Research progress Sept 2022-December 20221. Near term field management(a) Develop methods to time management actionsIn the previous report, I discussed our efforts to understand the odors that appear to be attracting lebbeck mealybug to help develop better scouting and potentially an odorant lure in the future to make sampling to determine management easier. To date, the primary components of the tree parts as well as damage have been identified and pure isolates of these odors have been obtained. We are currently testing attraction to combinations of these odors and to individual odors to move closer to understanding what the mealybugs are attracted to. Because there is a strong recruitment of lebbeck mealybug to our traps around small wounds versus traps without wounds (Fig. 1), we anticipate that the odors associated with this damage will be the most attractive.(c) Evaluate promising materials in open grove settingIn the fall of 2022, we completed 2 field trials to look at longevity of several promising foliar applied insecticides. The first trial compared those known to have contact activity. We tested Agri-Flex (8.5 oz/a), Transform (2.75 oz/a), Voliam-Flexi (7 oz/a), Besiege (12.5 fl oz/a), AgriMek (4.25 fl oz/a), Actara (5.5 oz/a), Minecto Pro (12.5 fl oz/a), and Esteem (5 oz/a) (all with 0.25% NIS). Materials were applied to trees with flush in the grove and leaves that were soft but fully expanded brought back to the lab where they were challenged with mealybugs. In week 1, Agri-Flex had the greatest mortality with over 80% of juvenile mealybugs dying, closely followed by Transform (68%), and Voliam-Flexi (31.5%). All other chemistries were no different than the untreated control for mortality in the first week of application. Unfortunately there was no residual efficacy for any materials in weeks 1, 2, and 3 after application. In the second trial, we focused on foliar-applied insecticides with systemic activity and included some variation in rate as well as adjuvant used. Treatments consisted of: Movento 16 oz/a + NIS, Senstar + NIS, Sivanto + NIS, Movento 10oz/a + 435 oil, Senstar + 435 oil, and control. In the initial week of application, Movento + NIS had the highest mortality at 38%, Senstar +NIS, Sivanto + NIS both had 28% mortality, and the rest fell below this. This isn’t surprising as systemic materials need time to build up in leaves and most mortality was likely due to the adjuvant sticking to the insects and smothering them. One week after application, the Movento 10 oz + oil had increased mortality relative to the other treatments (37%) but no material showed the ability to kill 50% or greater of the nymphs at any point in the trial. This is not consistent with what we see in CUPS houses when these systemic materials have been applied. I believe the reason for this is that the trees we were testing have had HLB for several years and materials are not likely moving through the vascular system as they would in a health tree. In healthy trees, systemic materials are able to translocate through the canopy, and it is likely that the vascular plugging exhibited by HLB affected trees reduces this.II. Long term managementc. Determine what insecticide chemistries inhibit feedingWhile there has been some progress on this subobjective, it has been far slower than anticipated. Weve sent equipment for repair/ tune- up and are reworking the initial feeding interaction data.Working with the repaired equipment, we have been able to document the feeding waveforms, though with some noise, that we will need to move forward and complete documenting the feeding interactions. We can now see the E1/E2 ingestion pathway (Fig. 3). This must be fully documented and reviewed to move into the next step, which will be determining if we can interrupt the feeding via insecticides and at what rate we need to interrupt feeding, halt offspring production, and lead to adult mortality.d. Develop tools to minimize spreadWhile we were unable to complete the solarization and freezing studies we had planned this past term due to colony infestation by a predator impacting available insects to work with. However, we did make progress in understanding lebbeck mealybug dispersal, which is important for determining broader methods for reducing spread. In the late summer of 2022, we built a wind tunnel in which we can control the velocity of wind (Fig 3). In this wind tunnel, we can introduce plants from below with varying states of infestation and at varying distances. While still preliminary, we are finding lebbeck mealybug fairly easy to dislodge at low to medium wind velocities (Fig. 4). 10 minutes at a high velocity of wind (exact speed will be reported later, the anemometer is broken) is sufficient to dislodge 50% of crawlers, 30% of immatures, and 15% of adult females. The ability to dislodge easily in wind events helps to understand the rapid spread of this pest and underscores the important of management actions shortly after major weather events.II. Next quarter:We are continuing to test promising materials in open groves and are in the process of planning a test of a subset of materials in a CUPS house as we have learned that chemistries dont all behave similarly in CUPS to the open field.We will continue to document feeding interactions and plan to start insecticide trials in late spring to document influence of systemic chemistries on feeding, offspring production, and mortality.We will continue working towards identifying appropriate odors to use towards future scouting tools.Solarization and freezing tests for sanitation will be completed in spring 2023.III. Budget statusWe are behind on salary spending after having a vacant postdoc position for several months, however we are on track in other categories.