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Microbial inoculents in agriculture and the environment

Objective

A. BACKGROUND

A.1. Current state of knowledge in the field

Inoculation of plants with beneficial bacteria and fungi has become an established agricultural practice over the last 100 years. Inoculants may specifically:

- improve host plant nutritional status and reduce the need for fertilizer inputs,

- suppress pests or diseases,

- or generally improve crop yields by a combination of effects.

In European agriculture the major inoculant is Bradyrhizobium japonicum, used for soybean. Other inoculants including B. lupini, Rhizobium meliloti, R. leguminosarum, Azospirillum, fluorescent pseudomonads and avirulent derivatives of Agrobacterium and Fusarium are potentially important. In forestry, pre-infection of young trees with ectomycorrizal fungi before planting out significantly improves their growth and survival. Inoculation of vegetables in soilless cultures and of container-grown ornamental plants and trees with vesicular-arbuscular (VA) mycorrhizal fungi is moving towards introduction on a commercial scale.

Besides these agricultural uses, microbial inoculants can also be utilized for soil and water bioremediation, offering new possibilities for natural resources protection and reclamation.

The use of microbial inoculants in agriculture and the environment is predicted to increase as the necessity to protect the environment and the consumer leads to reduction in chemicals inputs. For example, the "biopesticide" market would represent $600 million in 1998 (Silvy, 1995) and the potential Rhizobium market in the USA is $1 000 million (Stacey and Upchurch, 1984). The possibilities offered by Azospirillum inoculants on cereals (increase of 5-30% yield in 60-70% reported experiments, Okon et al., 1994) may open a new market of millions of hectares.

However, successful applications remain scarce except for legume inoculation (approximately 12.106 hectares inoculated worldwide for soybean) and a few biocontrol agents. A recent survey cited 30 products effective against soilborne diseases (Lumsden et al., 1995) and new inoculants were recently registered (Azospirillum inoculant in France, to improve the efficacy of nitrogen utilization by corn) but they represent a small part of the agro-chemical market. During the last decades, important scientific investments have been made into the use of microbial inoculants but without economic or social return.

Many of the basic concepts of biocontrol, plant growth promotion and soil bioremediation are known but potentially interesting new technologies remain at the laboratory level without any application.

This situation is not surprising as the use of microbial inoculants suffers from several limitations:

- proposed inoculation process are new technologies. They often have a poor efficiency in terms of reliability (suboptimal inoculation rate, poor survival of the micro-organisms during inoculation) and acceptability by farmers (compatibility with existing practices and pesticides, inoculant shelf-life),

- there is no link between specialists of different micro-organisms (Rhizobium, pathogen antagonists, plant growth promoting Rhizobacteria) even if they are faced with the same problems (inoculant technology, inoculation methods and fate of micro-organisms after inoculation),

- research scientists are reluctant to spend time on completing the development of a new inoculant because of the increasing pressure to "publish or perish",

- progress in soil microbial ecology started only 20 years ago compared with soil chemistry. However, the use of molecular biology techniques in applied ecology and micro-organisms engineering will offer new possibilities for the future.

A.2. Why the cooperation should be carried out within the context of COST

The orientation of the Common Agricultural Policy (CAP) of the European Community requires protection of the environment and natural resources (air, water and soils). There is also an increasing demand for "safe" agricultural products, with a decreasing use of chemicals (fertilizers and pesticides).

Inevitably agriculture must reconsider the management of soil micro-organisms as a possible alternative or complementary approach to designing new plant production systems with limited side-effects on the environment.

The use of microbial inoculants has proved to be an efficient and realistic alternative for legumes and for the control of some plant pests and diseases. The problem now is to develop new microbial technologies in a complex situation:

- markets remain to be created. They will be, at the beginning niche markets, too small for development by large companies. Smaller companies are involved but have a limited capacity to invest. Incentive help from authorities and/or public research laboratories, will be necessary to develop this new industrial activity;

- the delivery of a new microbial inoculant requires associating technologists (inoculant manufacturing, machinery), soil microbial ecologists (strain selection, strain tracking in soil) and agronomists (efficacy);

Thus, developing the use of microbial inoculants in agriculture and environment requires a combination of scientific expertise and resources from several member states. This proposed COST action will effectively:

- promote an interdisciplinary coordination, resulting in more efficient use of both Community and national funds,

- favour the interests of European manufacturers of high quality inoculants (or create such activity) against competition from foreign low quality products,

- help to define high quality Community standards and give an export advantage to European manufacturers for the trade in inoculants or related processes on the international market,

- develop new processes capable of being adapted to developing countries.

A.3. How the proposed action relates to other international scientific programmes

The proposed action is downstream of the Agriculture and Fisheries Programme, especially action 4.1 Reformed CAP (4.1.1 Optimization of methods, systems and primary production chains and 4.1.2 Agriculture-Environment interactions).

It is related also to the Biotechnology Programme, specially action 7.2 Prenormative research: Biosafety (7.2.2 Biofertilizers, 7.2.3 Biopesticides) to action 7.3 Prenormative research: Biotechnology for the Environment, and to action 7.4 Biodiversity (microbial genetic resources). These research programmes will open new possibilities for microbial inoculant uses and the proposed action will facilitate their transfer to the practical application.

A Eureka Brokerage Event on Biotechnology for the Environment (Brussels, 23-24 November 1995) emphasized the interest for new biofertilizers, biopesticides and other microbial biotechnologies for soil and water bioremediation.

B. OBJECTIVES AND BENEFITS

The main objective of the action is to develop new microbial inoculants and promote their use in agriculture and environment.

This action will associate specialists of different micro-organisms and technologies, from public and private organizations, in order to develop new microbial inoculants and promote their use in agriculture and environment. Four objectives will be achieved:

1) to promote and coordinate research required to develop the use of microbial inoculants in agriculture and environment, in connection with the CAP;

2) to provide know-how for increasing the competitiveness of European research and European inoculant companies at a crucial moment for the development of new management systems in agriculture, using biofertilizers and "biopesticides";

3) to define efficacy criteria able to be checked in a quality control process, in order to raise the quality of European products and make them more competitive on the world market;

4) to provide new bases for guidelines to stimulate the use of microbial inoculants in place (or with) agrochemicals.

C. SCIENTIFIC PROGRAMME

The proposed new action will consider complementary strategies, from the inoculant to its acceptability by users, to develop new inoculants for agriculture and environment and to increase their practical use.

The action will have working groups taking charge of priority topics. The kind of activities proposed within the action will be workshops in order to collect, summarize and publish results of the participants and guidelines.

Additionally, we expect to propose and realize common research programmes (AIR, EUREKA) and exchange researchers between laboratories.

C.1. Inoculant technology

Practical efficacy of an inoculation process is dependent on the potential efficacy of the inoculant (the right number of active micro-organisms at the time of use). In order to increase or stabilize this potential efficacy several factors will be considered for the different types of micro-organisms involved in the action, biofertilizers and "biopesticides":

- strain selection methods, assessment of strain stability in inoculants and strain identification,

- inoculation rate effect and appraisal of recommended inoculation rates,

- optimization of cells production and storage,

- physiological characteristics related to shelf life and efficacy, criteria for quality control,

- second generation inoculants (combining complementary micro-organisms).

C.2. Methods of inoculation

To be efficient, a method of inoculation must deliver the inoculant in the right place with a minimal loss of micro-organisms. Methods used remain tedious, time consuming and produce important losses of inoculant (losses of 90% or more in less than one hour after inoculation for rhizobial inoculants were reported). It is proposed to reconsider the method of inoculation on the following points:

- assessment of the inoculant losses during inoculation and possible corrective techniques,

- new technologies to improve inoculant survival during inoculation and competitiveness against soil microflora,

- new delivery methods and equipment, including methods for granular and liquid inoculants,

C.3. Behaviour of the inoculated micro-organisms after their release in the field

The behaviour of the released micro-organisms must be considered immediately, as their survival can modify inoculation efficacy, and for larger periods, as their characteristics and efficiency may change with time.

They may also modify the soil microflora and change the biological fertility of soil. Until now, most of the research programmes were devoted to GEM (Genetically Engineered Micro-organisms), and more data are required for usual inoculants. The following questions will be considered:

- methodology of inoculant tracking in the field and in model laboratory experiments,

- how to improve inoculant survival, its multiplication in soil after inoculation and the colonization of the target,

- how to monitor the efficacy stability of the introduced micro-organisms,

- assessment of the need to reinoculate,

- methodology of risk assessment for the soil microflora, proposals for registration.

C.4. Acceptability by users

A greater acceptability of such new products may be expected, due to both increased dependability of performance (making it economically viable for growers to replace reliable pesticides and fertilizers), and alleviation of general concern over unwitting contamination of the environment with potentially harmful microbes.

Farmers will use inoculants only if they are compatible with existing agricultural practices and easy to use.

The following points will be considered:

- compatibility with existing agricultural practices (other seed disinfectants, pesticides and fertilizers, possible use of available machinery),

- cost-benefits balance,

- quality control methods and efficacy reliability,

- guidelines for the use of new inoculants in agriculture.

D. ORGANIZATION AND TIMETABLE

Annual meetings on specific subjects are programmed in the following provisional sequence:

1997: Limitations in the production of inoculants: optimization of cell production and storage, physiological characteristics related to shelf life and efficacy, methodology for the study of strain and inoculant stability.

1998: Improvement of inoculation methods: methods and formulations decreasing inoculant losses and increasing efficacy, compatibility with seed disinfection and other crop treatments, appraisal of recommended inoculation rates.

1999: Possible consequences of the release of inoculant micro-organisms into soil: methods to favour or not, the survival and multiplication of the inoculant into the soil, methodology for tracking, stability and side-effects assessment, proposals for registration.

2000: Quality control procedures and benefits assessments: quality control (QC) procedures and new QC criteria, inoculation rates and cost-benefits assessment, stability assessment.

2001: Final meeting and proposals to develop the use of microbial inoculants in agriculture: critical analysis of results, technical guidelines and registration proposals for microbial inoculants.

Four Working Groups (WG) will be organized transversally on priority topics recognized by the Management Committee and covering the main problems associated with: (1) inoculants, (2) method of inoculation and acceptability by users, (3) behaviour of released micro-organisms and possible side-effects and (4) efficacy and reliability of microbial inoculants and inoculations. Programmes and coordinators of these working groups will be designated by the Management Committee. The WG will meet regularly, generally twice a year, including a joint meeting for the annual evaluation meeting (see Time Table), to coordinate and promote research activities and to prepare reviews or surveys on the state of the art. The Action will be ended with a final meeting (FM).

Annual evaluation meetings will be held with the participation of non-European-experts and officials from CEC:

- to review the results achieved and finalize publications,

- to evaluate critically progress achieved in practical applications,

- to promote cooperation within the participating institutes.

Results of annual meetings and/or workshops will be published as a state of the art on specific topics, including the contributions of the COST action participants.

A final meeting will be held in 2001 for evaluating the achievement of this COST action. International experts from outside Europe will be asked to participate and provide a critical analysis of the achievements.

The total duration of the action is estimated at 5 years.

E. ECONOMIC DIMENSION

The following COST countries have actively participated in the preparation of the action or otherwise indicated their interest:

Belgium, Czech Republic, Denmark, France, Germany, Hungary, Netherlands, Spain, Sweden, United Kingdom.

We estimated the number of scientists potentially interested in participating in the action to be 60 for 7 countries (B,D,DK,E,F,NL,UK). Thus after contacting all the countries interested, it can be expected that approximately 70 man-years scientific staff and 70 man-years technical staff will be involved.

The following estimates are valid under the assumption that all the countries mentioned above but no other countries will participate in the action. Any departure from this will change the total cost accordingly.

Staff costs

70 man-years scientific staff ECU 3,5 million
70 man-years technical staff ECU 2,8 million

Total staff cost ECU 6,3 million/year

Laboratory equipment and consumables ECU 2,2 million
Overhead costs ECU 1,1 million

Total estimated costs ECU 9,6 million/year
(covered from national sources)

Coordination costs for the first year ECU 80 000

Total estimated costs of the Cost Action ECU 48 million.

Call for proposal

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Funding Scheme

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Coordinator

N/A
EU contribution
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Address


France

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