Flower & Fruit Injury

Codling moth in apple

Apple scab on apple (right)

Left: Western flower thrips feeding injury on impatiens.

Above: Bean pod mottle virus in soybeans (left) vs. uninfected beans (right)

Weed Effects

Weed Groups• Algae (aquatic systems)• Mosses/liverworts (turf & nurseries)• Ferns/horsetails (pastureland, horticultural

crops)• Gymnosperms (rangeland, forests, long-term no-

till systems)• Angiosperms [monocotyledon & dicotyledon]

(annuals, biennials, perennials)

Weed Impacts

• Competitive -- yield loss (quantity and quality)

• Parasitic effects (cf Norris et al., p 23 – 24)• Mechanical interference with farm

implements• Other incidental

– Seed contamination– Land valuation– Health & safety (hay fever, toxins, fire hazard)

Comparative Biology of Pests

Chapter 5 is divided into 3 principal segments

1. Concepts in Pest Population Regulation

2. Dissemination, Invasion, and Colonization Processes

3. Pest Genetics

Comparative Biology of Pests

• Concepts in Pest Population Regulation1. Reproduction

2. Fecundity & Fertility

3. Population Generation Time

4. Longevity & Mortality

5. Quiescence and Dormancy

6. Heat Summation & Degree Days

7. Molting & Metamorphosis

8. Life Tables

9. Basic Life Cycle Models

1. Reproduction

Good for IPM Bad for IPM

Sexual 1. Can manage resistance

2. Mating disrupt. possible

More plastic, better able to overcome tactics

Asexual 1. Strain/race geographically specific

2. Can’t overcome effective controls

1. More inoc. (path & weed)

2. Faster popn. growth (all are reproductive)

Note: Many serious species have both sexual & asexual periods or stages.

Individual and Population Development Time

• Includes:2. Fecundity & Fertility

3. Population Generation Time

4. Cycles per Season

5. Longevity and Mortality

• Affects management response time

Management Response Time

• The amount of time between when a decision to control a pest is made and when that control takes effect.

• Primarily used for rescue treatments.

• Directly affects action thresholds.