Use of natural enemies to keep pest populations low Predators Parasitoids Pathogens
Predators Pests Squash Bug Squash bug lay eggs on plant leaves/stems Stink Bugs Cucumber beetles lay eggs at base of stem and soil near plant Striped Cucumber Beetle Ground Beetles Eggs likely fed upon by generalist predators Do predators provide significant biological Ants Spotted Cucumber Beetle control of pest eggs? Lady Beetles
Pumpkin Pests – Biological Control of Eggs• Spotted CB and Squash Bug eggs studied Spotted cucumber• Live sterile colony eggs beetle eggs on ground glued to cards – OPEN/CLOSED treatments (4 reps) – In the field for 48 hrs Squash bug eggs attached to plant – July-August leaves
Pumpkin Pests – Biological Control of Eggs Predators reduced squash bug Squash bug eggs by 10% and spotted eggs eaten by predator cucumber beetle by 80%!!
Feather-legged Fly Pests (parasitoid of squash bug)Pest adults are attacked Squash Bugby parasitoid fliesTachinidaeDo we detect significantparasitism of pests in thefield?Celatoria diabroticae and C. setosa Striped Cucumber Beetle(parasitoids of cucumber beetles) Spotted Cucumber Beetle
Pumpkin Pests – Biological Control of Adults • Assessment of adult parasitism • 2 collections of striped cucumber beetle and squash bug from each site, July – August • Raised for 8 days, then frozen & dissected Celatoria sp larval mouthparts
Pumpkin Pests – Biological Control of Adults • 10-17% of adult pests were parasitized! • Does not account for number which may have been killed by parasitoids and not captured
Integrated Pest Management (IPM) is the combined use of tactics tomanage a pest (insect, disease, or weed) in an economically andecological sound manner. Biological control is an Physical Physical Control Control important and sometimes undervalued component of IPM Integrated Cultural Cultural Biological Biological Control Control Pest Control Control Diverse group of arthropods Management contribute to biological control Chemical Chemical This service is provided free Control Control to growers and can be enhanced through habitat management practices.
Biological Control – Habitat Management How can you modify high tunnel production to provide habitat for natural enemies? What do these beneficial insects need? • Alternative food/prey resources • Shelter/nesting sites In the video we will discuss: Mulching, Tillage Practices, Selective Insecticide Use, Providing Additional Flowering Resources.
The addition of flowers can provide resources in andaround the crop.
Natural enemies and pollinators feed on pollen and nectar from flowersNative Bees Predators Parasitoid Flies
Feeding on pollen and nectar builds up populations, increases longevityand reproductive potential of pollinators and natural enemies Double egg laying and lifespan with access to floral resources (Shahjanan 1968)
Natural enemies feed on alternative prey within flowering plant habitats
Flowering plants provide shelter and nestingsites for pollinatorsPerennial habitats provide overwintering sitesboth below ground & remaining foliage. Bumble bee nesting site Mason bee nests (native pollinator)
Flowering plants provide shelter and nesting sites for natural enemiesPerennial habitats provide overwintering sites both below ground &remaining foliage.Lady beetles overwinter in the soil Mantid egg mass Orb Weaver egg mass
Planting Flowering Plant ResourcesAnnual plant insectariesCommon species used in habitat management include sweetalyssum, coriander, phacelia, dill, and buckwheat.Pros –High pollen and nectar productionResources provided same year as plantedLow seed costsCan be planted in rows within main cropCan be re-established next to crop of choice each seasonCons-Pay to establish each yearOnly one type of plant, may not have long bloom periodDoes not provide overwintering habitat if removed at end of seasonPlants are not native species
Planting Flowering Plant ResourcesPlanting arrangements for annual plant insectaries Strips within the main crop
Planting Flowering Plant ResourcesPlanting arrangements for annual plant insectaries Phacelia hedgerow next to cabbage crop Weedy plants allowed to persist until crop established Buckwheat cover crop
Planting Flowering Plant ResourcesPerennial plant insectariesNearly endless diversity of plant choices. Much research had focusedon the use of native perennials to provide habitat for beneficialinsects.Pros –High pollen and nectar productionCan customize bloom period and species complexProvide overwintering habitatEstablish once, benefit for several yearsIf natives are used enhances biodiversityProvides food, nesting for other wildlife such as ground-nesting birdsCons-Seed costs greater than annualsPlants take 2-3 years to fully establishCannot move planting annually
Top 10 observed natural enemies 2% 1% 1% 1% Ant 4% Long Legged Fly 5% Syrphid Fly 33% Spider15% Green Lacewing (Egg) Parasitoid wasp Crane Fly Dragon Fly 17% Robber Fly 21% Lightning Bug Total number of insects = 1821
Planting Flowering ResourcesInterested in designing an insect habitat?Website: http://nativeplants.msu.eduWhat plants are attractive?Bloom phenologyPest attractive?How to plant and maintain
Next in this session….. NEW Natural Enemies Video developed by GLVWG: • Identification of key natural enemies • Learn which pests key natural enemies attack • Habitat management to enhance natural enemies on-farm • Receive new ID guide to vegetable natural enemies Presentation by Megan Woltz: • How the farm landscape influences natural enemies and biological control