Species interaction Flashcards
Name 3 category of species interaction
Antagonistic
Mutualistic
Plant-plant communication
What is mutualism?
+/+
Individuals of 2 species live together and BOTH benefit
What is parasitism?
Individuals of 2 species live together, one member benefit while other is harmed but not killed
Name 3 types of antagonistic interactions
Plant-plant (parasitic plants)
Host-parasitoid
Predator-prey
Name 2 types of mutualistic interactions
Plant - pollinator
Plant - seed dispersor
Name 2 types of plant-plant communication
Allelopathy
Mycelial networks
What are some classification of parasitic plants?
Holoparasite
Hemiparasite
Root/stem parasite
What is a holoparasite
Plant parasite
- obligate parasite
- Produce no chlorophyll, and are totally relient on the host
What is a hemiparasite?
Plant parasite
- Derive some of their nutrition from the host, but produce chlorophyll and are functionally photosynthetic (ex mistletoe)
What is a root/stem parasite?
Plant parasite
- Whether the parasite attaches to the root or stem system of the host plant (ex: Striga spp. or witch weed)
What is striga?
Plant parasite
=> hemi/holoparasite of roots (all except 3 genera)
- Parasite on cereals
- One of the most destructive plant pests in Africa
- Affects 40% of Africa’s subsahara region, resulting in about 13 billion US$ loss every year
- Striga infest 40 million hectares of crops in subsaharan Africa alone
- Seeds can survive for 10 years
What are some control options against Striga spp.
- Hand pulling before seed production stage
- Planting trap crops => suicide germination (seeds germinate, but cannot attach to the roots)
- Tolerant crop varieties
- Biological control agents (fungal pathogens)
What is a difference between a parasite and parsitoid?
Parasitoid=> causes death of the host
What are ectoparasitoids?
Feed from the outside of their host
What are endoparasitoids?
They feed from the inside of their hosts
Can be either ido or koinobionts
What are idiobiont vs koinobiont?
Idobiont: feed on paralyzed host
Koinobiont: feed on live, active host
At what stages can host insects be attacke by parasitoids?
Egg
Larvae
Pupae
Imago
What is hyperparasitism ?
A parasite of a parasite
First primary parasitoids attack the host, and then secondary parasitoids have a primary parasitoid as their host.
What are some defense mechanisms of prey?
Mimicry
Distraction
Chemical defense
Mechanical defense
What is meat by mimicry? Give some examples
Evolved resemblance between between organisms and another object, often an organism of another species
Ex:
Batesian mimicry: hoverflies mimic stinging wasps
Stick insect camouflage
Give an example of distraction as defense mechanisms of prey
Large swarms or flocks reduce success rate of predators
Give an example of mechanical defense mechanism of preys
Turtles..
Give an example of chemical defense mechanism of preys
Beetles producing a liquid that is sticky and acidic…
Where should seeds be dispersed, what is the role of animals in seed dispersion?
Janzen-Connell Hypothesis
Seeds need to esape the mother plant.
Seeds that are dispersed farther have better chances of survival. However, probability of seed dispersal decreases as distance from parent plant increases.
What are some plant-plant communication ways?
Allelochemicals: intra/interspecific
Pheromones: only intraspecific
=> semiochemicals/messengers
These have as effect to deter herbivores, attract beneficials inform neighbours, induce immune systems
Through:
volatile organic compounds and common mycelial network
How does plant-plant communication through allelochemicals impact the plants? What plants use this type of communication?
It influences the germination, growth, survival and reproduction of other plants
- Basis of success for some invasive weeds (e.g. garlic mustard)
- Also in crop plants: rie, rye, squash, radish
What are some ways of allelochemicals into the environment?
- Volatilization from leaves
- Leaching from plant litter
- Leaching from leaves by rain, fog or dew
- Exudation from roots
- Decomposition of plant litter
Give examples of communication via VOCs (volatile organic compounds)
Acacia trees: when wounded, emit ethylenes => rise in tannin levels in trees nearby
Herbivore-induced plant volatiles that attract parasitoid wasps
What are some ways that mycorrhizae connect to plant? What is the effect/impact?
FRIENDSHIP
- ex: stess trt in Douglas tress leads to stress signalling in neighbouring pine trees via CMN => neighbors receive these messages can modify their behavior through altered morphology, physiolgy and biochem, reduce their stress and improve their fitness
SABOTAGE
ex Tagetes sends allelochemicals via the CMN to its neighbouring plants, by this reducing germination and growth
=> allelochemicals are much more effective if sent via CMN, not just via soil diffusion
FIRE ALERT
Aphid attack causes systematic changes in the production of plant volatiles making bean plants repellent to aphids
=> only if plants are connected through CMN
=> allows neighbouring plants to invoke herbivore defences before attacks
