The delivery of food security via continued crop yield improvement alone is not an effective food security strategy, and must be supported by pre- and post-border biosecurity policies to guard against perverse outcomes. In the wake of the green revolution, yield gains have been in steady decline, while post-harvest crop losses have increased as a result of insufficiently resourced and uncoordin...

Accurate and timely information on rice crop growth and yield helps governments and other stakeholders adapting their economic policies, enables relief organizations to better anticipate and coordinate relief efforts in the wake of a natural catastrophe, and provides technical backbone of an insurance solution where risks of yield losses from the rice smallholders are transferred to the insuran...

Plant-parasitic nematodes are major constraints to the productivity of tropical farming operations. Intensive land use and climatic conditions favorable to nematode development contribute to increased crop losses due to these pests. Many farmers in developing tropical countries have limited resources and management options. Cropping systems research is a relatively low-cost, low-input method of...

Soil carbon changes were modelled over 30 years with the focus on cereal crops, since leys are often managed similarly in organic and conventional agriculture. Other crops were not considered due to difficulties in large-scale cropping of oilseed rape and potatoes organically because of pest problems. Four scenarios were used: 0%, 8% (current), 20% and 100% organic cereal production. Conversion...

In situ volumetric soil-water contents were measured on 11 days at 0.20 m depth intervals to 1.0 m in a field experiment with four replicates of a dry-land corn hybrid (Pioneer 3140) at plant populations of 37, 49, and 62 thousand plants haÿ1. These measurements were used to estimate total soil-water losses in each of the 12 field plots for each of the 10 measurement intervals. The area of the ...

Model projections suggest that although increased temperature and decreased soil moisture will act to reduce global crop yields by 2050, the direct fertilization effect of rising carbon dioxide concentration ([CO2]) will offset these losses. The CO2 fertilization factors used in models to project future yields were derived from enclosure studies conducted approximately 20 years ago. Free-air co...

Nitrification inhibitors (NIs) delay the oxidation of ammonium by soil microorganisms, maintaining a higher proportion of applied nitrogen (N) in the soil by preventing nitrate-N loss from leaching and gaseous N losses from nitrification and denitrification. Thus, a large number of studies have shown N fertilizers with NIs are more environmentally friendly. In contrast, there are only a lim...

A baseflow survey of 41 tributary creeks investigated the tiansport of alrazine, nilrate-nitrom chloride and sulfate in two 5,000 ha Jasper County, Iowa watersbeds. The waterskds comprise a long-tam paired shldy to evaluate the effects of largesale conversion of row nop to prairie in Walnut creek watershed compared to highly agricultural Squaw creek watershed. Discharge and chemical concentrati...

Various spoilage microorganisms (bacteria, yeasts and molds) readily grow on crops going into a silo, causing losses in dry matter and quality. To prevent these various microorganisms from growing, two conditions are needed in the silo: an oxygen-free (or anaerobic) environment and a low pH. Many of the oxygen-requiring (aerobic) microorganisms that heat the silage as well as causing losses can...

The need for precise and responsive management of N fertilizer in corn production is compelling for both economic and environmental reasons, but the optimum N rate remains an elusive notion. Economically optimal N rates (EONR) in much of North America may range from zero to 225 lb/A (Scharf et al., 2006; Sawyer et al. 2006), and may vary as the growing season progresses (van Es et al., 2007). M...