plant-plant interactions

Question 1

briefly introduce me to plant-plant interactions

Answer 1

neighbouring plants provide a direct threat, in the form of competition
- they are much more chronic biotic threat compared to parasites
however, sometimes plants can benefit from each other

Question 2

Tell me some ways plants can detect each other

Answer 2

Light: absorbed, reflected and scattered light creates a unique cue of neighbour plants
Touch: plants are sensitive to physical touch, via trichomes and root tips
chemical VOCs: Plants produce VOCs actively and passively, and neighbour plants can detect this and produce their own
chemical signals: some evidence root exudates are complex enough to be used to identify and differentiate neighbours.
acoustic and electric signal

Question 3

what types of negative interaction are there?

Answer 3

Resource competition

interference competition (substance from one plant is dangerous to another

parasitism

Question 4

What are the two resource competition theories?

Answer 4

concentration reduction theory: whichever plant can reduce soluble resources to the lowest possible amount, and persist in this environment, will be competitively superior

pre-emption theory: plants outcompete others by pre-empting the resource supply from coming into contact with other plants. Essentially growing roots more

Question 5

How can interference competition happen?

Answer 5

Allecopathy (Alleochemicals) is the release of chemicals that stunt growth, development, survival and reproduction
-exuded into rhizosphere
-emitted as VOCs
-deposited in pollen
-released in decomposition
However, is a metabolically expensive activity

Question 6

How do parasitic plants operate?

Answer 6

Connect to vascular tissue of host plant and take nutrients and water. Produces haustoria
Hemiparasites: Facultative parasite that derives nutrients from plant, however still carries out some photosynthesis
holoparasites: Obligate parasites that have lost all chlorophyll

Question 7

Plants can aid each other. what is this referred to by?

Answer 7

plant-plant facilitation
It is driven by biotic and abiotic factors and occurs when these are limiting.
It occurs when a plant increases the availability of a resource to its neighbours.