Biotic stress is stress that occurs as a result of damage done to plants by other living organisms, such as bacteria, viruses, fungi, parasites, beneficial and harmful insects, weeds, and cultivated or native plants.
It is a major focus of agricultural research, due to the vast economic losses caused by biotic stress to cash crops. The relationship between biotic stress and plant yield affects economic decisions as well as practical development. The impact of biotic injury on crop yield impacts population dynamics, plant-stressor coevolution, and ecosystem nutrient cycling. Biotic stress also impacts horticultural plant health and natural habitats ecology.
Biological pest control
Biological pest control herbivore agents feeding on invasive species results in biotic stress, part of reducing and controlling some noxious weeds in agricultural areas and natural ecosystems. The use of mottled water hyacinth weevil (‘’Neochetina eichhorniae’’) worldwide on water hyacinth (Eichhornia crassipes) is an example.   More dominant cultivated or native plants in biological weed control can cause biotic stress from root, water, or nutrient competition below the surface, or from shading of sunlight above. This method can be part of habitat restoration projects.
- Robert K.D. Peterson, Leon G. Higley. "Biotic Stress and Yield Loss." 2001.
- U.S. Army Engineer Research and Development Center, Waterways Experiment Station: Neochetina eichhorniae - "Mottled Waterhyacinth Weevil" . accessed 1.11.2011
- Australian Museum: Waterhyacinth Weevil, Neochetina eichhorniae . accessed 1.11.2011