Compare and contrast the insect life-history strategies of polyphenism, migration and diapause. How do the patterns of environmental and biological triggers for these life-history strategies relate to whether an insect undertakes migration or diapause in its lifetime? How do these life history strategies impact on pest management practices? Use specific examples to support your answer.

 

Answer:

Comparison between insect life-history strategies of polyphenism, migration and diapause
a) How the patterns of environmental and biological triggers for this history in relation to migration or diapause 
There are environmental patterns that triggers the life history of insects in relation to migration. These factors may include wind and temperature. Wind affects insect's landing patterns and the locomotory behaviors that precede landing-including the direction from which the insects approach a landing target, and changes in the body attitude and velocity. For instance, the movement of locust during their outbreak was majorly influenced by wind. On the other hand, increased temperature could decrease pest insect populations (Tougeron, 2019). For instance, some insects are closely tied to a specific set of hot crops. Temperature increases that cause farmers not to grow the host crop any longer would decrease the populations of insect pests specific to those crops.  
b) How these life history strategies impact on pest management practices  
Researchers have therefore been finding new ways on how they can be able to control the rate of insect migration on areas with high temperatures which may led to insect migration. they have then come up with a 'rule of thumb' for insect management by freezing is to maintain a temperature in the insect's microhabitat of 0-10F for a minimum of 7-10days. On the other hand, scientists make the proper pruning and training of young trees, and also contribute in controlling wood-damaging insects which shall help to prevent wind damage. In some other gardens, farmers may create windbreakers or even plant several trees clumped together which may lessen their damage at windy sites.
References 
Tougeron, K. (2019). Diapause research in insects: historical review and recent work 
perspectives. Entomologia Experimentalis et Applicata, 167(1), 27-36.