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Research and IPM

Phenology Model Database

Citrus Flower Model

Variety: Washington Navel

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 of 1

Lovatt C.J., Streeter S.M., Minter T.C., O'connell N.V., Flaherty D.L., Freeman M.W., Goodell P.B. (1984) Phenology of flowering in Citrus sinensis [L.] Osbeck, cv. Washington Naval orange. Proceedings of the International Society of Citriculture 1, 186-190.

SEE ALSO: Bellows, T. S., Jr., J. G. Morse and C. J. Lovatt. 1989. Modelling flower development in citrus. IN Wright, C. (Ed.) Manipulation of Fruiting. Butterworths, pp. 115-129 (Chapter 9).

Location of study: Tulare County, California (field studies)

Developmental threshold

Method of calculation: Double Sine

Degree-day accumulations required for each stage of development

Start date: January 29

  DD (°F)DD (°C)
10% anthesis in the southwest quadrant 536.4298.0
75% petal-fall in the northwest quadrant 766.8426.0

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