2019 ASHS Annual Conference

Since the first finding of the Asian citrus psyllid (ACP; Diaphorina citri Kuwayama) in 2001 and detection of Huanglongbing (HLB; citrus greening disease) in 2012, Texas has raced to control HLB spread and impact on the citrus industry. A proactive psyllid area-wide management programs have been implemented to reduce ACP populations with significant success. Additional HLB mitigations efforts included the removal of confirmed HLB-positive trees, the production of nursery trees in insect-resistant structures and the phase out of open-field nurseries, and the enactment of quarantines that restrict intra-state movement of plants. Altogether, these strategies have slowed the spread of HLB, but to date the prevalence of HLB is around 40% (2018). Citrus groves in Texas are not yet showing the rate of decline due to HLB that has been recorded in Florida. Some trees that were diagnosed in 2012 are still productive and have maintained yield with minimal dieback, although this is not the case throughout the Lower Rio Grande Valley region. In certain groves there are severe declines in production, distinctive symptomology, and significant dieback, while in others trees exhibit few symptoms and are maintaining if not increasing yield. A historical analysis of Texas citrus acreage and production value per acre we found that not only is citrus acreage increasing but the production value per acre has increased greatly, exceeding Florida production value per acre in 2016. In fact, 2018 Texas citrus production value was 29% of the US total citrus production value compared to California at 36% and Florida at 35%. This shows that while HLB is spreading throughout Texas, the impact is not yet as anticipated, likely because of the control measures put in place and/or the environment. While we are optimistic of our overall outlook regarding HLB, we remain cautious and are invested in proactive measures to control and prevent HLB in new orchards.