P-I Interactions

Question 1

How do herbivores injure plants?

Answer 1

1 - They remove tissue or photosynthate
2 - They inject or secret chemical substances into the plant during feeding which facilitate penetration of stylets and help digest plant tissue.

Question 2

Direct x indirect herbivores.

Answer 2

Direct herbivores feed on harvested parts of the plants such as grains, roots, etc. Indirect herbivores feed on parts of the plant that will not be harvested.

Question 3

Types of injury?

Answer 3

Defoliation
Leaf-feeding
Clipping
Boring
External xylem sucking
"Chemical"
Seeds
Internal stems
Galls
Roots
Leaf-folders
Leaf-miners

Question 4

Yield losses: potential loss x actual loss

Answer 4

Potential losses are projected losses without crop protection practicie - how much loss if you didn’t do anything?
Actual losses are crop losses sustained even with control measures.

Question 5

Origin of insecticides and problems related

Answer 5

The beginning of insecticide era starts with DDT on WW2 to control insect-vectored diseases. After WW2, insecticides were applied in agriculture (crops, forest, orchards, etc) and its indiscriminated use caused several issues such as insecticide resistance; non-target effects; pest resurgence; secondary pests, and environmental contamination.

Question 6

IPM definition

Answer 6

IPM is a DECISION support system for the selection and use of pest control tactics, singly or harmoniously coordinated into a management strategy, based on cost-benefit analysis that take into account the interests of and impact on producers, society, and the environment.

Question 7

What were the 3 historical trends that led the emergence of the IPM concept?

Answer 7

Problems with insecticide-based control
Increased awareness of environmental contamination in society
Globalization of western agriculture

Question 8

What problems led the re-evaluation of overreliance on insecticides?

Answer 8

Insecticide resistance
Non-target effects
Secondary pests
Pest resurgence
Environmental contamination.

Question 9

Discuss the impact of the book “silent spring” by Rachel Carson

Answer 9

Published in 1962, this book brought public attention to potential effects of pesticides on human health and the environment.

Question 10

Elaborate on the impact of green revolution.

Answer 10

During the green revolution, there was an increse of high-yielding, shot-estature, and short-season crops responsive to high N. These crops produce high yields under high-imput conditions. The encouraged global adoption of high-imput practicies increased pest problems in many crops.

Question 11

What was the first IPM paper?

Answer 11

1959 - The integration of chemical and biological control of the spotted alfalfa aphid by Vernon Stern published on hilgardia.

Question 12

What are the five principles of IPM?

Answer 12

1 - Management, not erradication!
2 - Know your enemy - IPM as applied biology and ecology
3 - Use pesticides only when their use is justified by cost-benefit analysis.
4 - Integrate use of all appropriated management tactics
5 - Contextualization of pest managment: other pests, agronomic practicies, society, and environment.