We continued our tree evaluations at the three trial locations (1) SWFREC, (2) Hendry County – Duda & Sons, and (3) Polk County – Peace River Packing Co. during the third quarter of 2019. Tree evaluations included monthly (SWFREC) or bimonthly (Hendry County and Polk County) root growth measurements using rhizotrons and leaf flush ratings. In addition to rhizotron measurements, root cores were collected at each location to determine root densities and other fibrous root properties. Leaves were collected from all trials for nutrient analysis. Statistical data analysis is still in progress.
Two-year tree growth data are currently being collected for trees located at SWFREC, and preparations at SWFREC are in progress for whole tree excavation and detailed root architectural analysis, plant biomass determination, hydraulic conductivity measurements, and measurement of other tree parameters.
Updates on project progress were presented during the Citrus Expo seminar presentation in August (“Bigger is not always better – large-scale rootstock evaluations on a Ridge and flatwoods site”) and poster display “Rootstock propagation methods” with printed educational material. Additional information was presented during a seminar at SWFREC in September titled “Which rootstock to plant in an HLB-endemic environment”. A new EDIS publication “Citrus nursery production guide, chapter 6: Citrus rootstock propagation: traditional techniques and recent advances” was completed and is available at https://edis.ifas.ufl.edu/hs1329.
We are awaiting to plant the fourth trial at a site in Indian River County (FLARES Inc.) once the grower has finalized his decision on the grove location. Trees are field-ready and in the holding stage at the USDA Horticultural Research Laboratory DPI-certified greenhouses in Ft. Pierce.