GREENHOUSE BIOCONTROL IN UTAH BENEFICIAL INSECTS AND THE PESTS THEY TARGET GREENHOUSE BIOCONTROL IN UTAH BENEFICIAL INSECTS AND THE PESTS THEY TARGET Author Marion Murray, Utah State University Illustrations and Graphics Alex Loveland, Utah State University Funding Crop Protection and Pest Management Program [grant no. 2017-70006-27147/project accession no. 1013830] from USDA NIFA Western Sustainable Agriculture and Research Professional Development Program Contact Utah State University Extension IPM Program 5305 Old Main Hill Logan, UT 84322 ipm.usu.edu TABLE OF CONTENTS Aphids Pest Information ............................................................ 2 General Parasitoid Information ................................ 6 Aphelinus abdominalis ................................................. 8 Aphidius colemani ......................................................... 10 Aphidius ervi .................................................................... 12 Aphidius matricariae ..................................................... 14 Aphidoletes aphidimyza ............................................... 16 Chrysoperla rufilabris .................................................... 18 Hippodamia convergens .............................................. 20 Fungus Gnats Pest Information ............................................................ 22 Dalotia coriaria ............................................................... 24 Stratiolaelaps scimitus .................................................. 26 Steinernema feltiae ........................................................ 28 Mealybugs Pest Information ............................................................ 30 Anagyrus pseudococci .................................................. 32 Cryptolaemus montrouzieri ......................................... 34 Leptomastix datylopii .................................................... 36 Scales Pest Information ............................................................ 38 Aphytis melinus ............................................................... 40 Lindorus lophanthae ..................................................... 42 Spider Mites Pest Information ............................................................ 44 Amblyseius andersoni ................................................... 48 Feltiella acarisuga ........................................................... 50 Galendromus occidentalis ........................................... 52 Neoseiulus californicus .................................................. 54 Neoseiulus fallacis .......................................................... 56 Phytoseiulus persimilis .................................................. 58 Stethorus punctillum ..................................................... 60 Thrips Pest Information ............................................................ 62 Amblyseius swirskii ......................................................... 64 Neoseiulus (Amblyseius cucumeris) ........................... 66 Orius spp. .......................................................................... 68 Stratiolaelaps scimitus .................................................. 70 Steinernema feltiae ........................................................ 72 Whiteflies Pest Information ............................................................ 74 Amblyseius swirskii ......................................................... 76 Delphastus catalinae ..................................................... 78 Encarsia formosa ............................................................ 80 Eretmocerus eremicus ................................................... 81 Banker Plants and Quality Control ....................... 84 Resources and Image Credits .................................. 89 Insects on a Sticky Trap (not to scale) Monitoring withInsects sticky traps is on important a sticky when using trap biocontrol. The Insects on adrawings sticky below trap depict some insects that may be foundInsects on the traps. on a sticky trap (not to scale) (not to scale) (not to scale) parasitic wasp aphid parasitic wasp parasitic7 mmaphid wasp parasiticaphid6 waspmm (winged) aphid 7 mm 7 6mm mm 7 mm6 mm 6 mm fungusfungus gnat gnat shoreshore y fly fungus gnat shore y fungus gnat shore y 2.52.5 mmmm 2 2mm mm 2.5 mm 2 mm 2.5 mm 2 mm thrip whitey thrip whitey1 mm thrip0.8 mm whitey 1 mm 0.8whitefly mm thrips1 mm (winged) 0.8 mm 1.6 mm 1 mm 1 APHIDS Pest Information Aphids are pear-shaped, soft bodied insects that suck plant sap through a straw-like mouthpart called a stylet. They are found in colonies on the undersides of leaves in association with honeydew (sugary excrement). Characteristic features include two “tail pipes” (cornicles) on the rear of the abdomen, and shedded white exoskeletons. Adults develop wings when populations become crowded, and move to another area to feed. Symptoms Leaf curling, yellowing, distortion, stunting. The sticky honeydew is messy and serves as a substrate for sooty mold fungi. Aphids can vector viral diseases. Monitoring Conduct visual inspections regularly throughout the crop’s APHIDS cycle. Pay attention to the undersides of leaves and new growing points. Yellow sticky cards that trap winged aphids indicate existing colonies. Individual greenhouse operations should set their own thresholds. Biocontrol Options (in order of effectiveness) - Aphidius colemani - Lady beetles (while temperatures are below 90°F) - Green lacewing (while temperatures are above 90°F) - Aphidius ervi - Aphidius abdominalis 2 Green peach aphids have an indentation between the base of their antennae on the front of their head. The cornicles are dark at the extreme tips. APHIDS Winged green peach aphids have an irregular patch on the abdomen. Potato (foxglove) aphids are similar to green peach aphids, but shinier and have longer cornicles. 3 Top: Aphids can be found on the undersides of leaves, congregated around leaf veins. Color of the species may vary depending, on the season. Left: Aphids reproduce through parthenogenesis, meaning that they give birth to live young. APHIDS Melon aphids are small, and their cornicles are short and black. Their color ranges from light yellow to dark green. 4 Identification of Aphids Winged Aphids ThoraxThorax darker darker than than abdomen Thorax green;Thorax no green; abdominal no abdominal dorsal markings; abdomen dorsal markings; large (4 mm) large (4 mm) MacrosiphumMacrosiphum euphorbiaeeuphorbiae potatopotato aphidaphid IrregularIrregular patch patch on on dorsal dorsal abdomen;abdomen; NoNo abdominal abdominal dorsal patch; patch; antennalmedium tubercles to large (≥ swollen; 3mm); abdomensmall light (< to2mm); dark green; mediumantennal to tubercules large (> 3swollen mm) abdomensmall light (< 2to mm) dark green APHIDS Myzus persicae Myzusgreen peach persicae aphid AphisAphis gossypii green peach aphid melon/cottonmelon aphid aphid Wingless Aphids Cornicles short (same as cauda); CorniclesMedium longer to large than (≥ 3 cauda; mm); Small, rounded (2mm); cornicleshead short flattened; (= cauda); antennalcornicles tubercles longer than developed; cauda; small (2head mm), attened rounded body mediumantennal tuberculesto large (> developed 3 mm) AphisAphis gossypii gossypii melonmelon aphid aphid AntennalAppendages tubercules light; swollen; AppleAntennal green tubercules in color; diverging; very mobile; antennalbody tubercles pear shaped; swollen; bodyantennal long (4mm),tubercules apple diverging; green; bodyappendages pear-shaped light bodyvery long mobile (4 mm) Myzus persicae green peach aphid Myzus persicae MacrosiphumMacrosiphum euphorbiae potato aphid green peach aphid potato aphid 5 Parasitoid Wasps General Information Parasitoid wasps require a host to complete their life cycle. Adult females lay a single egg inside an aphid. Once hatched, the wasp larva then feeds on the aphid contents over a period of up to 2 weeks. During this time, the aphid swells and stops feeding, becoming a “mummy.” It may turn tan, brown, or black, depending on the species of wasp or aphid. The larva then pupates inside the aphid, and the adult emerges through a smooth circular hole. The emergence “flap” may or may not remain. General Management Parasitoid wasps can be introduced at low rates before aphids are detected or when aphids typically start appearing. Stop use of broad spectrum pesticides 4 weeks before release. If the aphid population is high, use a low-toxicity insecticide, such as soap or oil, to reduce numbers and make it easier for wasps to find and move among aphids. APHIDS Remove yellow sticky traps (OK to leave blue traps for thrips). Keep greenhouse temperature below 85°F. Monitor weekly for parasitized aphids (mummies) and leave these in the greenhouse. When 80% of aphids are parasitized, the parasitoid and aphid populations are balanced. For aphid infestations, use in combination with Aphidoletes and ladybugs. Effectiveness may be reduced in late summer when the parasitoid wasp itself may be attacked by naturally occurring hyperparasites. These are even smaller wasps that parasitize the biocontrol wasp inside the aphid, and will emerge instead of the biocontrol. Use a 10–15x hand lens to inspect aphid mummies for round holes in the hind end. This indicates the adult parasites have emerged. The emergence of an Aphidius species produces a clean, round hole without jagged edges. A ragged emergence hole, in the top, mid- back of the mummy, indicates a hyperparasite has emerged. 6 Life Cycle of Aphid Parasitoid