Phenology models predict timing of events in an organism's development. For many organisms which cannot internally regulate their own temperature, development is dependent on temperatures to which they are exposed in the environment.
Information in this database comes from published articles. It may be used in conjunction with field monitoring and a degree-day calculator.
Note: Before using a model that was not field tested in your location, you should test the model for one or more seasons under your conditions to verify that it will work for you.
Model 1
Kieckhefer, R. W., and N. C. Elliott. 1989. Effect of fluctuating temperature on development of immature Russian wheat aphid (Homoptera: Aphididae) and demographic statistics. J. Econ. Entomol. 82: 119-122.
- Location of study: South Dakota (laboratory studies)
- Lower developmental threshold: 39.4°F (4.1°C)
- Upper developmental threshold: 90.7°F (32.6°C)
- Method of calculation: Max-min (UC IPM recommends Single Sine)
- Cutoff method: Horizontal
Degree-day accumulations required for each stage of development
Host: Spring Wheat
- Apterae birth to reproduction: 250.0 (°F) 139.0 (°C)
- Alatae birth to reproduction: 284.0 (°F) 158.0 (°C)
Model 2
Girma, M., G. Wilde, J. C. Reese. 1990. Influence of temperature and plant growth stage on development, reproduction, life span, and intrinsic rate of increase of the Russian wheat aphid (Homoptera: Aphididae). Environ. Entomol. 19: 1438-1442.
- Location of study: Kansas (laboratory studies)
- Lower developmental threshold: 29.17°F (-1.57°C)
- Upper developmental threshold: 52.20°F (29.00°C)
- Method of calculation: not specified (UC IPM recommends Single Sine)
- Cutoff method: not specified (UC IPM recommends Horizontal)
Degree-day accumulations required for each stage of development
Host: Winter Wheat
- Preimaginal development: 406.02 (°F) 225.57 (°C)
