Flashcards in Pest managament Deck (68)
Define Integrated Pest management
A pest control strategy that uses an array of complementary methods (mechanical devices, physical devices, genetic, biological, legal, cultural management, and chemical management) in three different strategies (prevention, observation, and intervention) to significantly reduce or eliminate the use of pesticides
How is prevention used to construct an effective I program?
Stops pests from being introduced to a location
Regulations and quarantines are commonly used to prevent introduction
eradication is used to prevent the pest from remaining in the area if pest is already there.
How is avoidance used to construct an effective IPM program?
Keeps a species population below levels where it would be a pest
Pest target is kept healthy so pest damage is below economic threshold
Pest target can be given increased pest resistance through breeding and genetic engineering
Natural enemies can be maintained or increased
Traps can be used to lower pest population
Barriers can be used to separate the pest from host
How is monitoring used to construct an effective IPM program?
Characterized the presence/ absence of the pest and, if present the fluctuations in the pest populations
May include the degree/extent of pest damage to the host
How is suppression used to construct an effective IPM program?
Used to reduce pest populations below the economic threshold of prevention and avoidance tactics fail
Chemical, biological, cultural and other tactics are used to minimize environmental impacts
What are the steps of an IPM program?
Sampling and monitoring
Identification (kind, nature, and severity of pest damage or potential for damage)
Determining need for control (compare cost of treatment with economic benefit of treatment)
Evaluating control options
Evaluation and record keeping
How do pathogens, predators, and parasites affect insect pest population development?
Each can reduce pest populations
Pathogen causes a disease to occur in pest
Predators attack the pest and may use it as food
Parasites live on or in the pest and may use t as food
How do host plants affect insect pest population development?
Presence of a host plant increases the possibility of increased pest populations
How does the initial pest population affect insect pest population development?
The higher the initial pest population, the higher the potential for increased pest populations
Initial population of insects or insect density is modified by the spatial distribution of the insects (dispersion), their birth rate (Natality), the pattern of insect growth, and age of the insect population
May or may not lead to higher insect populations
How does temperature affect insect pest population development?
Pests grow and develop in response to thermal inputs
Each organism has a min, max, and optimum temp for growth and development which can change during a life cycle
Often insects grow and develop in response to degree days or the accumulation of heat above a threshold value
How does soil characteristics and conditions affect insect pest population development?
Soil physical properties like moisture, temp, and aeration can be important in the growth and development of some insect populations
How does wind affect insect pest population development?
Wind transports insects to new locations for infestation
Wind damage to immature plants can be misinterpreted as insect damage
How does developmental time and seasonal period of activity of an insect influence their ability to cause damage?
They are related to factors like temp, light, and food supply.
When developmental time and period of activity of the insect coincide with the growth of a host crop, damage may occur
How does the reproduction rate and number of generations per season of an insect influence their ability to cause damage?
The number of eggs (rate) and the number of generations per season combine to improve the survivability of the insect
Some insects produce large numbers of eggs, others produce many generations per season
How does over wintering and over summering strategies of an insect influence their ability to cause damage?
These help to assure that the insect will survive and be competitive
How do feeding habits of an insect influence their ability to cause damage?
Chewing insects remove plant parts where metabolic activities occur or fruiting structures of plants
Piercing-sucking insects remove the internal fluids of the plant, interfering with metabolic activity
Insect activity can also damage plants by vectoring disease
What are the 3 types of metamorphosis?
None/without/simple: egg, young adult with young looking like adult but smaller and feeding on same food source as adult
Gradual/simple: egg, naiad, adult. Naiad look generally like adult but without wings and external genital appendages. Each time naiad goes through feeding stage (instant) followed by a molt it looks more like the adult. All immatures are aquatic and have gills with different food sources for adults and immatures
Complete/complex: egg, larva, pups, adult. Larvae go through series of growth stages and molts but remain worm-like. Food source may or may not be the same. Many species undergo complete metamorphosis
What are the three keys to maximizing disease development and damage to crop?
Environment must be optimum for pathogen growth
Host must be highly susceptible to the pathogen
Pathogen must be abundant , active, and virulent
How do fungi survive between crops, move field to field, and infect plants?
Survival: mycelia, spores, sclerotia in infect plants, debris, soil, insects
Movement: dispersal by wind, water, insects, animals, humans
Grow through cell (intracellular mycelium) or between cells (intercellular mycelium)
How do bacteria survive between crops, move field to field, and infect plants?
Survival: in infected plants, debris, soil, insects
Movement: dispersal by water, insects, animals, humans
Infection: invade plant tissue through the cells (intracellular) or between cells (intercellular)
How do viruses survive between crops, move field to field, and infect plants?
Survival: in living tissue, insects, nematodes
Movement: dispersal by insects, humans
Infection: invade plant tissue through the cells (intracellular)
How do nematodes survive between crops, move field to field, and infect plants?
Survival: eggs in soil, eggs and nematodes in roots, some larva and adults in seeds or bulbs
Movement: dispersal by water, animals, humans
Infection: invade plant tissue through the cells (intracellular) or between the cells (intercellular)
How does weed growth rate affect the competitive ability of weed populations?
High growth rate makes it more possible for the weed to intercept light and shade the crop, and to have a large root system which will extract water and nutrients needed by the crops
Early emergence also increases competitiveness
How does weed seed production affect the competitive ability of weed populations?
High seed production increases the likelihood that the weed will remain at competitive populations in the field
How does weed seed dormancy affect the competitive ability of weed populations?
Seed dormancy will ensure the weed will survive in the field for years allowing it to reappear at competitive levels when the dormancy is broken
How does weed reproduction method affect the competitive ability of weed populations?
Weeds reproduce by seed and vegetative growth
Seed variability, seed dormancy, and seed numbers are important for weeds that produce seeds
Vegetative reproduction is common for perennial weeds where they reproduce from stolons, rhizomes, bulbs, aerial bulblets, comes, tubers, or tap roots (these asexual reproductive parts are hard to control culturally)
How does weed life cycle affect the competitive ability of weed populations?
Weeds that germinate before crop plants germinate and grow rapidly while the crop is small are more competitive.
Weed survival depends on the ability of the weed to complete its life cycle, including production of viable seed that remain viable in the soil for extended periods, and/or maintenance of vegetative reproductive structures
What are advantages/disadvantages to direct observation?
Advantage: no equipment needed, good for small plants
Disadvantage: careful observation a must, more difficult in dense plant stands
What are advantages/disadvantages to sweep net and drop cloths?
Advantage: inexpensive, can be used to sample many pests
Disadvantage: sweeping efficiency varies from person to person, insects per sweep is not a direct measure of population per area