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Tillage Systems (tillage + system)
Selected AbstractsAdvantages of Different Tillage Systems and Their Effects on the Economically Important Pests, Thrips tabaci Lind. and Aphis gossypii Glov. in Cotton FieldsJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 6 2004I. Gencsoylu Abstract An experiment to assess advantages of different tillage and their effects on Aphis gossypii Glov. and Thrips tabaci Lind was conducted during the 2000 and 2001 cotton growing seasons in cotton fields at Adnan Menderes University, Agricultural Faculty Research Center, located in Ayd,n Province, Turkey. The tillage systems examined were conventional, strip, precision and ridge tillage. Two insect population densities were not affected by the type of tillage systems during either year. However, significant differences in populations were observed in thrips populations on 31 May 2000 and 18 May 2001 and aphid populations on 24 May 2000 and 11 May 2001. The results show that the highest yield was observed in all conservation tillage systems in 2000 and ridge tillage system in 2001. Early maturity was higher in both precision and ridge tillage systems. In addition, tillage systems did not affect fibre properties. As a result, the application of conservation tillage is more advantageous in cotton in respect of early maturity and total yield. [source] Evaluation of the SWEEP model during high winds on the Columbia Plateau ,EARTH SURFACE PROCESSES AND LANDFORMS, Issue 11 2009G. Feng Abstract A standalone version of the Wind Erosion Prediction System (WEPS) erosion submodel, the Single-event Wind Erosion Evaluation Program (SWEEP), was released in 2007. A limited number of studies exist that have evaluated SWEEP in simulating soil loss subject to different tillage systems under high winds. The objective of this study was to test SWEEP under contrasting tillage systems employed during the summer fallow phase of a winter wheat,summer fallow rotation within eastern Washington. Soil and PM10 (particulate matter ,10 µm in diameter) loss and soil and crop residue characteristics were measured in adjacent fields managed using conventional and undercutter tillage during summer fallow in 2005 and 2006. While differences in soil surface conditions resulted in measured differences in soil and PM10 loss between the tillage treatments, SWEEP failed to simulate any difference in soil or PM10 loss between conventional and undercutter tillage. In fact, the model simulated zero erosion for all high wind events observed over the two years. The reason for the lack of simulated erosion is complex owing to the number of parameters and interaction of these parameters on erosion processes. A possible reason might be overestimation of the threshold friction velocity in SWEEP since friction velocity must exceed the threshold to initiate erosion. Although many input parameters are involved in the estimation of threshold velocity, internal empirical coefficients and equations may affect the simulation. Calibration methods might be useful in adjusting the internal coefficients and empirical equations. Additionally, the lack of uncertainty analysis is an important gap in providing reliable output from this model. Published in 2009 by John Wiley & Sons, Ltd. [source] Tillage affects the activity-density, absolute density, and feeding damage of the pea leaf weevil in spring peaENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2010Timothy D. Hatten Abstract Conversion from conventional-tillage (CT) to no-tillage (NT) agriculture can affect pests and beneficial organisms in various ways. NT has been shown to reduce the relative abundance and feeding damage of pea leaf weevil (PLW), Sitona lineatus L. (Coleoptera: Curculionidae) in spring pea, especially during the early-season colonization period in the Palouse region of northwest Idaho. Pitfall traps were used to quantify tillage effects on activity-density of PLW in field experiments conducted during 2001 and 2002. As capture rate of pitfall traps for PLW might be influenced by effects of tillage treatment, two mark-recapture studies were employed to compare trapping rates in NT and CT spring pea during 2003. Also in 2003, direct sampling was used to estimate PLW densities during the colonization period, and to assess PLW feeding damage on pea. PLW activity-density was significantly lower in NT relative to CT during the early colonization period (May) of 2001 and 2002, and during the late colonization period (June) of 2002. Activity-density was not different between treatments during the early emergence (July) or late emergence (August) periods in either year of the study. Trap capture rates did not differ between tillage systems in the mark-recapture studies, suggesting that pitfall trapping provided unbiased estimates of PLW relative abundances. PLW absolute densities and feeding damage were significantly lower in NT than in CT. These results indicate that NT provides a pest suppression benefit in spring pea. [source] Soil Conservation Tillage Effects on Yield and Water Use Efficiency on Irrigated Crops in Central ItalyJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2008R. Casa Abstract Despite possible agronomic and environmental benefits, the diffusion of soil conservation tillage systems in Italy is currently rather low. The aim of this study was to compare the performance of different soil tillage techniques, in an effort to identify suitable soil management options for irrigated crops in Central Italy. An experiment was carried out on maize and soybean from April to October in two consecutive years (1993 and 1994) in Maccarese (a coastal location near Rome). The systems compared were: conventional mouldboard ploughing (CT), minimum tillage, ridge tillage and no-tillage (NT). In 1993, actual crop evapotranspiration was measured throughout the growing season on NT and CT soybean, using a micrometeorological technique. No significant differences due to soil tillage were found for grain yield and yield irrigation water use efficiency (IWUEy), except for soybean in 1994, in which yields and IWUEy were 59 % higher on conservation tillage treatments compared with CT. In 1994 soybean yield water use efficiency was 10.1 and 9.5 kg ha,1 mm,1 for NT and CT respectively. The results suggest that the adoption of soil conservation tillage is feasible, for the specific cropping system, with equivalent or better performances as conventional tillage. [source] Impact of Soil Tillage and Crop Rotation on Barley (Hordeum vulgare) and Weeds in a Semi-arid EnvironmentJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 6 2004H. Z. Ghosheh Abstract Experiments were conducted to evaluate the effect of mouldboard- or chisel-ploughing and rotations on barley crops and associated weeds in a semi-arid location. Two primary soil tillage operations and eight crop rotation-tillage operation combinations were evaluated over two successive seasons. Drought conditions prevailed (<152 mm annual precipitation) and affected the measured parameters. Barley grown in mouldboard-ploughed plots had higher biomass compared with chisel-ploughed plots. Barley grain yield was greater in mouldboard-ploughed plots in a fallow-fallow-barley rotation. Weed species densities varied between tillage systems and rotations. Density of Hordeum marinum, for example, was high in fallow-barley-fallow in chisel-ploughed plots, and was high under more continuous fallow in mouldboard-ploughed plots. Similar variations were also observed in weed fresh weights and in numbers of seed produced. The results describe the productivity of barley under extremely dry conditions, where an advantage for mouldboard ploughing was observed. The results also indicate the complexity of weed communities in their response towards different tillage-rotation combinations. [source] Advantages of Different Tillage Systems and Their Effects on the Economically Important Pests, Thrips tabaci Lind. and Aphis gossypii Glov. in Cotton FieldsJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 6 2004I. Gencsoylu Abstract An experiment to assess advantages of different tillage and their effects on Aphis gossypii Glov. and Thrips tabaci Lind was conducted during the 2000 and 2001 cotton growing seasons in cotton fields at Adnan Menderes University, Agricultural Faculty Research Center, located in Ayd,n Province, Turkey. The tillage systems examined were conventional, strip, precision and ridge tillage. Two insect population densities were not affected by the type of tillage systems during either year. However, significant differences in populations were observed in thrips populations on 31 May 2000 and 18 May 2001 and aphid populations on 24 May 2000 and 11 May 2001. The results show that the highest yield was observed in all conservation tillage systems in 2000 and ridge tillage system in 2001. Early maturity was higher in both precision and ridge tillage systems. In addition, tillage systems did not affect fibre properties. As a result, the application of conservation tillage is more advantageous in cotton in respect of early maturity and total yield. [source] Effect of Different Levels of Wheat Straw Soil Surface Coverage on Weed Flora in Vicia faba CropsJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2003D. Bilalis Abstract The crop system implemented on organic farms requires that crop residues are incorporated into the soil following the end of wheat cultivation. This system leads to a reduction in soil moisture and the creation of favourable conditions for the emergence of weeds. In contrast, covering the soil with 60 % crop residues was found to maintain soil moisture and lead to a reduction in dry weed mass, population density and population frequency as well as a reduction in population diversity, regardless of the initial weed flora before the implementation of different soil tillage systems. Finally, an increase in the prevalence of broad-leafed weeds was observed as the level of soil cover increased. [source] Responses of phosphatases and arylsulfatase in soils to liming and tillage systemsJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 3 2003Mine Ekenler Abstract This study was carried out to investigate the long-term influence of lime application and tillage systems (no-till, ridge-till, and chisel plow) on the activities of phosphatases and arylsulfatase in soils at four research sites in Iowa, USA. The activities of the following enzymes were studied: acid and alkaline phosphatases, phosphodiesterase, and arylsulfatase at their optimal pH values. With the exception of acid phosphatase, which was significantly (P < 0.001) but negatively correlated with soil pH (r ranged from ,0.65** to ,0.98***), the activities of other enzymes were significantly (P < 0.001) and positively correlated with soil pH, with r values ranging from 0.65** to 0.99*** for alkaline phosphatase, from 0.79*** to 0.97*** for phosphodiesterase, and from 0.66*** to 0.97*** for arylsulfatase. The , activity/, pH values were calculated to determine the sensitivity of each enzyme to changes in soil pH. Acid phosphatase was the most sensitive and arylsulfatase the least sensitive to changes in soil pH. Activities of the enzymes were greater in the 0 , 5,cm depth samples than those in 0 , 15,cm samples under no-till treatment. With the exception of acid phosphatase, enzyme activities were mostly significantly (P < 0.001) and positively correlated with microbial biomass C (Cmic), with r values ranging from 0.28 (not significant) to 0.83*** and with microbial biomass N (Nmic), with r values ranging from 0.31 (not significant) to 0.94***. Liming and tillage systems significantly affected the activities of some enzymes but not others, as was evident from the specific activity values (g of p -nitrophenol released kg,1 Corg h,1). Reaktionen von Phosphatasen und Arylsulfatasen in Böden auf Kalkung und differenzierte Bodenbearbeitung In vier langjährigen Feldversuchen in Iowa, USA, wurde der Einfluss von Kalkung und differenzierter Bodenbearbeitung (Direktsaatverfahren, reduzierte Bearbeitung und Grubberverfahren) auf die Aktivitäten von Phosphatasen und Arylsulfatase in Böden untersucht. Die Aktivitäten von saurer und alkalischer Phosphatase, Phosphodiesterase und Arylsulfatase wurden unter dem optimalen pH-Wert für das jeweilige Enzym bestimmt. Mit Ausnahme der sauren Phosphataseaktivität, welche signifikant negativ (P < 0.001) mit dem pH-Wert des Bodens korreliert war (r = ,0.65** bis ,0.98***), waren die Aktivitäten der anderen Enzyme signifikant (P < 0.001) positiv mit dem Boden-pH korreliert. Dabei variierten die Korrelationskoeffizienten zwischen r = 0.65** und 0.99*** für die alkalische Phosphatase, zwischen r = 0.79*** und 0.97*** für die Phosphodiesterase und zwischen r = 0.66*** und 0.97*** für die Arylsulfatase. Die Verhältnisse von , Aktivität / , pH-Wert wurden berechnet, um die Empfindlichkeit der untersuchten Enzyme gegenüber pH-Wertveränderungen im Boden festzustellen. Dabei erwies sich die saure Phosphatase als das emfindlichste und die Arylsulfatase als das am wenigsten emfindlichste Enzym. In der Direktsaatvariante waren die Enzymaktivitäten in 0 , 5,cm Bodentiefe höher als in 0 , 15,cm Tiefe. Mit Ausnahme der sauren Phosphatase waren die Enzymaktivitäten signifikant positiv mit dem mikrobiell gebundenen C (Cmik) und N (Nmik) korreliert. Die Korrelationskoeffizienten variierten dabei zwischen r = 0.28 (nicht signifikant) und 0.83*** für Cmik und zwischen r = 0.31 (nicht signifikant) und 0.94*** für Nmik. Die spezifischen Enzymaktivitäten (g p -Nitrophenol kg,1 Corg h,1) zeigten, dass die Aktivitäten von einigen Enzymen signifikant von Kalkung und Bodenbearbeitungssystem abhängig waren. [source] Soil chemical quality changes and implications for fertilizer management after 11 years of no-tillage wheat production systems in semiarid MoroccoLAND DEGRADATION AND DEVELOPMENT, Issue 6 2001R. Mrabet Abstract A long-term experiment comparing no-till with conventional tillage systems across five rotations was evaluated 11 years after initiation. The objectives of the present paper are (1) to report differences in soil chemical properties (namely soil organic matter, total nitrogen, phosphorus, potassium and pH) that have resulted by converting from conventional to no-till under contrasting cropping systems and (2) to draw tentative conclusions and recommendations on fertility status and fertilizer use and management. Soil in the no-till system had increased surface soil organic C levels relative to conventional tillage regardless of rotation. In addition, depending on the rotation, the N and P content of the soil improved with no-till compared with conventional tillage. In other words, no-till has helped to retain soil organic matter (SOM), conserved more N, and resulted in increased extractable P and exchangeable K concentrations in the upper root-zone. Hence, wheat produced in a no-till system may receive more nutrients from decomposition of SOM and acidification of the seed zone. It is possible that lesser amounts of fertilizer nutrients will be needed because of the greater efficiency of nutrient cycling in no-till systems relative to conventional systems. Copyright © 2001 John Wiley & Sons, Ltd. [source] |