2009 Annual Report 1a.Objectives (from AD-416) The objectives of this cooperative research project are to. 1)apply aerial and substrate water measurement and modeling techniques,. 2)schedule nursery water use by integrating interactions between plant growth environment and recent advances in physiological process modeling of nursery water flux and, and. 3)move toward the development of a real-time model-sensor integrated system that calculates plant water use on a genotype specific basis. 1b.Approach (from AD-416) Measure inherent plant physiological responses and calculate physiological parameters. Develop process models for plant water use calculations. Simulate, forecast, and prescribe plant water use on a genotypic basis for selected containerized nursery crops under various irrigation schedules (volume and timing). 3.Progress Report The relationship of the project to the objectives of the in-house project include the development of integrated horticultural production systems, in this case mechanistic models to predict the water use and irrigation requirements of genetically diverse nursery crops. Briefly, parameterization of the physiological response on a genotype basis allows reliable modeling of transpiration, thus circumventing over watering or under watering. Moreover, representing genetic variation in physiological traits through genotype-specific model parameters has resulted in a practical means to improve nursery crop transpiration predictions across varying environments. Monitoring activities by the Authorized Departmental Officer Designated Representative (ADODR) over the project included communications by phone and by electronic means, and a face-to-face meeting at the American Society for Horticultural Science annual meeting in July, 2009 in St Louis, Missouri.