2008-09 Deliverables
Task 5 Research
Principal Investigator(s): Raul Cabrera
- Continue characterization of short (hourly, daily) and long-term (seasonal) patterns of water and nutrient uptake in rose crops. Results from the existing experimental hydroponic system will be used to evaluate various irrigation/fertilization schemes under standard production conditions (both in experimental and in commercial greenhouses).
- Evaluate the water and nutrient use of three Texas native street trees (Ulmus crassifolia, Celtis laevigata and Maclura pomifera) infested by the parasitic xylem-tapping leafy mistletoe (Phoradendron spp.). We will monitor water and nutrient use by mistletoes in mature infected trees growing under a range of landscape management conditions (none to highly-managed). This includes physiological determinations of water relations and nutrient status (stomatal conductance, water potential, chlorophyll, tissue nutrient concentrations) in both the mistletoe and its hosts through the seasons. Secondly, we will attempt to manually infect container-grown cedar elms (Ulmus crassifolia) to subsequently measure, by mass-balance approaches, water and nitrogen fertilizer use by the whole plants in comparison to non-infected (control) plants, both under stressful and optimal management conditions