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Listen to an Academic Talk Test #056
Listen to an Academic Talk
1. What is the talk mainly about?
A) How plants compete for resources
B) A biological process with agricultural uses
C) The chemical composition of certain trees
D) The negative effects of synthetic herbicides
2. What does the professor say about the Black Walnut tree?
A) It helps nearby garden plants to grow.
B) It releases a chemical that harms other plants.
C) Its roots are unusually long and deep.
D) It is being studied as a natural herbicide.
3. What can be inferred about synthetic herbicides?
A) They are less effective than allelochemicals.
B) They were inspired by the Black Walnut tree.
C) They are considered harmless to the environment.
D) They might have undesirable environmental consequences.
4. Why does the professor mention sorghum?
A) To give an example of a plant resistant to juglone
B) To illustrate a plant that uses allelopathy
C) To contrast it with the Black Walnut tree
D) To describe a common agricultural crop
Professor: Today we're discussing allelopathy. That's a biological phenomenon where one plant influences others by releasing certain chemicals into the environment.
These chemicals, known as allelochemicals, can inhibit seed germination or root growth in neighboring plants. A classic example is the Black Walnut tree, which produces a chemical called juglone.
Juglone is toxic to many plants, including garden favorites like tomatoes and potatoes, preventing them from growing nearby. Another plant, sorghum, releases a substance that is so effective at suppressing weeds that scientists are studying it as a potential natural herbicide.
This application is significant because it could lead to more sustainable farming practices, reducing our reliance on synthetic chemicals that can harm the environment. So, we're looking at a plant's natural defense mechanism that could have major agricultural benefits.
These chemicals, known as allelochemicals, can inhibit seed germination or root growth in neighboring plants. A classic example is the Black Walnut tree, which produces a chemical called juglone.
Juglone is toxic to many plants, including garden favorites like tomatoes and potatoes, preventing them from growing nearby. Another plant, sorghum, releases a substance that is so effective at suppressing weeds that scientists are studying it as a potential natural herbicide.
This application is significant because it could lead to more sustainable farming practices, reducing our reliance on synthetic chemicals that can harm the environment. So, we're looking at a plant's natural defense mechanism that could have major agricultural benefits.
Highlights
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