Različiti sustavi obrade tla i njihov utjecaj na formiranje prinosa usjeva i posliježetvene ostatke

The long-term viability of Canadian prairie agriculture depends on the ability to arrest soil degradation caused by wind and water erosion and excessive tillage. The challenge is to develop crop-production systems that are economically viable and environmentally sustainable. The objective of this study was to quantify the short-term economic performance of field pea (Pisum sativium L.), flax (Linum usitatissimum L.) and spring and winter wheat (Triticum aestivum L.) grown under three tillage-management systems. The economic analysis was based on a tillage × crop rotation experiment started in 1986 and involving zero tillage (ZT), minimum tillage (MT) and conventional tillage (CT) and three 4-yr crop rotations. The economic analysis considered only costs associated with purchased inputs and machinery. The effects of method of tillage management on herbicide and fuel use were also determined for each crop. Costs of production were similar for all tillage systems and crop types. Net returns were higher for field pea, flax and spring wheat grown on stubble using ZT and MT than when CT was used, because of higher grain yields. Net returns were similar for winter wheat grown on stubble and for spring wheat grown on fallow for all tillage-management systems. Fuel consumption was highest for CT, intermediate for MT and lowest for ZT for all crops except winter wheat. In contrast, herbicide use was greater for ZT and MT than for CT for al crops except winter wheat; no differences were observed among tillage systems for this crop because it was always seeded directly into standing stubble. The shift from CT to ZT or MT systems did not increase costs of production or reduce short-term economic returns. ZT and MT had higher production potential than CT because increased soil-moisture conservation generally provided higher net returns. ZT used less fuel but more herbicides than MT and CT. Key words: Stubble cropping, fallow cropping, zero, minimum, conventional

The effect of tillage intensity and time of herbicide application on weed communities and populations in maize in central Europe

Long-term (1983–2012) assessment of three tillage systems on the energy use efficiency, crop production and seeding emergence in a rain fed cereal monoculture in semiarid conditions in central Spain

The effect of tillage systems (TS) on wheat quality traits including grain yield, thousand-kernels weight, hectoliter mass, flour extraction rate and flour rheological properties were evaluated. Five different TS were compared in winter wheat (Triticum aestivum L.) production on one experimental field (chernosem) located in the Baranya region, north-eastern Croatia from 1998 to 2001. Tillage systems included conventional tillage (CT), disc harrowing, fine till (DHF), soil loosening (SL) + disc harrowing (DH), disc harrowing, coarse till (DHC) and no-tillage (NT). The most stable grain yield was obtained by DHF and CT in all three experimental years. There was no striking regularity with regard to applied TS and hectoliter mass and thousand-kernels weight. The biggest difference of hectoliter mass was determined between CT and NT. TS had significant influence on the flour extraction rate in all three experimental years. The influence of TS on farinographic parameters was significant for all three experimental years for the quality number. Quality number was greater under CT than under other TS. Tillage effect on extensographic and amylographic parameters in the 3-year average did not show statistically significant differences. To sum up, since disc harrowing (DHF) and (DHC) followed by soil loosening with chisel produced equal grain yield and wheat quality parameters were slightly better than conventional tillage, these systems could be presented as an even handed replacement for ploughing.

Evaluating spectral indices for determining conservation and conventional tillage systems in a vetch-wheat rotation

Soft red winter wheat (Triticum aestivum L.) producers in the southeastern USA are adopting no-till production practices. Official wheat cultivar testing programs, however, are conducted in conventional-till. The objective of this research was to determine whether soft red winter wheat cultivars perform differently across tillage systems, indicating the need for no-till cultivar testing programs. Twelve winter wheat cultivars commonly produced in the southeastern USA were tested in a split-plot design with tillage system as the main effect. The test was located in the North Carolina Piedmont and Coastal Plain in 1996 and 1997. In the Piedmont the soil type was Hiwassee clay loam (fine, kaolinitic, thermic Typic Rhodudults), and in the Coastal Plain the soil was Goldsboro sandy loam (fineloamy, siliceous, subactive, Aquic Paleudults). Plant density after emergence, head density at harvest, kernel weight, grain yield, and test-weight were determined and compared across cultivars and tillage systems. For each of these variables, environment and cultivar effects were significant (P ≤ 0.05). Tillage system had a significant effect only on plant density with average no-till stands being 8.3 % lower than those in the conventional-till system. Relative cultivar performance, or rank, did not change across tillage systems for any of these variables. Consequently, soft red winter wheat cultivars that perform well in conventional-till will probably be the best adapted for no-till production. Separate cultivar trials are not required for the two tillage systems.

Soil carbon sequestration and stratification in a cereal/leguminous crop rotation with three tillage systems in semiarid conditions

Production of winter wheat (Triticum aestivum L.) under no‐till (NT) can have economic and edaphic benefits over conventional tillage (CT) systems, although in some years it can result in lower yields. Analysis of yield‐formation processes of wheat grown under NT and CT systems may elucidate why yields are sometimes lower under NT. The objective of this study was to determine the effects of tillage systems on yield‐formation processes of soft red winter wheat. Two experiments were conducted at two locations in Kentucky using randomized complete block split‐plot designs. Main plots in both experiments were two tillage systems (NT and CT). In Exp. 1, which was conducted in 2004, split plots were four cultivars with different heading dates. In Exp. 2, which was conducted in 2005 and 2006, the split and split‐split plots were two cultivars and three seeding rates, respectively. Total plant biomass, grain yield, yield components, and harvest index (HI) were measured at maturity. Grain yield was lower under NT than under CT in two of the five location/years. Neither cultivar differences in days to heading nor seeding rates altered the impact of NT on grain yield. The dominant response of soft red winter wheat to NT in this study was to increase tillering and reduce HI. The increased tillering growth habit due to NT could increase internal competition for assimilates, thereby diverting assimilates away from grain production to vegetative growth and reducing HI. The reduction in HI led in some years to a reduction in yield.

An experiment with five different tillage systems and their influence on physical properties of a silty loam soil (Albic Luvisol) was carried in northwest Slavonia in the period of 1997–2000. The compared tillage systems were: 1. conventional tillage (CT), 2. reduced tillage (RT), 3. conservation tillage I (CP), 4. conservation tillage II (CM), 5. no-tillage system (NT). The crop rotation was soybean (Glycine max L.) – winter wheat (Triticum aestivum L.) – soybean – winter wheat. Differences between tillage systems in bulk density, total porosity, and water holding capacity and air capacity were not significant in winter wheat seasons. In soybean seasons, significant differences between some tillage systems were recorded in bulk density, total porosity, air capacity and soil moisture. The deterioration trend of physical properties was generally increasing in the order CM, CT, CP, NT and RT. The highest yield of soybean in the first experimental year was achieved under CT system and the lowest under CP system. In all other experimental years, the highest yield of winter wheat and soybean was achieved under CM system, while the lowest under RT system.

Changes in soil carbon (C) and nutrients considerably influence soil health and agricultural sustainability. However, how agricultural management affects C and N allocation among various soil organic matter pools and their linkages with soil health are not clear for arid and semi‐arid regions. This study aimed to evaluate the soil profile distribution of selected C and N fractions and associated soil health properties in conventional tillage (CT), no‐tillage (NT), and strip tillage (ST) fields and quantify the relationship of labile and inorganic C and N fractions to soil organic carbon (SOC) sequestration in semi‐arid dryland cropping systems. Crop rotation was a 4‐year cycle of corn ( Zea mays L.)—sorghum ( Sorghum bicolor L. Moench)—winter wheat ( Triticum aestivum L.)—fallow across all tillage systems. Soil samples were collected from 0–20, 20–40, and 40–60 cm depths of each plot in July 2022, after 9 years of plot establishment, and analysed for potentially mineralizable carbon (PMC), microbial biomass carbon (MBC), SOC, soil inorganic (SIC), soil total carbon (STC), soil inorganic nitrogen (SIN), total labile nitrogen (TLN), total organic nitrogen (SON), and labile organic nitrogen (LON) and other soil health indicators. The results indicate that PMC was 31% more and LON was 23% more in NT than in CT, whilst ST resulted in lower pH and had only 10%, 9%, and 24% more SON, STN, and LON, respectively, than CT in 0–60 cm profile. The SIC stock was negatively correlated with MBC, PMC, SON, STN, LON, TLN, and SIN, whilst positively correlated with depth, STC, and pH. After 9 years of conservation tillage, whilst depth‐wise distribution varied among tillage systems, soil C sequestration rate was negative in the 0–60 cm profile under both NT and ST compared with CT, mainly owing to more SIC accumulation in deeper depth of conventional system. These results show the complexity of soil C and N allocation under different tillage systems, with NT and ST supporting greater C and N storage in the surface soil and CT supporting more C and N storage in the deeper depth. Soil biological activity indicators appear to drive surface SOC accumulation, whilst soil pH and N availability influenced SIC accumulation in lower depths.

Long-term effects of tillage systems and rotations on soil structural stability and organic carbon stratification in semiarid central Spain

Soil C sequestration can improve soil quality and reduce agriculture's contribution to CO 2 emissions. The long‐term (12 yr) effects of tillage system and N fertilization on crop residue production and soil organic C (SOC) sequestration in two dryland cropping systems in North Dakota on a loam soil were evaluated. An annual cropping (AC) rotation [spring wheat (SW) ( Triticum aestivum L.)–winter wheat (WW)–sunflower (SF) ( Helianthus annuus L.)] and a spring wheat‐fallow (SW‐F) rotation were studied. Tillage systems included conventional‐till (CT), minimum‐till (MT), and no‐till (NT). Nitrogen rates were 34, 67, and 101 kg N ha −1 for the AC system and 0, 22, and 45 kg N ha −1 for the SW‐F system. Total crop residue returned to the soil was greater with AC than with SW‐F. As tillage intensity decreased, SOC sequestration increased (NT > MT > CT) in the AC system but not in the SW‐F system. Fertilizer N increased crop residue quantity returned to the soil, but generally did not increase SOC sequestration in either cropping system. Soil bulk density decreased with increasing tillage intensity in both systems. The results suggest that continued use of a crop‐fallow farming system, even with NT, may result in loss of SOC. With NT, an estimated 233 kg C ha −1 was sequestered each year in AC system, compared with 25 kg C ha −1 with MT and a loss of 141 kg C ha −1 with CT. Conversion from crop‐fallow to more intensive cropping systems utilizing NT will be needed to have a positive impact on reducing CO 2 loss from croplands in the northern Great Plains.

Economic evaluation of tillage management practices at the watershed scale in southern Manitoba

Conservation agriculture (CA) does have several advantages over conventional tillage (CT) based agriculture in terms of soil health parameters. However, weeds are the major biotic constraint in CA, posing as a great challenge towards its adoption. Field experiment was conducted at Directorate of Weed Research , Jabalpur (MP) during 2012–14 to monitor weed dynamics, crop productivity, and soil health parameters in a rice (Oryza sativa L.)-wheat (Triticum aestivum L.)-greengram [Vigna radiate (L.) Wilczek] cropping sequence under CA system. The treatments consist of ZT (DSR)+Sesbania brown manuring – ZT (wheat) – ZT (greengram), with or without crop residue cover; CT (DSR)+Sesbania brown manuring – CT (wheat) – ZT (green gram), with or without crop residue cover; farmers practice, i.e. CT (TPR) – CT (wheat). The lowest total weed density was recorded under ZT (DSR)+Sesbania. Compared to CT, significantly lower density of Cyperus iria, but higher density of Caesulia axillaris was recorded under ZT; while CT (TPR) recorded the lowest population of P. minima and D. retroflexa during rice. Similarly, in wheat, significantly lower population of Phalaris minor and Chenopodium album was noticed under ZT. Highest grain yield (3.42 t/ha) was recorded with transplanted rice; whereas, higher yield of wheat was recorded when sown after DSR and crop residues were recycled. Tillage systems did not differ significantly in terms of soil respiration rate when crop residues were recycled. There was significant gain in soil organic carbon pool only when the complete conservation package of ZT along with crop residue recycling was adopted. A preliminary survey conducted in the adjoining localities of Jabalpur during 2012-13 showed lack of awareness among the farmers about the resource conservation technology (RCT) to grow wheat. Subsequently, the trials laid out in 3 farmers’ field during rabi seasons of 2012-13 and 2013-14 also showed that wheat performed much better under CA, as compared to the conventional farmers’ practice, resulting in lower cost of production, higher income and higher benefit: cost ratio. Green gram, sown with RCTs and chemical weed control measure in the same farmers’ fields following wheat, also provided higher B:C ratio and an additional net return of `28 975/ha over farmers practice. It was concluded that the RCTs like ZT and residue cover could be practiced in the black cotton soils to increase farmers’ income.

In this study, we aimed to determine the effects of tillage systems (TS) on wheat grain yield, yield components, and physicochemical properties under rain-fed conditions over 2 years (2018–2019) in the Kuhdasht region in southwestern Iran. The tillage treatments were a combination of conventional tillage (CT), reduced tillage (RT), and no tillage (NT) systems based on randomized complete blocks with three replications. Wheat grain yields and yield components, physical properties (geometrical dimensions, sphericity, thousand-grain mass (TGM), water absorption (WA), volume (V), and density), chemical composition (protein content (PC), water content (WC), fiber content (FC), ash content (AC)), surface color parameters (L*, a*, and b*), and correlations among measured parameters were assessed. The results showed that wheat grain yield and yield components were significantly affected by TS (p < 0.01). The wheat grain yield was higher under CT (2.72 t ha−1), with a significant difference between RT (1.76 t ha−1) and NT (1.20 t ha−1). The highest TGM (49.19 g) was achieved under CT, followed by RT (43.41 g), with the lowest (39.17 g) in the NT system. TS had significant effects on certain physical properties of wheat grains (p < 0.01). Wheat grain, size, shape, and mass values were higher under CT than RT and NT systems in all experimental years. CT resulted in the highest WA, while the lowest resulted from NT. TS had no significant influence on the density of the grains. TS had significant effects on PC, AC, and WC values of grains at the 1% probability level and on FC at the 5% level. Higher PC values were obtained under the CT system (13.07%, against 11.90% and 10.67% for RT and NT, respectively) in all growing seasons. Additionally, the AC was significantly lower in the sample grains under RT (2.38%) and NT (2.43%) than in those from CT (2.56). The FC was higher under NT (15.73%) than RT (13.73) and CT (13.71%). The grain WC was significantly higher under NT (7.57%) than RT (6.79%) and CT (7.0%). The TS significantly affected the surface color parameters of grains, while the L* (lightness) and b* (yellowness) values of grains under CT were higher than in RT and NT.