Financial impact of psyllid
Associated Citrus Packers, Yuma, Ariz., has also been impacted financially by the psyllid quarantine.
The family-owned business is the second largest citrus packer in Arizona. The C.V. Spencer family also grows about 1,500 acres of citrus, mostly lemons, on the Yuma Mesa. Ironically, the company shares the same “ACP” acronym as the psyllid.
Notably, the sixth and seventh psyllid finds in Yuma County were in a single Associated Citrus lemon grove, the only commercial Arizona citrus operation where the insect has been found. The other finds were in residential neighborhoods.
ACP shipped about 1 million cartons of citrus during the 2009-2010 season; about 25 percent to 30 percent for export, including to Australia.
Mark Spencer, a partner in Associated Citrus Packers, said, “For the Australian market we’ve had to implement a new protocol at our packinghouse where the USDA inspector examines fruit from each packed lot so they (Australian buyers) could get double assurance that the psyllid could not end up in Australia.”
Another increased cost to the company is an extra required step for citrus not suitable for the fresh market, scarred fruit for example, which is sent to byproduct plants mostly in California to make oil concentrate. Until this year, some of this fruit was shipped directly from the orchards to the byproduct plants.
“Now we have to bring the citrus from the field into our packinghouse to eliminate any leaves and stems before the citrus is shipped to the byproduct plants,” Spencer said.
The extra step cost the company about $30,000 this past season.
McGrew discussed the ACP, HLB and the quarantine during the 2010 Desert Ag Conference held in Casa Grande, Ariz., in May.
Adult psyllids are 3-4 millimeters long and feed at a 45-degree angle. Eggs and nymphs are found on new tree growth. Once the psyllid is infected, the HLB pathogen is found in the hemolymph and salivary glands. The adult lifespan is one to two months.
Positive identification of HLB is conducted through a DNA-based polymerase chain reaction (PCR) analysis. No HLB-resistant citrus cultivar is available, but research is underway.
McGrew says internal tree symptoms of HLB include phloem plugging, the blocked transport of sugar, starch accumulation, and the loss of the internal structure of chloroplasts which results in yellowed leaves.
HLB-infected trees can have poorly developed root systems. New root growth can be suppressed.
Crop hosts for the psyllid include all citrus varieties including hybrids and some citrus relatives in the Rutaceae family.