Plant - Insect Interactions • Seeing The Universe • From An Insect’s Perspective • T’ai Roulston
The problems faced by animals that eat plant products Get Food Find Mates Avoid Being Eaten
The problems faced by plants Get Pollinated Disperse Seeds Avoid Being Eaten
How Insects Affect Plants Pollination Positive Insect Plant Negative Herbivory
How Insects Affect Plants Seed dispersal Photo:Benoit Guenard Positive Insect Plant Negative Frugivory - seed destruction
How Insects Affect Plants Predation/ Parasitism Positive Insect Plant Negative
How Insects Affect Plants jeffcogardener.blogspot.com Positive Insect Plant Negative Anti-predator defense Photo: Marin Rice cirrusimage.com
How Insects Affect Plants Positive Insect Plant Negative Spread disease Photo: Jude Boucher Cucurbit Yellow Vine Disease squash bugs
Net Effect = Sum of Interactions Insect 1 Insect 3 Plant Performance Insect 4 Insect 2 Implications for both agriculture and ecosystems
Physalis longifolia study system Mary McCauley, Berea College (2004); Maggie Triska, Viterbo University (2005); Jacob Elstein, Virginia Tech (2005); Cedric Jones, Howard University (2006); Brandon Lingbeek, Calvin College (2007); Linnea Meier, Earlham College (2008); Alysia Soper, Luther College (2008); Ricky Rivera, UPR-Bayamon (2009); Stephanie Cruz-Maysonet, UPR-Bayamon (2010)
Generalists Specialist Stored Energy Flower Production Fruit Maturation Fruit Induction Seed Production
Why might specialists be important? Generalist foraging strategy when several acceptable hosts Specialist foraging strategy or generalist strategy if the generalist acts as a temporary specialist
Recapture and movement of specialist and generalist pollinators of Physalis during 2004 and 2005
Plot Visits per Survey Hour for Each Species 7 July 7-14, 2004 6 July 15-22, 2004 July 23-30, 2004 5 4 Visits per Survey Hour 3 2 1 0 Colletes Lasiogl. Augochl. Epeolus Bombus
Number of flowers visited per plot visit per species 6 5 4 Flowers visited per plot visit 3 2 1 0 Lasiogl. Colletes Augochl Epeolus Species
Fruit Initiation From Single Visits 1.0 p < 0.05 0.8 0.6 Proportion Fruits Initiated from Single Visits 0.4 0.2 0.0 Colletes Lasioglossum Augochlorinae
Pollinator Conclusions The specialist prevails in abundance flowers visited pollination efficiency pollen dispersal
Pollinators Pollen Deposition Stored Energy Flower Production Fruit Maturation Fruit Induction Seed Production
What Governs Presence of Herbivore? Susceptible Genotypes? Induced defenses? Predation?
Survival to Mature Larva of 10 Lema Placed on 10 Caged and 10 Uncaged Plants NOTE TO SELF --THESE PICTURES DO NOT DISPLAY REU student Brandon Lingbeek
One cause of mortality to Lema eggs Q1: Early season decline not explained by late season predators or parasites. Nocturnal predators? Plant is saved by whatever is controlling early herbivores.
Predation Interaction web for Physalis longifolia Parasitism Pollen Deposition Stored Energy Flower Production Fruit Maturation Fruit Induction Seed Production Frugivory Foliar Herbivory Predation Parasitism
Predation Interaction web for Physalis longifolia Parasitism Pollen Deposition Florivory Stored Energy Flower Production Fruit Maturation Fruit Induction Seed Production Frugivory Foliar Herbivory Predation Parasitism
Bee Diversity and Plant Utilization Patterns 20,000 spp worldwide 140 (so far) at Blandy Center of Diversity: arid areas –southwestern USA, Mediterranean Diet: pollen and nectar
Variation in Pollen Chemistry Constituent Max Min % Starch 23.7 0 Calories/g 6750 4407 % Protein 60 2.5 Amino acid variation: ?? Toxicity??
Ongoing Research: Understand the plant traits that influence insect foraging decisions, and the results of those foraging decisions on insect development
What Is Known About Pollen - Bee Interactions? Extremely important Pollen varies in many ways Bees make flower choices based on accessibility nectar reward floral color floral odor Q2: Do bees recognize quality and adjust choice? What are the characteristics of quality? What plants (either natives or invasives) may best support wild pollinator populations?
Specific Possible Avenues for Inquiry Herbivory on wild tomatillo: What early season factors protect the plant from an enemy that could destroy all of it? Foraging Cues: What pollen traits influence larval development and body size in bees? Do bees recognize them?
Research Areas Why pollinators choose the plants they do Nutritional quality of pollen The implications of foraging choices of pollinators on success of their host plants Why herbivores choose their host plants What governs herbivore populations Potential Applications Understanding how to promote wild pollinators in agriculture Understanding ecosystem level processes to control pests