to evaluate the effect of cover crops, tillage systems and nitrogen (n) application rates on yield of forage sorghum (cv. kfs3), a factorial–spilt plot arrangement based on randomized complete block design with four replications was carried out at the research farms college of agriculture and natural resources, university of tehran, karaj, during the growing seasons of years 2005 and 2006. comb...

The short-term responses of soil microbial processes and community structure to perturbation constitute one aspect of soil quality. Such responses are often associated with an increase in the emissions of greenhouse gases (i.e., CO2, NO, or N2O) and the accumulation and potential loss of nitrate by leaching. Here we describe our recent work on responses of soil carbon and nitrogen dynamics, mic...

Few studies have examined the water quality impact of manure use in no-tillage systems. A lysimeter study in continuous corn (Zea mays L.) was performed on Maury silt loam (fine, mixed, semiactive, mesic Typic Paleudalf) to evaluate the effect(s) of tillage (no-till [NT] and chisel-disk [CD]), nitrogen fertilizer rate (0 and 168 kg N ha(-1)), and dairy manure application timing (none, spring, f...

The effects of no-tillage (NT), conventional tillage (CT), and crop rotation on soybean yield and population dynamics of Heterodera glycines were compared during a 7-year study in a silty clay loam soil with 6% organic matter. Either H. glycines-resistant 'Linford' soybean or susceptible 'Williams 82' soybean was rotated with corn and grown on 76-cm-wide rows in both tillage systems. Soybean wa...

Soil erosion from agricultural lands can be reduced by adoption of conservation management practices. The objectives of this study were to investigate the effectiveness and cost-benefit of conservation management practices on sediment reduction under a corn–soybean rotation. The experimental site was 6.4 ha (15.8 ac) and located within the Four Mile Creek watershed in eastern Iowa. Management p...

Mechanized agriculture is increasing rapidly in the Cerrado region of Brazil, causing concerns about water quality, off-site impacts, and sustainability. Our objective was to determine the impact of tillage on soil biological activity and aggregate stability in an Oxisol typical to the region. Three different tillage practices common to the Cerrado region (no-till, disk harrow, and disk plow) a...

This work was aimed at assessing whether in silage maize it is possible to replace precisionplanting with a volumetric seeding in the perspective of developing hybrid machines to strip tilland sow both high density crops like winter cereals and low density crops like maize. This inorder to reduce the number of machines in the farm, simplify logistics and reduce amortizationcosts. Two experiment...

Simplified cultivation technologies for rice have become increasingly attractive in recent years in China because of their social, economical and environmental benefits. To date, several simplified cultivation technologies, such as conventional tillage and seedling throwing (CTST), conventional tillage and direct seeding (CTDS), no-tillage and seedling throwing (NTST), no-tillage and direct see...