1a.Objectives (from AD-416)
The objectives of this cooperative research project are to assess irrigation method (scheduling) and substrate composition on plant growth and physiology, on water and nutrient use efficiency, and on substrate physical and chemical properties for selected containerized nursery crops.
1b.Approach (from AD-416)
Record effluent volume and calculate water use efficiency, determine plant tissue and substrate N and P, and photosynthetic rate and stomatal conductance for selected containerized nursery crops under various irrigation schedules (volume and timing) and substrate compositions (percent clay).
The relationship of the project to both objectives of the in-house project include the development of integrated horticultural production systems, in this case the use of calcined clays to improve the water holding capacity and phosphorous retention of amended substrates. Monitoring activities by the Authorized Departmental Officer's Designated Representative (ADODR) over the project included communications by phone and by electronic means, and a face-to-face meeting in May 2008 and at scientific meetings in July and August, 2008. Briefly, calcined clay amended substrates significantly improved pine-bark nursery substrate water holding capacity, reduce phosphorous leaching, reduce substrate bulk density, and improve plant growth.