Improved Management of Herbicides in Conservation Agriculture Systems Using Nuclear Techniques

The intensification of agriculture and changing climate conditions have led to an increased susceptibility of crops to weed and pest problems. Pest control methodologies are expected to change substantially in developed countries. Pesticide reduction programmes, such as integrated pest management (IPM), are in place in a number of countries, to decrease excessive use of pesticides. Despite these efforts to reduce pesticide use in agriculture, pesticides will remain a major tool. 'Pesticide' is a broad term, covering a range of products that are used to control pests in agriculture, such as insecticides, fungicides or herbicides (weed control). In particular with regards to herbicides there may be even an increase in its use in most developing countries because of increasing labour shortages in the rural areas. The use of herbicides is one of the potential factors that make agricultural intensification economically viable, hence improve food security.
Herbicides are globally the most commonly used crop protection agents. Glyphosate, Atrazine and 2,4-D are among the most frequently used herbicides for a number of crops. Additional pressure to produce biomass for food, fibre, feed and fuel makes it necessary to think more about the impact of herbicides on land productivity and farmers’ environment, and how to ensure the efficient use of herbicides.
Besides the expected increase in the use of herbicides particularly in developing countries, additional challenges to farmers appear on the horizon. Herbicide use plays a vital role in adopting conservation land and water management practices in various agro-ecosystems, such as conservation tillage and improved rice cropping systems. Sustainable use of herbicides in these systems not only achieves increased crop productivity and crop quality but also aims to mitigate the impacts of herbicides on soil quality and biodiversity. However, the interactions and feedback mechanisms between herbicides and soil parameters (e.g., soil carbon, soil nutrients, soil moisture and temperature dynamics) in agroecosystems that adopt the conservation land and water management practices, are poorly characterized. In addition, in many countries herbicide tolerance in weeds (in particular to glyphosate) is becoming a problem, forcing farmers to change their weed control strategies by diversifying herbicide use and improving cropping systems (crop rotations).
This CRP will provide improved understanding and quantification of these interactions under a variety of agro-ecosystems at various spatial scales (from field to catchment scale) for several important crop species using both nuclear and non-nuclear techniques, including the use of isotopically-labelled herbicides, fertilizers and crop residues (C-14, C-13 and N-15). This understanding is crucial in enhancing the efficient use of herbicides for food security and minimizing negative effects on soil biodiversity and water quality.
The proposed CRP is in synergy with the FEP-managed entitled “Integrated analytical approaches to assess indicators of the effectiveness of pesticides management practices at a catchment scale”.