The Asian citrus psyllid, Diaphorina citri: ‘Inseccide Resistance Management’ is the Basis of a Successful IPM Program Inseccide Resistance Acon Commiee www.irac-online.org Introducon and Biology Resistance to Inseccides Management Plan Example, US-related The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Fig. 1a.), Various levels of inseccide suscepbility have been reported in Figure 2: Management plan example derived from USA-FL and opportunies for MoA rotaon used for citrus psyllid based on plant phenology. The rotaon uses various MoA is the insect vector associated with the bacteria Candidatus Florida, USA (Table 1). Although the resistance raos are not high which are registered and labeled for control of citrus psyllids. The rotaons and number of Liberobacter asiacus and C. L. americanus. These bacteria are in comparison to those of other pests, it is important to be vigilant MoA might vary according to the number of products registered in each country. suspected to be the causal agents of Huanglongbing (HLB) in Asia to prevent the onset of resistance for this pest. The results in table Growing Pre-bloom/Dormant and America. Trees infected with the bacterial pathogen begin to 1 are correlated with elevated levels of detoxifying enzymes in both ± Adults + Nymphs ± Adults show symptoms such as early fruit drop and moled leaves adults and nymphs collected in the field. However, ACP carrying ü Selecve MoA MoA 2B ü Broad spectrum MoA anywhere from 5 months to 3 years aer infecon. Even during this HLB were shown to be more sensive to inseccides than non- ü Use thresholds MoA 15 ü Area wide asymptomac period, plants can also be source of inoculum, hence infected psyllids. In Brazil, no tolerance has been reported ü Protect natural enemies MoA 1 A/B the need to manage the vector even if the trees are not showing symptoms (Fig. 1b). Once the trees are infected, their producon Table 1: Highest Resistance Rao 50 (RR50) values observed on various wild populaon of D. rapidly declines rendering the infected trees unproducve in a few citri in Florida in 2010. (Tiwari et al. 2011) years. MoA 15

imidacloprid chlorpyrifos thiamethoxam malathion carbaryl spinetoram MoA 28 MoA 28

RR50 adults 35X 18X 15X 5X 3X 2X Harvest Bloom RR50 nymphs 4X 3X No tested No tested 3X 6X ± Adults + Nymphs ±Adults + Nymphs

ü Selecve MoA ü Selecve MoA ü Short PHI and REI ü Bees present ü Protect natural enemies ü Augmentaon of Integrated ACP Management ü Applicaon based on thresholds natural enemies Guidelines Table2: Modes of acon registered for ACP management. Pest and Resistance management should be based on an appropriate rotaon of these MoA

Picture: HA Arevalo. U of Florida Ø Protect nursery plants under neng and use only stock that is Diaphorina citri Adult and nymphs Modes of acon registered for ACP management (NR: Horcultural oils) Picture : ME Rogers U. of Florida cerfied as HLB-free. 1 A&B: AChE 7C: Juvenile hormone 21A: Mitochondrial complex 1 Fig. 1: (a.) Adult of D. citri feeding on a young orange leave. (b.) HLB-infected 4: nAChR agonist Ø Transport infected nursery stock according to government Inhibitors analogues electron transport inhib. trees: asymptomac (le) and symptomac (right). Noce fruits on the ground, leaf coloraon, and dieback are more prominent on the symptomac plant. regulaons. 2B: GABA 5: nAChR allosteric 15: Inhibitors of chin 23: Inhibitor of aCoA antagonists acvators biosynthesis type 0 carboxylase Ø Protect young and non-bearing trees with rotaon of soil Citrus psyllids lay their eggs on the inner-side of unfolding leaves 3: Sodium Channel 6: Chloride channel 18: Ecdysone receptor 28: Ryanodine receptor applied systemic inseccides (MoA 4 and MoA 28). In older modulator acvator agonist modulators which protect the eggs and early nymphs from adequate trees, soil applied systemic inseccides may not work. inseccide contact, rendering applicaons of non-systemic Ø Rotate soil-applied inseccides with foliar sprays of other inseccides inefficient to manage nymphs. Psyllids develop modes of acon. Rotaon of different modes of acon is key Relevant Literature through 5 nymphal instars, taking between 15 and 47 days to to resistance management. become adults, depending on environmental condions. Nymphs Poltronieri, A.S. 2013. Bases para o manejo da resistência de Diaphorina citri (Hemiptera: Liviidae) ao Ø Management of adults during dormant season is key to insecida neoniconoide imidacloprid em pomares de citros. PhD thesis. Escola Superior de acquire the bacteria, and the adults vector the disease to maintain low populaons for the rest of the year. Agricultura Luiz de Queiroz. Universidade de São Paulo. uninfected plants and to plants that are already infected. Re- hp://www.teses.usp.br/teses/disponiveis/11/11146/tde-16052013-162931/pt-br.php Ø Use locally defined monitoring methods and intervenon Rogers, M.E., P.A. Stansly, L.L. Stelinski. 2012. 2012 Florida Citrus Pest Management Guide: Asian Citrus infestaon increases the bacterial ter in already diseased plants. thresholds to make spray decisions. Nofy manufacturers of Psyllid and Citrus Leaf Miner . IFAS –University of Florida . ENY-734 . hp://edis.ifas.ufl.edu/in686 Adults are considered to be the preferred target for foliar any product performance failures immediately. *Tiwari, S., R.S. Mann, M.E. Rogers, L.L. Stelinski. 2011. Inseccide Resistance in Field Populaons of Asian inseccide applicaons since they vector the bacteria. Systemic Citrus Psillid in Florida. Pest Management Science 67: 1258-1268 Ø Use and protecon of bio-control agents is encouraged as part Vanaclocha. P., H. A. Arevalo, A.B. Fraulo, G. Snyder, and P. A. Stansly. 2011. Citrus Greening soil inseccide target nymphs and adults for the first 2 years aer Bibliographical Database. University of Florida. of the IPM programs and to reduce the risk of inseccide hp://swfrec.ifas.ufl.edu/programs/entomology/hlb_db.php planng, aer that period, trees are too big for the current resistance development. chemistries to be effecve. * Provisional method used by IRAC to evaluate inseccide suscepbility by Asian citrus psyllid

This poster is for educaonal purposes only. Details are accurate to the best of our knowledge but IRAC and its member companies cannot accept responsibility IRAC document protected by © Copyright. Designed & produced by IRAC Sucking Pest Team, March 2016, Poster for how this informaon is used or interpreted. Advice should always be sought from local experts or advisors and health and safety recommendaons followed. Ver. 3.3. Photographs courtesy of M.E. Rogers (University of Florida), H.A. Arevalo (University of Florida)