White Grubs and Other Bad Blueberry Bugs Dr. Sridhar Polavarapu Blueberry and Cranberry Research and Extension Center Rutgers University Chatsworth, NJ 08019

In This Presentation …. Seasonal lifehistory and management of above ground pests Pests feeding on roots

Seasonal Lifehistory and Management of Major Pests Pests that occur during the dormant stage Pre-bloom leaf and flower feeders Bloom-time insect pests Post-bloom pests on foliage and fruit

Pests During Dormant Stage Putnam scale is the main concern Problem in under-pruned fields Superior oil (70-second 3 gal/ac Lime 5 gal/ac Apply on warm days (>50 F) before flower buds begin to open

Pre-bloom Leaf and Flower-Feeders Cranberry weevil, leafrollers, and spanworms are the major pests ET of one larvae per 100 clusters for caterpillars For CW, treat if >5 weevils per bush or 20% injured flower clusters

Bloom-time Insect Pests Gypsymoth larvae, leafrollers, and aphids are the main concern Bts and Confirm 2F are the insecticide options Same threshold as pre-bloom No aphid controls during bloom

Post-bloom Pests on Foliage and Fruit Cranberry fruitworm, plum curculio, blueberry aphids, and blueberry maggot are the major pests Leafminers, and leafrollers are occassional problems Most insecticide applications are made during this phase

Post-bloom Pests on Foliage and Fruit Cranberry fruitworm Single generation per year Pheromone traps are used for monitoring Single insecticide application 5-7 days after the peak Typical timing June 1-5

Confirm 6/1&6/8 Diazinon 6/1&6/8 Confirm 5/25&6/1 Confirm 6/1 Control Larvae per 100 Clusters % Damaged Clusters Effect of timing of Confirm 2F applications on efficacy against CranberryFruitworm a a b a b b b bb bb CFW 2000

Post-bloom Pests on Foliage and Fruit Blueberry aphids A complex of several species Vectors of blueberry scorch and other viruses Species identified in NJ blueberries Illinoia azaleae Ericaphis spp. Macrosiphum euphorbiae, M. rosae Aphis spiraecola, A. gossypii Myzus persicae

Post-bloom Pests on Foliage and Fruit Constraints in Managing Blueberry Aphids Natural enemies Low tolerance because of vector status Use of broadspectrum insecticides leading to natural enemy destruction Poor coverage

Evaluation of Imidacloprid Applied as Soil Drench Against Blueberry Aphids Imidacloprid treatments at 0.25 and 0.5 lb A.I./acre were evaluated as soil drench Four replications, 3 bushes per replication Insecticide was applied in 1000 mL per bush on June 7 Aphids were sampled on June 14 and 21

Control Imidacloprid 0.25 lb.ai/ac Imidacloprid 0.5 lb.ai/ac Total Aphids Pre-spray 6/7 1st Post-spray 6/14 2nd Post-spray 6/21 Evaluation of imidacloprid applied as soil drench % IT a a a a a a a ab b a b b a a a a b b

Evaluation of Foliar Applications Imidacloprid, Thiamethoxam, and Thiacloprid were evaluated Four replications, four bushes per replication in a single row R&D sprayer, 30 gal/acre, Conejet 4VS hollowcone nozzle Insecticides were applied twice on June 6 and 13 and aphids sampled on June 6, 12, and 21

Evaluation of foliar application of insecticides % IT Total Aphids Pre-Spray, 6/6 Post-Spray, 6/12 Post-Spray, 6/21 ControlCalypso 480 SC 1.5 fl.oz/ac Calypso 480 SC 3.0 fl.oz/ac Provado 1.6 F 3.0 fl.oz/ac Actara 25 WDG 85.2g/ac a b bc c c a b c c a b c c a b c c a aa a a a abc bc c ab

Post-bloom Pests on Foliage and Fruit Blueberry maggot Overwinters in the pupal stage Adults emerge beginning June 10 Females need 10 days to become reproductively mature Calendar sprays begin 10 days after adult emergence

Blueberry Maggot Management Quarantine pest Wide-window of emergence and oviposition Presence of wild and voluntary sources of infestation Research focus on monitoring and timing of insecticide applications

Blueberry Maggot Export Regulations CFIA promulgated new regulations in 1999 To qualify for export, grower must participate in a BM Certification Program Growers are required to follow either a calendar-based or IPM-based approach for BM management Major constraint in IPM adoption

Red Sphere Green Sphere Pherocon AM trap Currently recommended for monitoring Blueberry Maggot Population Monitoring Yellow boards - hue - reflectance Spheres - shape - intensity contrast with background

Insecticide-treated Spheres for Blueberry Maggot Control Ammonium acetate/carbonate Color Shape Fruit volatiles Sugar Proteins

Root-feeding Pests - Oriental Beetle

White Grub Rastral Patterns Asiatic Garden Beetle Oriental Beetle May-June Beetle

Evaluation of Imidacloprid and Insecticidal Nematodes Against Oriental Beetle

Imidacloprid for Scarab Grub Management Applied as a 40cm-wide band on each side of the bush Works best against 1st instar larvae Apply in early June to mid-July Irrigate before and after application Apply in the evening hours Current blueberry registration allows only a maximum of 0.3 lb AI/acre/year for grub control The other 0.2 lb AI/acre/year is used for foliar control of aphids

S new 3.0 S new 1.5 S new 0.75 Hb 3.0 Hb 1.5 Imid Imid Imid 1.5 Thia. 0.6 Imid new-S 0.75 Control Treatment Greenhouse Evaluation of Insecticidal Nematodes and Chloronicotinyls # of Grubs

Root-feeding Insects Blueberry Mealybug Ant-mealybug relationship Disrupt this relationship for control

Any Questions ?