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Exploiting pathogens for the control of black grass, Alopecurus myosuroides - PS2153

Description
Bioherbicides can be based on naturally occurring pathogens of weed species to reduce weed populations or the competitive ability of weeds.. They may be used with or without conventional agrochemical products. Bioherbicides can be classed as “inundative”, where an organism is produced, formulated, and applied to the target weed, but long term survival of the biocontrol agent in the environment is not necessary or desirable. A “classical” approach releases an organism into the environment in the expectation of long term survival and continual downward pressure on the target weed population. This project will focus on the inundative approach and synergistic effects between potential bioherbicides, chemical and cultural approaches, for the control of black-grass, Alopecurus myosuroides.

Despite significant research and some commercial interest in bioherbicides in Europe, the number and range of developed products is still extremely limited. There are many reasons for this, including the cost and regulatory aspects of bioherbicide development, the logistical or technical issues surrounding introduction of pathogens into an arable environment with high usage of plant protection products, lack of selectivity of some products, and the overall tendency of bioherbicides to be non-lethal to targets. However, one of the main reasons for limited product development has hitherto been access to highly effective and relatively low cost chemical herbicides.

This situation has now changed significantly in the case of black-grass where significant levels of insensitivity to previously effective herbicides have built up, resulting in control failure in some areas. Moreover, shifts in tillage practice and limited rotational options have contributed to increased black-grass problems, to the extent that the species is now one of the major constraints on cereal production. It is against this background that this proposal seeks to identify bioherbicide agents which will have significant impact on the return of viable black-grass seed to the soil. The relevance to policy lies in potential reduction of chemical active ingredient levels, extending the useful life of partially effective products, and ensuring that cultivation and rotational practices which have other environmental and economic benefits can be maintained in balance with effective control of black-grass. The project will seek to establish ways in which potentially effective organisms could be used in arable systems. Industry engagement will take place during the life of the project to ensure that outcomes can be reviewed and promising leads made available promptly for further development.

The project will utilize known records of pathogens on A. myosuroides, but will also conduct searches through the season at sites with high A myosuroides populations, and use seed collections from these and other sources to identify seed-borne organisms. Records of pathogens on other Alopecurus species will also be investigated. Some of these species are of agricultural interest (eg Alopecurus pratensis - meadow foxtail ) or ornamental (eg Alopecurus lanatus - woolly foxtail) and where pathogens have been recorded, host range testing which includes the weedy A. myosuroides has seldom been carried out.

Objective
1) To determine whether pathogens of A myosuroides have the ability to reduce seed production and/or seed viability
Project Documents
• EVID4 - Final project report : PS2153 Final report   (260k)
Time-Scale and Cost
From: 2013

To: 2014

Cost: £75,000
Contractor / Funded Organisations
NIAB
Keywords
Biopesticide              
Herbicide use              
Pathogens              
Weeds              
Fields of Study
Pesticide Safety