W6, Sampling and decision making - INCOMPLETE

Question 1

Why is sampling so important in IPM?

Answer 1

Without a good understanding of how the population densities and dynamics of the pest(s) and their natural enemies affects crop value, it is unlikely that the right control measures are going to be implemented at the right time.

Question 2

Explain the difference between accuracy and precision.

Answer 2

Accuracy: How close a value is to the true value

Precision: How certain the estimated mean is (i.e. how close the measurements are to each other, regardless of how close they are to the true value).

Question 3

How should sampling data be recorded (i.e. what should be included)

Answer 3

Always report the mean and an indication of variability

• SD
• SE
• Confidence interval (90%, 95%, 99%)
• Range of values (minimum & maximum)

Question 4

What are the two alternatives for assessing plant disease?

Answer 4

• Disease incidence (% plants infected)
  
  • easier to measure
  • less subject to error
• Disease severity (% surface area affected by disease)
  
  • better beasure of effects on plants