experiments were conducted in winter wheat and spring oats to investigate the response of the weed control efficacy and the crop to different harrowing intensities, in Southwest Germany. In all experiments, six levels of crop soil cover (CSC) were tested. The CSC determines the balance between crop damage and weed removal. Each experiment contained an untreated control and an herbicide treatment as a comparison to the harrowing treatments. The results showed an increase in the weed control efficacy (WCE) with an increasing CSC threshold. Difficult-to-control weed species such as Cirsium arvense L. and Galium aparine L. were best controlled with a CSC threshold of 70%. However, 70% CSC caused up to 50% crop biomass loss and up to 2 t&middot, ha&minus, 1 of grain yield reduction. With a CSC threshold of 20% it was possible to control up to 98% of Thlaspi arvense L. The highest crop biomass, grain yield, and selectivity were achieved with an CSC threshold of 20&ndash, 25% at all locations. With this harrowing intensity, grain yields were higher than in the herbicide plots and a WCE of 68&ndash, 98% was achieved. Due to the rapid adjustment of tine angle, the new sensor-based harrow allows users to apply the most selective harrowing intensity in every location of the field. Therefore, it can achieve equal weed control efficacies as using herbicide applications.

Preferred alternatives of residue management leave some part of residue on the soil surface and incorporate the remaining part of it into the soil. The ability of some passive tillage implements is not acceptable for residue management. A power harrow which is commonly used in Turkey for reduced tillage, with two different ground driven types of rollers and various operating conditions was used to determine its effect on the distribution of wheat residue cover on the soil surface, the amount of incorporated residue into the soil, soil physical properties and fuel consumption. The experiment was designed with two different blade peripheral speeds (3.09 and 3.44 m s−1), three tractor forward speeds (0.58, 0.92 and 1.26 m s−1) and two different types of ground driven rollers (heavy and light type) as treatments and with three replications. According to the obtained results tractor forward speeds affected fuel consumption, the residue cover and residue incorporation values. Generally, a negative relationship was determined between tractor forward speeds, fuel consumption and residue incorporation. Increasing the blade peripheral speed increased fuel consumption and the residue incorporation rate. However, there was a negative relationship between the blade peripheral speed and the residue cover (p

Since tillage is one of the processes requiring high power, energy consumption in field operations is of great concern to farmers and researchers. A combined tillage tool has been recognized as one measure to reduce the power requirements in field preparation. In this research work, a combined tillage tool consisting of a subsoiler and rotary harrow (joined using four different linkage configurations) were tested under actual field conditions. The test parameters consisted of: tillage tools (combined tillage tool with four different linkages, a sole subsoiler and a sole rotary harrow), forward speeds (1.79, 2.67, and 3.33 km h−1), and rotational speeds of the rotor (299 and 526 rpm). The experiment site was located at 14.00 °S and 99.58 °E having a clay soil type and bulk density in the range 1.5–1.7 g cm-3 with an average water content of 16.6% (db). The results indicated that the combined tillage tool was able to reduce the draft for subsoiling by 4.4–11.3% depending on the linkage configuration compared with the same sole subsoiler used alone. There were significant effects of the rotational speed of the rotary harrow and the forward speed on the drawbar power, the PTO power, and the total power. The combined tillage tool with linkage IV consumed the least total power. The combined tillage tool with linkages I to IV used less total power by 13.7, 12.2, 10.5, and 15.3%, respectively, compared with the combined power required by the sole subsoiler and sole rotary harrow working separately.

A field experiment was conducted at ICAR-Indian Institute of Sugarcane Research, Lucknow, with three tillage practices (T1: Control- two times ploughing with harrow and cultivator, each followed by...

Weed control is one of the most important practices for a satisfying crop performance. In organic farming, weeds are mainly controlled by using mechanical methods, which may result in incomplete crop selectivity. Maize is one of the crops for which mechanical weed control is commonly applied. To assess weed control efficacy and the possible crop injuries caused by mechanical interventions (harrowing, hoeing and ridging), a field experiment was carried out in 2013–2014 on traditional flint Italian varieties of maize (Marano, Ottofile, Pignoletto, Nostrano and the hybrid Maranello) suited for organic food production. The study included the following treatments: weed control with a spring tine harrow + hoeing and ridging (STH), manual weed removal all season long (MWR), spring tine harrowing + manual weed removal (STH + MWR) and an untreated check (CHK). In the 2 years, the experiment was carried out in two similar fields in which 60 plots (6 × 10 m) were arranged in a RCBD with three replications. Weed control efficacy was assessed by determining weed density, weed species composition and weed cover after each mechanical intervention in the STH and CHK plots. Weed diversity indices were also calculated at the final assessment. The possible crop injuries caused by mechanical means were assessed by determining maize plant height, number of leaves, and plant density after each mechanical intervention. At maturity, maize yield and other yield-related traits (1000-seed weight, hectolitre weight, and grain moisture) were determined. The results showed that the mechanical treatments lowered the weed infestation, without changing weed species dominance and slightly lowering species richness; even though they were not able to completely control the weeds. In both years, the final weed density in STH plots was of about 50 plants m−2. Better weed control was obtained when weeds were at early growth stages and with a repeated number of harrowing. Mechanical weeding did not cause significant injury in terms of plant height nor density; however, for Marano and Maranello, a delay in the crop cycle was observed as shown by the lower number of leaves in STH compared with MWR. Yield ranged from 0.3 t ha−1 for Marano CHK to 10.4 t ha−1 for the hybrid Maranello in MWR + STH. Yield and yield-related traits were not affected by mechanical weeding.

Crop management approaches, specifically tillage and planting patterns, influence crop productivity in the arid and semi-arid areas. A field experiment was carried out to assess the influence of crop establishment methods under different tillage systems on seed cotton (Gossypium hirsutum L.) yield (SCY), irrigation water productivity (IWP), and yield attributes of irrigated cotton under the ecological conditions of the south of Iran during 2017 and 2018. The experimental design was a randomized complete block with split-plot arrangement in three replicates. The planting patterns were cotton transplanting using a semi-automatic transplanter (CTr), and a cotton direct seeding (CDs) as the main plots. The subplots consisted of four tillage systems: chisel plow plus one disk harrow pass (Til.1), chisel plow plus one power harrow pass (Til.2), stubble cultivator plus one disk harrow pass (Til.3), and moldboard plow plus two disk harrow pass (Til.4). On a two-year average, CTr led to a significant reduction (15.4 %) in the amount of applied water for irrigation as compared to CDs. Cotton grown in CTr produced significantly more total number of bolls and larger boll size compared to those grown by the direct-seeded method in both years (46.7 and 8.5 %, respectively). The maximum seed cotton yield (SCY) and irrigation water productivity (IWP) were observed from the CTr × Til.1 and CTr × Til.3, whereas the minimum yield and irrigation water productivity occurred in the CDs × Til.4 in average of two years. Results of this study suggested that application of CTr in combination with Til.1 could give an optimum seed cotton yield and water productivity compared to individual use of conservation tillage (Til.1 and Til.3) in cotton-cultivated regions of the southern part of Iran and other areas with the similar ecological conditions.

Public awareness and environmental policies have increased interest in applying non-herbicide weed control methods in conventional farming systems. Even though mechanical weed control has been used for centuries in agricultural practice, continuous developments—both in terms of implements and automation technologies—are continuously improving the potential outcomes. Current mechanical weed control methods were evaluated for their weed control efficacy and effects on yield potential against their equivalent herbicide methods. Furthermore, not much is known about the correlation between weed control efficacy (WCE) of different mechanical methods at varying weed density levels. A total of six experiments in winter wheat (2), peas (2), and soybean (2) were carried out in the years 2018, 2019, and 2020 in southwestern Germany. Harrowing and hoeing treatments at different speeds were carried out and compared to the herbicide treatments and untreated control plots. Regarding the average WCE, the combination of harrowing and hoeing was both the strongest (82%) and the most stable (74–100%) mechanical treatment in the different weed density levels. Whereas, in average, hoeing (72%) and harrowing (71%) were on the same WCE level, but harrowing (49–82%) was more stable than hoeing (40–99%). The grain yields in winter wheat varied between 4.1 Mg∙ha−1 (control) and 6.3 Mg∙ha−1 (harrow), in pea between 2.8 Mg∙ha−1 (hoe slow) and 5.7 Mg∙ha−1 (hoe fast) and in soybean between 1.7 Mg∙ha−1 (control) and 4 Mg∙ha−1 (herbicide). However, there were no significant differences in most cases. The results have shown that it is not possible to pinpoint a specific type of treatment as the most appropriate method for this cultivation, across all of the different circumstances. Different field and weather conditions can heavily affect and impact the expected outcome, giving, each time, an advantage for a specific type of treatment.

Alopecurus myosuroides Huds. (blackgrass) frequently occurs in Western European cropping systems. It causes high yield losses in winter-cereals and winter-oil-seed rape. Several preventive measures to control blackgrass are available, however long-term studies with combinations of preventive and direct control methods are rare. In this seven-year study at two locations in Germany, three crop rotations with different proportions of winter-annual crops, four herbicide strategies and four tillage measures were combined and their interactions were analyzed. Aim was to investigate the effects on blackgrass densities, crop yields and contribution margins. Densities increased from 14 to 3098 heads m-2 and 201 to 3563 heads m-2 in the rotation containing only winter-annual crops without weed control and reduced tillage. Rotations with spring crops reduced densities by up to 98%. Inversion tillage with a moldboard plough and false seedbed preparation using a harrow (shallow) and a rotary harrow (deep) reduced blackgrass infestations by up to 70% compared to solely reduced conservation tillage with a chisel plough. Blackgrass densities were 23–99% (average 59%) lower, when herbicide Mode of Action (MOA) was rotated in every year compared to herbicide strategy continuously using the same MOA. Grain yield loss in the control plots due to blackgrass competition amounted up to 3.0 t ha-1 (41%). Contribution margins were highest in the cropping systems that combine crop rotation, inversion tillage, false seedbed preparation and herbicide MOA rotation. The results highlight the benefits of integrated weed management in regard to weed control and economic sustainability.

This study quantifies, using the Life Cycle Assessment (LCA) method, the environmental impact of sequences of operations for seedbed preparation for arable crops under different soil textures and soil refinement intensities. Comparing the environmental loads of alternative sequences of operations permitted to detect the most environmentally sustainable sequence in each working condition. To this purpose, 13 alternative sequences of field operations for seedbed preparation were analysed, considering primary and secondary soil tillage and minimum tillage. The study was carried out considering a cradle to farm gate perspective and selecting as functional unit “1 ha tilled with an appropriate soil refinement for sowing and seed germination”. Three 60-ha farms in Northern Italy were considered. Inventory data (e.g., farm and field information, machinery fleets, fuel, lubricant and materials consumptions and exhaust gases emissions) were calculated with the model ENVIAM (ENVironmental Inventory of Agricultural Machinery operations). The impact assessment was completed with the ReCiPe characterisation method. Results showed that seedbed preparation completed with two implements (one for primary and one for secondary soil tillage) instead of three (e.g., one for primary and two for secondary soil tillage) results in a better environmental performance on impact categories (e.g., eutrophication, ecotoxicity and metals depletion) affected by the manufacturing phases and by the consumption of materials along machinery life span. The impact categories affected by fuel consumption and exhaust gases emissions showed the best results with low energy-consumptive operations (e.g., slatted plough, no-Power Take Off harrow and minimum tillage). Coarse textured soils and soils lowly refined (i.e. unrefined soil particles adapt for crops characterized by seeds with a size close to that of winter crops or by high seed density) showed low burdens on all impact categories, whereas fine textured and highly refined soils (i.e. small soil particles adapt for crops with small seeds or by low seed density) were responsible for the highest impacts. This is primarily due to the larger number of harrowing repetitions and of energy and fossil fuel consumption. The results can be up-scaled to arable crop production systems with similar pedo-climatic and operative features, such as other Mediterranean countries. Farmers associations, stakeholders and politicians could promote policies and define incentives that encourage producers to adapt to more environmentally sustainable crop productions.

SUMMARYCropping systems in the lowlands of temperate South America have been based on irrigated rice and beef-cattle production. Plough-and-harrow is still the most used method to prepare the soil after a season of irrigated rice, but it causes high soil disturbance and is time- and energy-demanding. To improve the sustainability of a rice–soybean rotation system, we studied an alternative method for soil preparation based on a heavy knife-roller. This method was evaluated during three cropping seasons and compared to the plough-and-harrow, applied after the harvest of irrigated rice in a flat hydromorphic soil in south Brazil. In the subsequent summer, soybean was seeded using a no-tillage seeder. Observations on soybean establishment and grain yield demonstrated that the alternative method performed as well as the plough-based system. Benefits of the roller-based method were a 50% reduction in energy consumption for soil preparation, corresponding to a 22% increase in overall energy use-efficiency of soybean production. Labour time and greenhouse gas emissions for soil preparation were reduced with 29 and 55%, respectively. Next to these savings, the roller-based method can also be performed shortly after rice harvest, creating better opportunities for cover crops or pastures in between rice and soybean. In conclusion, the equivalent agronomic and superior sustainability performance makes the knife-roller method an appealing alternative for seedbed preparation after irrigated rice in lowland production systems.

The processes of soil redistribution caused by hoeing tillage in hilly areas have been increasingly recognized for nearly two decades. Yet, few studies have examined the effects of hoeing tillage on soil redistribution in rocky mountainous areas. Due to a high rock fragments content of gravelly soils, a special type of hoe called the two-tooth harrow has been widely used in the Yunnan-Guizhou Plateau, China. In order to assess gravelly soil redistribution, a series of tillage experiments were set up and the subsequent data were compared with those acquired previously in hilly areas. The displacement distance of gravelly soils increased with slope gradient linearly in the range of 0.05 to 0.69 m m−1; however, when the slope gradient extended further, an exponential equation could better describe the relationship between them. The repose angle of gravelly soils was approximately 0.69–0.70 m m−1. Large-size rock contents and implement types are two important factors affecting tillage depth. Tillage transport coefficients (k3 and k4) of gravelly soil in rocky mountainous areas were 40 and 78 kg m−1 tillage pass−1, respectively, displaying a slightly large k3 value but a significantly small k4 value compared with those in hilly areas. Due to its energy saving and applicability to gravelly soils, the two-tooth harrow is more attractive to farmers than the normal hoe in rocky mountainous areas. Moreover, the two-tooth harrow is proved to be efficient and effective in reducing tillage erosion than the normal hoe.

Energy used for tillage is an input with a high impact on the cost of crop production, it is desirable to till the soil using minimum energy. The objective of this study was to compare the specific energy expenditure, effect on soil bulk density, and forage yield of maize, by three tillage systems: Disk plow/Disk Harrow/planter (DDP), Chisel plow/Disk harrow/planter (CHDP) and No-Tillage (NT). Energy was measured for tillage operations in the summer season of 2013, 2016, and 2017. Bulk density in 2013 and 2016. Yield in 2013 and 2014. The variables of drawbar force (kN), working speed (m s&minus, 1), width (m), depth (m), fuel consumption (L ha&minus, 1), bulk density (g cm&minus, 3), and dry matter yield (Mg ha&minus, 1) were measured. Results showed that there were significant differences in the amount of energy used per ha, DDP used an average of 379.75 MJ, CHDP 135.01 MJ, and NT 26.43 MJ. The average energy applied to the soil mass for each system was 400 J kg&minus, 1 for DDP, 255.13 J kg&minus, 1 for CHDP, and for NT was 237.8 J kg&minus, 1. The overall energy efficiency was, 18.23% for DDP, 6.88% for CHDP, and 4.77% for N. The bulk density decreased significantly after three years for NT. There were no significant differences in dry matter yield. In the semiarid condition of Mexico, CHDP and NT are options for saving from 64% to 93% of energy, compared with DDP.

Harrowing is one of the most popular mechanical methods to control weeds. Nevertheless, the relationship between the effect of different harrowing intensities using spike-tooth harrow in barley-pea intercrop on the yield and mycoflora of grains has not yet been studied. Therefore, the aim of this study was to assess the effect of harrow intensity using spike-tooth harrow in barley-pea mixture on the mycological quality of harvested grains, grain yield, as well as influence of barley and pea grain moisture on the abundance of fungi. The field experiment was carried out during 2010&ndash, 2012, and it was conducted using a randomized complete block design with four replicates. Weed control was mechanical and chemical. In this study, we have shown that harrowing in barley-pea intercrops does not reduce the yield of either mixture components, both with respect to grain quantity or mycological quality after harvest, compared to controls&mdash, without harrowing and the herbicide MCPA (2-methyl-4-chlorophenoxyacetic acid). However, increasing the intensity of harrowing did not result in a consistently larger crop yield or reduction in fungal abundance in the grains. The grains&rsquo, internal structures and surface of both tested components of the mixture were colonized to a large extent by cosmopolitan fungi, of which Alternaria alternata (Fr.) Keissl. was the most abundant.

The presence of straw hinders the sowing of soybean cultivated in succession to rice, in areas irrigated by flooding. This study aimed to evaluate the combination of different configurations of a rice harvester and subsequent activities in the operational and energetic demand of rice straw management and in the soil surface roughness, in order to cultivate soybean in succession. Three independent experiments were conducted in a completely randomized design, as well as evaluated the fuel consumption, effective operating speed, working capacity and final surface roughness of the ground. The energy costs of harvesting rice do not increase when the automated harvester operates with a spreader to distribute the straw on the ground and to avoid the formation of furrows. The presence of rice plant residues in the field increases the skidding of the tractor when pulling the knife-roller, with a consequent reduction of the operating speed, but this does not affect the operational capacity and the fuel consumption. The increase in the number of light harrowings, from one to two operations, in areas worked with knife-roller or intermediate harrow, requires more time and fuel in the management of the soil and rice straw, but leaves the ground with less surface roughness. The management system with knife-roller operation and two light harrowings is the most appropriate method to prepare the soil for soybean cultivation after rice, because it provides the best combination of technical and energetic performance.

Harrowing is a process that reduces the size of soil clods and prepares the field for seeding. Rotary harrows are a common piece of equipment in North Italy that consists of teeth rotating around a vertical axis with a processing depth of 5–15 cm. In this study, the topsoil movement in terms of distance and direction were estimated at different rotary harrow working conditions. A total of eight tests was performed using two forward speeds of 1 and 3 km/h, two working depths of 6 and 10 cm and two levelling bar positions of 0 and 10 cm from the ground. In order to simulate and follow topsoil movement, Radio-Frequency Identification (RFID) tags were inserted into cork stoppers and distributed in a regular pattern over the soil. Tags were distributed in six lines along the working width and repeated in three rows for each test: a total number of 144 tags was tracked. Results showed that there were no significant differences between the performed tests, on the other hand the reported tests highlight the effectiveness of the RFID monitoring approach.

Farm machinery selection, operation and management directly impact crop cultivation processes and outputs. A priori quantification of technical and financial needs allows definition of proportionate distribution and management of available resources and simplification of selection process. Appropriate planning, association and adjustment of the power unit and implement are required for soil cultivation. Consideration of functional parameters of the implement, their proper estimation and operation directly impact the soil structure, productivity and return on investment. Thus, a modelling approach was implemented for the definition of possible parameter-price relations for tillage equipment. The performed analysis allowed us to investigate the main relevant parameters, quantify their impact, and elaborate forecasting models for price, power, mass and working width. The significant relevance of the technical parameters and adjustment issues were outlined for each tillage implement group. For harrows and cultivators, the dependencies between studied parameters expressed better predictive qualities, especially for price-mass relation (R² &gt, 0.8). While for ploughs power and mass relation had a primary output (R² = 0.7). The prediction features of the models provided reliable results for the estimation of the indicative values of the price and parameters of the implements.

Subsoil compaction at 15–30 cm depths due to the increase of bulk density or decrease in porosity after long-term no tillage or reduced tillage (e.g. rotary tillage or harrow tillage) is of growing concern. Deep tillage is generally regarded as an important method to reduce subsoil compaction due to long-term conservation tillage and thereby improve crop production and soil conditions. We compared the responses of crop yield and soil carbon (C) among 10-year no tillage (NT), rotary tillage (RT), and harrow tillage (HT) treatments, and their conversions to deep tillage (DT) for 4 years involving NT-DT, RT-DT and HT-DT treatments. The soil organic carbon (SOC) pool under the NT treatment was 29 and 91% higher than the SOC pools of the HT and RT treatments, respectively, whereas the NT annual yield decreased by 0.6 Mg ha −1 yr −1 over 10 years. The NT-DT, RT-DT and HT-DT treatments increased crop yield by 35, 24 and 24% and altered the SOC pool by −1.5, 15.6 and 13.2 Mg ha −1 over the 4 years of deep tillage compared with the corresponding values for NT, RT, and HT, respectively. Therefore, conversion to DT after long-term NT, RT, and HT use can benefit crop yield and play an important role in improving soil carbon sequestration following the long-term adoption of RT and HT systems in North China.

Soils are one of the most biologically diverse habitats within the terrestrial ecosystem. Although soils are vital to the provision of important ecosystem services, their direct protection and sustainable management are often lacking within conservation policy. Many grassland soils have undergone considerable management intensification and are subject to degradation pressures. Soil compaction is an important form of soil degradation that can reduce soil productivity and crop yields, although the impacts can be reversed through natural processes and mitigated through management interventions. While commonly used, substantial knowledge gaps exist regarding the impact of soil compaction mitigation techniques on key soil macrofauna; many of these organisms are essential to soil function. A complete split-plot design was used to investigate the impacts of mechanical loosening (subsurface soil disturbance using tines or radial blades without significant soil mixing or inversion) and power harrow cultivation (shearing and mixing of soil to prepare a seedbed for the establishment of a deep-rooting forb and legume mix) on the abundance and biomass of earthworms up to two years post-treatment. Mechanical loosening was undertaken at two depths, c. 20 cm and c. 35 cm as two separate treatments. There was a negative effect of mechanical loosening at both depths on the abundance and biomass of anecic earthworms, lasting up to two years post-treatment. There was no significant effect of power harrow cultivation on the abundance or biomass of earthworms. These negative effects are consistent with other studies that have shown mechanical loosening to be a source of earthworm mortality. Although these findings resulted from a single episode of power harrow cultivation and mechanical loosening at a single site, the results indicate that the mechanical loosening of grassland soil can have a negative impact on important soil macrofauna and should possibly only be undertaken when the soil is in the most severely degraded conditions. Further work is needed to determine whether the negative impact of mechanical loosening is common to multiple sites and soil types and to link the reduction in earthworm number and biomass to future soil function.

A field experiment during 2010–2014 was conducted at Indian institute of Sugarcane Research, Lucknow, with three tillage practices (T1: control—two times ploughing through harrow and cultivator, each followed by planking before sugarcane planting, T2: deep tillage through disc plough (depth 25–30 cm) before planting followed by harrowing, cultivator and planking and T3: subsoiling at 45–50 cm, and deep tillage through disc plough/mouldboard plough (depth 25–30 cm) followed by harrowing, cultivator and planking before planting), two soil moisture regimes (M1: 0.5 IW/CPE ratio and M2: 0.75 IW/CPE ratio) at 7.5 cm depth of irrigation water, and four N levels (N1-0; N2-75; N3-150; N4-225 kg N/ha) in sugarcane crop. The higher mean SMBN (16.61 mg NH4–N/m2/day) during sugarcane ratoon crop was analysed as compared to plant crop (12.97 mg NH4–N/m2/day). Suboptimal moisture regime (0.5 IW/CPE) in plant crop reduced SMBN at all the stages of growth as compared to optimum moisture regime (0.75 IW/CPE). Mean SMBN at 0.5 IW/CPE was observed as 16.22 mg NH4–N/m2/day vis-a-vis 17.00 mg NH4–N/m2/day at 0.75 IW/CPE. The increasing levels of N up to 225 kg/ha increased SMBN at all the stages in both the soil depths, i.e. 0–15 and 15–30 cm (17.60 mg NH4–N/m2/day at 225 kg N/ha over 15.56 mg NH4–N/m2/day at N0). Deep tillage and subsoiling (T3) at 0.75 IW/CPE ratio and 225 kg N/ha showed the highest mean soil respiration (158 mg CO2–C/m2/day). In sugarcane plant crop, at the highest N application (225 kg N/ha), M1 (0.50 IW/CPE) showed the lowest available N, i.e. 160 kg N/ha vis-a-vis 186.00 kg/ha at 0.75 IW/CPE (M2) with conventional tillage (T1). Deep tillage increased production of millable canes which could be increased to 100,830/ha in sugarcane plant crop and 106,710/ha in ratoon crop. Mean sugarcane and sugar yields in plant crop was 68.97 and 8.28 t/ha vis-a-vis 83.67 and 10.03 t/ha in ratoon crop, respectively. Sugarcane plant crop showed 21.52 % increase in cane weight (774.75 g) due to adoption of deep tillage and subsoiling. Thus, it could be concluded that subsoiling at 45–50 cm depth followed by deep tillage at 20–25 cm depth once before planting of sugarcane with scheduling of irrigation at 0.75 IW/CPE soil moisture regime and 150 kg N/ha sustained soil microbial biomass N and in situ soil respiration besides increasing sugarcane and sugar yields in plant–ratoon system.

This study aimed to evaluate the yield and quality of winter wheat grain and soil properties in three tillage systems (TS): (1) Conventional (CT), (2) reduced (RT), and (3) no-tillage (NT). In the CT system, shallow ploughing (at a depth of 10&ndash, 12 cm from soil surface) and pre-sow ploughing (at a depth of 18&ndash, 22 cm from soil surface) were performed after the harvest of the previous crop (peas). In the RT system, the shallow ploughing was replaced by field cultivation, whereas pre-sow ploughing was by a tillage unit. In the NT system, a herbicide treatment with glyphosate (4 L ha&minus, 1) replaced the ploughing measures, whereas a tillage unit including a cultivator, a string roller, and a harrow was used before wheat sowing. Higher wheat yields were recorded in CT than in NT (by 4.3%) and in 2016 compared to 2015 (by 23.4%). The tillage system differentiated spike number m&minus, 2, whereas study years affected spike number m&minus, 2, grain weight per spike, and 1000 grain weight. Study years also influenced all quality traits of the grain, whereas tillage systems&mdash, only grain uniformity and ash content of the grain. A less uniform grain with a higher ash content was produced in NT than in CT and RT systems. Organic C content in the soil was higher in NT than in CT and RT systems. In turn, total nitrogen and phosphorus contents were higher in the soil from NT and RT than CT, whereas potassium and magnesium contents&mdash, in RT and NT compared to the CT system.

Due to a lack of accurate information regarding soil aggregate size distribution and stability, farmers in Sindh, Pakistan often apply excessive tillage, creating an overly fine seedbed that can lead to the depletion of soil organic matter (SOM) and make the soil more vulnerable to wind and water erosion. The current paper investigates the effects of conventional tillage implements on soil fragmentation and aggregate stability, along with how these factors relate to fractal dimensions. The study aims to: (i) achieve a better understanding of soil structure and establish which tillage implement provides the best soil structure and (ii) determine the function that best describes the proportion of small aggregates in the soil. Six tillage treatments were studied, including: moldboard plough + disk harrow two passes (MPDH₂), disk plough + cultivator two passes (DPC₂), cultivator two passes (C₂), cultivator four passes (C₄), cultivator six passes (C₆), and minimum tillage (disk harrow one pass) (MT) for a clay loam soil. At each of two depths (0-0.15 m and 0.16-0.30 m), four soil samples from randomly selected locations in each plot were collected (3 blocks × 6 tillage × 2 depths × 4 samples, n = 144) with the help of a soil auger. Aggregate size distribution was measured by a dry sieving method, and aggregate stability was determined by a wet sieving method. The correlations between mean weight diameter (MWD), mass fractal dimension (Dₘ), and soil aggregation were investigated. The greatest proportions of small aggregates and the lowest proportions of intermediate aggregates were found under DPC₂ followed by C₆, while a greater proportion of intermediate aggregates and a lower proportion of small aggregates was observed under MT. However large aggregates (>25 mm) were negligible across all treatments. The highest values of Dₘ were found after DPC₂, while the highest values of MWD were found after MT. The highest proportion of water stable aggregates (WSA) was found under DPC₂, while the lowest proportion was found under MPDH₂ followed by MT. Similarly, aggregate stability was greatest under DPC₂. Across all tillage implements, the highest fuel consumption was recorded under C₆ followed by MPDH₂, while the lowest occurred under MT. The Dₘ showed a negative correlation with intermediate aggregates (5.0–25.0 mm) and a positive correlation with small aggregates (

To address inhomogeneous soil properties during seedbed preparation, a system for site-specific tillage is proposed. The aim of this study was to develop a system to control the rotational speed of the power harrow based on visual detection of the soil roughness with a stereo camera. The basis for the control is the causal relationship between the measurement of soil roughness with stereo cameras, tillage intensity and the aggregate size distribution through dry sieving of the top seedbed. The stereo camera based roughness measurement system developed during this study, focused on robustness and real-time capabilities. Environmental influences on the measurement system were investigated and countermeasures were implemented. The measurement system outputs a roughness index which was the input for a control algorithm. The system was integrated into an ISOBUS Class III application which controls the PTO speed of a tractor in order to prepare a homogeneous soil roughness. During tests several seedbeds with different roughness were prepared with a power harrow following different primary tillage operations. The results of the study have been the basis for the development of a control-approach. The correlations between the aggregate size measured with sieve analysis and soil roughness measured by the stereo vision system was estimated to evaluate the system. Additionally, the comparison between soil roughness and tillage intensity showed high correlation. During validation of the controller, the homogenizing effect on the soil roughness could be shown.

Weed management in organic lentil (Lens culinaris Medik.) is challenging due to its poorly competitive nature with weeds and the lack of organic herbicides for field crops. In-crop mechanical weed control methods such as rotary hoeing, harrowing and inter-row cultivation, and the cultural practice of increased crop seeding rate, are established weed management tools in organic field crops. They have however not previously been combined into an integrated weed management system for weakly competitive grain crops. The objective of this research was to determine the effect of mechanical weed control (rotary hoeing, harrowing and inter-row cultivation) and crop seeding rate alone and in combination on weed suppression and yield in organic lentil. A two-factor randomized complete block design experiment was conducted at two locations in Saskatchewan, Canada in 2016 and 2017. The factors mechanical weed control methods including the rotary hoe, the harrow and inter-row cultivation and an untreated control, and seeding rates including conventional recommended and double recommended seeding rate. All treatments were tested as stand-alone or combined in a factorial fashion. Increased crop seeding rate and mechanical weed control affected response variables independently of each other. Doubling the seeding rate of lentil reduced weed biomass by 16% and increased lentil yield by 23% averaged across the four site-years. Treatments that included only a single mechanical weed control methods resulted in poor or incomplete weed suppression at all sites. Two mechanical weed control methods were required to maximize yield, and three were required to minimize weed biomass. Early weed control with a rotary hoe, followed by inter-row cultivation prior to canopy closure was the most consistent mechanical weed control treatment across the four site-years. Averaged across the four site-years, rotary hoeing + inter-row cultivation reduced weed biomass by 70%, and increased crop yield by 65%. The treatment maintained low weed populations across the longest time duration and controlled weeds in both the inter- and intra-row spaces, while minimizing crop injury. Doubling crop seeding rate and using two appropriately timed mechanical weed control methods provided weed suppression while increasing yield by 46% in a weakly competitive organic lentil crop.

A magnitude 9.0 earthquake and a subsequent large tsunami hit the northeastern coast of Japan on March 11, 2011. This resulted in serious damage to the reactors of the Fukushima Dai-ichi nuclear power plant (FDNPP), operated by the Tokyo Electric Power Company. Large amounts of radionuclides were released from the FDNPP, a proportion of which were deposited on the ground. In this study, we investigated soil radiocesium contamination of soybean fields in Ibaraki, approximately 170 km from the FDNPP. After the accident, we compared the radiocesium contamination in soybeans cultivated using different tillage systems and cover crop species. The different tillage systems were moldboard plow/rotary harrow (MP), rotary cultivation (RC), and no tillage (NT); the three types of winter cover crops were fallow weeds, rye, and hairy vetch; and for soybean production we used two rates of manure (0 and 1 Mg ha −1 ). MP and RC reduced the radiocesium contamination ( 134 C S + 137 C S ) in the 0–2.5 cm soil layer (509.7 Bq kg −1 for MP and 782.7 Bq kg −1 for RC), although NT left a large amount of radiocesium on the soil surface (1324.8 Bq kg −1 ). The radiocesium concentration of the rye cover crop was significantly lower than hairy vetch and fallow during 3 years. In 2013, across the tillage system, radiocesium concentration of rye was only 3.4 Bq kg −1 , although those values were 17.7 Bq kg −1 for hairy vetch and 56.4 Bq kg −1 , for fallow. The radiocesium concentration in soybean grains was significantly lower in MP and RC than in NT from 2011 to 2013. In 2013, 3 years after the FDNPP accident, the radiocesium concentration of soybean grain was 14.8 Bq kg −1 for NT, although these values were 5.8 Bq kg −1 for MP and 6.5 Bq kg −1 , for RC. The transfer factor for soybean grain was significantly lower in MP and RC than in NT, although the transfer factor in NT also decreased each sampling year from 0.12 to 0.08 after the FDNPP accident. We conclude that despite numerous benefits of the NT system for environmental conservation, soil inversion by tillage significantly decreased the radiocesium contamination of crops. Thus, tillage inversion would be appropriate to counter measures after the nuclear accident.

Although conservation tillage is widely believed to be an agricultural management practice effective for increasing soil carbon (C) accretion and associated soil quality, there is limited research to determine whether conservation tillage increases net C accretion versus simply altering the distribution of C content by soil depth. We implemented conservation farming practices (winter cover cropping plus strip tillage) for a nonirrigated corn (Zea mays L.) production system in the southeastern coastal plain of Georgia, United States, that had been previously managed under a conventional plow and harrow tillage regime. Total soil C and nitrogen (N) were measured on samples collected from 0 to 65 cm (0 to 25.6 in) at 57 sites before and after five years under conservation farming practices. Crop yield, winter and summer aboveground crop biomass production, and biomass C and N content were also measured annually at each site. Soil C increased an average of 20 Mg ha -1 (8.9 tn ac -1 ; 6 to 62 Mg C ha -1 (2.6 to 27.6 tn C ac -1 ), depending upon slope position) and was associated with a N increase of 2 Mg ha -1 (0.89 tn ac -1 ). Although 72% to 80% of the C accretion was in the top 35 cm (13.8 in), 3 to 6 Mg C ha -1 (1.3 to 2.6 tn C ac -1 ) was accreted from 35 to 65 cm (13.8 to 25.6 in). The soil C accreted during the study amounted to 36% of the net biomass C produced. Corn yield increased 2,200 kg ha -1 (1,964 lb ac -1 ) depending upon slope position (1,200 to 2,500 kg ha -1 (1,071 to 2,232 lb ac -1 )) during the same time. Analysis indicated that soil C content from 15 to 35 cm (5.9 to 13.8 in) was the soil parameter primarily associated with corn yield. Season rainfall from planting to corn silking stage for both corn production years was the lowest in the past 45 years (20 to 25 cm (7.8 to 9.8 in) below the net crop demand) suggesting that soil C-mediated increase in plant-available soil water was a mech- anism contributing to improved corn yield. Calculated estimates (from soil clay, sand, and C content) of increased soil water holding capacity suggest that C accretion in the top 35 cm (13.8 in) of soil potentially increased water storage enough to supply up to four days' worth of additional crop water demand. These results indicated that conservation farming practices can increase soil C and N accretion in degraded sandy soils of the humid southeastern United States coastal plain, and that increased soil C may potentially mitigate the deleterious effects of short-term rainfall deficits in nonirrigated production systems.

‘AC Harrow Crisp’ pears could be stored at 0 °C without or with a controlled atmosphere (18 or 2.5 kPa O2, 2 kPa CO2) for 111 d with little effect on overall quality. 1-Methylcyclopropene-treated fruit could be stored for longer periods under refrigerated air but not under a controlled atmosphere.

A field experiment was conducted in two different locations at Agricultural Research Station of Garmat Ali in Basrah-Iraq. The aim of this investigation is to evaluate the effective field capacity, field efficiency, draft force, pulverization index (PI), soil bulk density and soil porosity for moldboard plow (primary tillage), mounted disk harrow and offset disk harrow (secondary tillage) under different operating speed (2.54 (S1), 3.84 (S2) and 5.77 (S3) km hr-1) in two different soil textures (silty loam soil and clay soil). The design of the experiment was complete randomized blocks design in factorial experiment. The results showed that the moldboard plow had high values of draft force, pulverization index (PI) and soil porosity and lower soil bulk density, effective field capacity and field efficiency than that of mounted disk harrow and offset disk harrow in both soils. The operating speed and the interaction between operating speed and implements tillage type had significantly affect (p < 0.05) on all the studied parameters. The silty loam soil achieved higher effective field capacity, field efficiency, soil porosity (low bulk density) and considerable pulverization of soil clods than that of clay soil. The results also showed that the optimal operation conditions of implements tillage were associated with high operating speed of 5.77 km hr-1 in silty loam soil especially with using the disks harrow.

In the Jiloca valley (Teruel, Spain) saffron (Crocus sativus) is attracting attention because of its high quality and the growing demand in the gourmet market. To increase production the phytosanitary status needs to be guaranteed as well as the mechanization of the basic agronomic practices, especially weed control operations. Saffron is a perennial crop and weeding is especially important after flowering in mid of October until May when the aerial part disappears. Eight field trials were established to test the effect of flextine harrow, torsion and finger weeders. Torsion and finger weeders were difficult to adjust due to compact soils and steering problems. Efficacy for these tools was higher than 80% in two out of 12 occasions, only, while the flex-tine harrow exceeded this value in 7 occasions out of 18. The flextine harrow did no require adjustments on the row and could be used in an aggressive position because of the 20 cm plantation depth of the corms. Weeds including the Poaceae Lolium rigidum could be effectively controlled with the flextine harrow provided climatic conditions allowed treating immediately after flower harvest. Saffron flower and corm density were reduced by more than 40% after 3 cropping seasons without weed control compared to harrowing. Only slight differences were found in bulb size being higher for the harrowed plots. The use of the flex-tine harrow is highly recommended to reduce yield losses as well as to avoid weeds hosting viruses.

The area devoted to growing tobacco (Nicotiana tabacum L.) in the province of Granma, Cuba, accounted for nearly 2600 ha in the year 1997, which represented the 4% of the total tobacco plantation area on the island in that year. Tobacco is tillage-intensive since traditional production systems entail seven or eight cultivation operations before transplanting. The objective of this study was to evaluate two alternative tillage systems in comparison with conventional tillage for tobacco production with the aim to improve soil conditions, reduce the number of tillage operations for soil preparation for transplanting, and increase yields. The treatments studied were: (T1) conventional or traditional tillage, (T2) reduced tillage with a multi-tiller plough, and (T3) reduced tillage with a chisel plough. T1 consisted in disc ploughing twice and disc harrowing twice for primary tillage, while before transplanting plots were ploughed twice with a horse-drawn mouldboard plough and harrowed twice with a horse-drawn spike-tooth harrow. In T2 primary tillage was accomplished with two passes with the multi-tiller followed by disc harrowing twice before transplanting. In T3 chisel ploughing was substituted for multi-tiller ploughing. The two reduced tillage systems improved the physical conditions of the soil, which resulted in: lower bulk density, with average values across the 0-30 cm soil profile of 1.48, 1.34 and 1.30 Mg m-3 in T1, T2 and T3, respectively, at the end of the growing season; higher soil water content in the soil profile in all four sampling dates per season; greater porosity; and lower resistance to penetration with values of 2.48, 2.15 and 1.71 MPa in T1, T2 and T3, respectively, before crop harvesting. Tillage system T3 provided the highest crop yields (2.26 Mg ha-1) compared with T2 (2.14 Mg ha-1) and T1 (1.95 Mg ha-1), for the plants grown on T3 plots had the largest number of leaves. The size of the leaves was similar in all three systems, however.

Weed seed burial and excavation by tillage determines seed depth, seed survival, germination and pre-emergent seedling mortality. However, quantitative estimates of seed burial are available for only a few tools and often without reference to soil structure, moisture or tillage depth. This study proposes a conceptual model for predicting weed seed movements during superficial tillage in response to the type of tool, tillage depth and soil structure. The proposed model was calibrated with field data collected using coloured plastic beads as weed seed proxies. Beads were placed at different vertical and horizontal positions before tillage, using augers to preserve soil structure and collected after tillage by opening trenches and counting beads found at different depths. Approximately 33% of the beads were retrieved and used to establish bead distributions from which model parameters were estimated. Cross-validation showed that prediction quality was satisfactorily (modelling efficiency = 0.85, minimum rMSEP = 0.11) with most of the error associated with using a harrow in compacted soil. Subsequently, the new model was integrated into the existing weed dynamics model FlorSys , and simulations were run to predict weed emergence and dynamics for different tillage practices. With a surface seed bank, total emergence was highest for shallow operations (harrow, discs) and lowest for deep operations (chisel, mouldboard plough). Emergence was also lower in compacted soils. Differences among tillage tools persisted when weed dynamics were simulated over several years, with mouldboard ploughing generally having the lowest density even though this tool was only used every three years. Superficial tillage which left seeds closest to the soil surface resulted in the highest weed density. Also, for species with heavy seeds densities generally increased with ploughing. These simulations confirm the utility of the new model, but additional studies are needed to examine other tillage, management practices and weed species combinations.

The compact disc harrow due to post-harvest tillage is used to incorporate the stubble and plant residues into soil, to induce their decomposition and to increase mineralization. The high-cut winter rape stubble is often main challenge of clear disc harrowing, especially in clay loam soil at minimum expenditure of fuel consumption. The aim of this study was to find optimal tillage performances and determine the fuel consumption what required to achieve the preferred level of stubble tillage in loam and clay loam soil after winter oilseed rape harvest. The tillage quality and fuel consumption were investigated in dependence on harrow disc angle (10°, 15° and 20°), tillage depth (5 and 8 cm) and working speed (1.4; 1.9; 2.5; 3.1; 3.6 m∙s −1 ). The tractor “CASE 135″ was instrumented with data acquisition system and was used to measure fuel consumption, actual working speed and implement draft. Research developed the efficient adjustment of aggregate regime mode to the best soil structure and plant residue incorporation. The beneficial relationship was established by obtaining tillage quality level to fuel consumption, which varied from 2.6 to 5.9 L·ha −1 in depending of soil type (loam and clay loam). Based on research results, the optimal fuel consumption (2.85 L·ha −1 ) was identified at disk harrow adjustment: disc angle 10°, working speed 3.5 m∙s -1 on both soils, but in different tillage depth 8 cm on loam and 5 cm on clay loam soil.

Yu, K., Woodrow, L. and Poysa, V. 2015. AAC 26-15 soybean. Can. J. Plant Sci. 95: 441–443. AAC 26-15 is a high-yielding, high-protein, SCN resistant, food grade soybean cultivar with yellow hila and acceptable processing quality for foreign and domestic tofu and soymilk markets. It was developed at Agriculture and Agri-Food Canada (AAFC), Greenhouse and Processing Crops Research Centre (GPCRC), Harrow, Ontario. AAC 26-15 is adapted to areas of southwest Ontario with 3100 or more crop heat units and has a relative maturity of 2.3 (MG 2.3).

Information regarding the evaluation of tillage effects on soil properties and rainfed wheat (Triticum aestivum L.) cultivars of Iranian fields is not available. Therefore, this research was conducted in Sanandaj (west of Iran) using a randomized complete block design in a split-plot arrangement. Three types of tillage including conventional tillage (moldboard plow to soil depth of 30 cm plus disk harrow twice), minimum tillage (chisel plow to soil depth of 15 cm plus disk harrow once) and no-tillage are assigned to the main plots. Wheat cultivars (Sardari and Azar2) were randomly distributed within the subplots in each tillage system. Results showed that the greatest bulk density and cone index were found in the minimum tillage and no tillage systems. The highest rate of grain yield was obtained in the minimum tillage system. The grain yield of Sardari cultivar (1624.1 kg ha−1) was significantly greater than that of Azar2 (1572 kg ha−1). Minimum tillage improved soil physical properties and wheat growth ...

Open-air crops are important in Spanish horticulture. The limited number of herbicide active ingredients in minor crops, the waste problem of polyethylene (PE) plastic mulch and the high prices of biodegradable plastics leave hand-weeding and mechanical weed control as the most viable weed control methods. Different tools have been tested in northern European countries but their performance remains unknown in the edaphoclimatic situation of southern Europe. The objective of this work was to test novel physical weed control methods on processing tomato in northeastern Spain compared with other effective control methods, i.e., plastic and paper mulches. A first sequence of field trials was established from 2005 to 2008 at Zaragoza (Spain) to select the best physical control methods out of flamer, torsion weeder, finger weeder, flex-tine harrow and brush hoe used alone or in combination. The best method was the brush hoe which was then compared from 2009 to 2011 with PE mulch, biodegradable plastic mulch and paper mulch. Flamer, flex-tine harrow, torsion weeder and finger weeder performed quite irregularly due to crusty soil conditions and needed additional tools or repeated treatments to increase weed control efficacy. The brush hoe performed best in this soil situation working at about 5 cm depth. Weed biomass reduction was higher than 80% in 6 out of 7 years and similar yield was obtained in the brushed plots compared to the yield obtained with PE, biodegradable plastic and paper mulch. The brush hoe is thus a suitable option for weed control in processing tomato while the other tools were too weak to control aggressive summer weeds in the tested conditions.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:30:35Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:48:51Z : No. of bitstreams: 1 2-s2.0-84884215952.pdf: 574267 bytes, checksum: 2caa9a4c74c7454ff1f47c84e0b4e153 (MD5) Made available in DSpace on 2014-05-27T11:30:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-09-01 Appropriate management of agricultural crop residues could result in increases on soil organic carbon (SOC) and help to mitigate gas effect. To distinguish the contributions of SOC and sugarcane (Saccharum spp.) residues to the short-term CO2-C loss, we studied the infl uence of several tillage systems: heavy offset disk harrow (HO), chisel plow (CP), rotary tiller (RT), and sugarcane mill tiller (SM) in 2008, and CP, RT, SM, moldboard (MP), and subsoiler (SUB) in 2009, with and without sugarcane residues relative to no-till (NT) in the sugarcane producing region of Brazil. Soil CO2-C emissions were measured daily for two weeks after tillage using portable soil respiration systems. Daily CO2-C emissions declined after tillage regardless of tillage system. In 2008, total CO2-C from SOC and/or residue decomposition was greater for RT and lowest for CP. In 2009, emission was greatest for MP and CP with residues, and smallest for NT. SOC and residue contributed 47% and 41%, respectively, to total CO2-C emissions. Regarding the estimated emissions from sugarcane residue and SOC decomposition within the measurement period, CO2-C factor was similar to sugarcane residue and soil organic carbon decomposition, depending on the tillage system applied. Our approach may define new emission factors that are associated to tillage operations on bare or sugarcane-residue-covered soils to estimate the total carbon loss. UNESP/FCAV, Via de Acesso Prof. Paulo Donato Castellane, s/n, 14884-900, Jaboticabal, SP ARS/USDA North Central Soil Conservation Research Lab, 803 Iowa Ave, Morris, MN 56267 UNESP/FCAV, Via de Acesso Prof. Paulo Donato Castellane, s/n, 14884-900, Jaboticabal, SP

Microbial diversity can be used to assess the impact of agricultural practices on the long-term sustainability of cropping systems. The aim of this study was to investigate changes in soil bacterial diversity as a result of the impact of different soil tillage and crop rotation systems in an oxisol of southern Brazil. Bacterial diversity was examined in the 0- 10 cm layer in two field experiments by analyzing soil DNA using 16S rDNA-DGGE profiles. Experiment one consisted of a long-term 26-year trial with four soil tillage management systems: (1) no-tillage (NT), (2) disc plow (DP), (3) field cultivator (FC), and (4) heavy-disc harrow (DH), all under soybean (summer)/wheat (winter) crop succession. Experiment two consisted of a short-term 10-year trial with DP and NT and three crop rotations (CR) including grasses, legumes and green manures. Cluster analysis of the 16S rDNA sequences revealed that the main effect on clustering was attributed to differences in soil tillage management systems. The Shannon index confirmed greater bacterial diversity under NT, fol- lowed by the FC, DH and DP. Therefore, diversity decreased as tillage practices intensified. The evenness index demon- strated uniformity of the profiles of the bacterial communities, with dominance of a few communities, regardless of soil tillage and crop rotation. Different crop rotations had only minor effects on bacterial diversity, what could be related to a previous fallow period. The results suggest that bacterial diversity analyzed by DGGE may be useful as bioindicator of the changes caused by soil tillage.