Preliminary data on water uptake by huanglongbing infected trees
Improved understanding of citrus water use and soil moisture distribution in Huanglongbing (HLB) (Candidatus Liberibacter asiaticus) infected and affected groves is critical for devising appropriate recommendations for optimizing water use and sustaining citrus yields. Thus, a study is being conducted to investigate water use patterns and soil moisture movement in central, south-central and southwest Florida. Treatments being evaluated include: 1) daily irrigation (Daily); 2) Institute of Food and Agricultural Sciences (IFAS) recommended scheduling; and 3) irrigation scheduled half the number of days between irrigation recommended by IFAS (Intermediate). The irrigation amounts of the daily and intermediate irrigation schedule are reduced to provide similar amounts of water to the IFAS recommendation over long periods of time. Preliminary results indicate that water use per unit leaf area ranged from 0.09 to 0.10 oz/inch2/ day at all sites depending on irrigation schedule. Moisture contents were similar among irrigation schedules varying between 5% to 20%, 1% to 14%, and 5% to 25% at 6-, 12-, and 18-inch soil depths, increasing with depth possibly as a result of uptake in the top 12 inches. These preliminary findings should help in refining limits for available water contents and estimating irrigation demand estimations to sustain citrus productivity of HLB infected trees.