Bayer CropScience and Mendel Biotechnology, Inc. in Hayward, California, have entered into a new three-year collaboration agreement which extends their existing joint activities.

The objective is to develop chemical products which make crops more resistant to biotic and abiotic stress factors, which in turn will stabilise yields and improve crop productivity.

Bayer CropScience is contributing its expertise in chemical research - specifically in substance screening - to this collaboration. The company is already marketing products which enhance the stress tolerance of plants and boost yields under the ''Stress Shield Inside'' label. Mendel, a pioneer in plant functional genomics, has a large number of biotechnology patents. Mendel researchers have identified key genes responsible for controlling plant growth and environmental responses and are applying these discoveries to improve plant performance.

The research programme focuses on new approaches to improving crop productivity. The aim is to develop substances which chemically modulate the signalling networks used by plants to control parameters such as growth and stress tolerance. Mendel and Bayer have already worked together for several years in the discovery and development of chemical products to regulate plant stress tolerance. This partnership will now be extended to include the discovery of substances which regulate additional components of crop yield potential.

''Chemical products that mediate enhanced crop performance are an untapped market with potentially high added value,'' commented Dr. Alexander Klausener, Head of Research at Bayer CropScience. ''New solutions would enable Bayer CropScience to make a significant contribution to safeguarding agricultural yields and increasing productivity in the longer term. Although abiotic stress factors cause substantial loss of yields in agriculture, the development of products to strengthen plants and increase yields is a largely uncharted field of research.''

Oliver J. Ratcliffe, Mendel's Vice President of Research said, ''This new programme now provides the opportunity to expand our chemical research into additional valuable areas. The partnership offers significant synergies and leverages both Mendel's knowledge and advanced technology platforms for analysis of gene regulation as well as the expertise of Bayer CropScience."

Bayer CropScience, a subsidiary of Bayer AG, is a leading innovative crop science companies in the areas of crop protection, non-agricultural pest control, seeds and traits, represented in more than 120 countries.

Mendel Biotechnology, Inc. is a leader in the application of functional genomics to the study of plant genes. Mendel has identified genes that control many aspects of plant growth and development, and is working to develop or co-develop new plant varieties with improved productivity and quality.