Pest Management

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explain how strip cropping affects pest mng decisions

(growing crops in alternate strips) can be used in the same manner as crop rotations--in areas subject to wind and sand damage, strip cropping is most beneficial

the WPS specifically requires:

-information about pesticide exposure -protection from pesticide exposure -mitigation of exposures that occur: decontamination sites..

describe how to store and transport pesticide safely and securely

-locked in a separate enclosure, room or building -heat to prevent freezing -ventilation to prevent inhaling -adequate lighting -pallets or shelves for sacks, cartons and boxes -signs posted, warning of pesticides -safety equipment for spills or exposure

describe WPS for handling pesticides

-must be displayed in a central location -pesticide safety training -decontamination sites -information exchange between employers of ag workers and pesticide handlers -emergency assistance

describe how solubility, persistence and soil absorptive characteristics of a pesticide affect soil and water quality

-pesticide adsorption by soil colloids decreases the potential for movement to the groundwater and increases the potential for movement with eroded soils -pesticide solubility affects the amount of pesticide that can leach or runoff--more soluble pesticides tend to be more mobile -pesticide degradation and persistence are opposites--increasing degradation decreases the possibility of movement to soil surface water and groundwater

evaluate a site's vulnerability to soil and water contamination from pesticides

-runoff increases the potential for movement of pesticides (dissolved and absorbed) to surface water -depth to the water table doe not affect movement, but shallower tables are more prone to pesticide contamination -soil texture impacts movement of water, the adsorption of the pesticide by soil colloids and the decomposition of the pesticides

use root system to ID weeds

-tap root: main root grows downward -fibrous roots: thin, threadlike roots usually without a primary root present -adventitious roots: root growing from something other than root tissue -tuberous root: root enlarged for storage of food reserves -aerial root: adventitious root produced above ground, often for climbing

explain the types of metamorphosis

1. none: (without or simple) the stages of development are egg, young and adult--when an insect hatches, it looks just like an adult, but smaller and feed on the same food source 2. gradual/simple: the stages are egg, naiad and adult--at hatching the insect look similar to adult but without wings--each new molt is called an instar--all immatures are aquatic and have gills for respiration--food source is different for adults and immatures 3. complete/complex: the stages of development are egg, larva, pupa and adult--larve molt often but remain worm-like--food source for larve and adult may or may not be the same--inactive during pupa but is changing to adult stage

explain how feeding habits affect an insect's ability to cause damage

2 main feeding habits: 1: chewing insects injure plants by biting, tearing or pinching off pieces of plant--2:piercing-sucking insects remove the internal fluids of the plant, interfering with growth--insect feeding can also vector diseases

distinguish action threshold from economic injury level

Action threshold (AT): a pest pop and/or associated injury when a pest control will prevent the economic injury level The EIL: a point where pest mng costs equal loss in income due to the damage from the pest--above EIL, income loss will occur unless the pest is controlled

list the adv and dis of incorporating multiple traits into a crop with transgenic techniques

Adv: chemical applications reduced or eliminated if genetically engineered crop controls pests -multiple pests can be controlled at the same time -fewer trips across the field with implements or aerial application -less mng required -eliminated env. problems Dis: yield may be less -cost of seed is higher -pests may develop resistance

define best management practices

BMPs are research based and designed to optimize agronomic production and env. protection--BMPs are actual production practices such as use of minimum tillage, buffer strips and proper fertilizer rates to protect ground and surface water

EIL example

Fungicide= $15/acre Crop= $4/bushel Crop loss= 10% less the yield of the crop before disease= 70 bu/acre EIL = ($15/acre) / ( $4x.1x70bu)= 0.53 Income loss: ($4/bu)(.1)(70/bu)= $28/acre crop loss EIL<1 and the treatment cost is less than income loss

advantages of IPM

IPM offers alternatives to traditional approaches which are aimed at eradicating pests--IPM focuses on managing pests in an economic, environmental and socially safe manner

re-entr interval (REI)

REI is a time period immediately after pesticide application where entry to a field is limited

bacteria survival, movement from fields and infection

Survival: in infected plants, debris, soil and insects movement: dispersal by water, insects, animals infection: invade plant tissue through the cells (intracellular) or between cells (intercellular)

fungi survival, movement from fields and infection

Survival: mycelia, spores, sclerotia in infected plants, debris, insects Movement: dispersal by wind, water, insects, animals infection: growth through cells (intracellular) or between cells (intercellular)

recommend insecticide timing of juvenile hormone

These materials are also called Insect growth regulators—applied at the right point of metamorphosis of an insect, these materials kill the pest

describe how Bt crops affect pest management

a Bt modified crop can be used in place of insecticides whihc reduces insecticide use in the crop--refuge areas planted to the same crop but not containing Bt must be planted nearby to reduce genetic resistance in insects

ID moth characteristics

abdomen and wings have miniature scales--immatures are caterpillars--Geometrid Moth are wingless

ID white flies

adults have four wings covered with white dust--immatures are nymphs

list adv/dis of sweep net/drop cloth for sampling insects

adv: inexpensive, can be used to sample many pests dis: sweeping efficiency varies from person to person--insects per sweep is not a direct measure of insect pop

list adv and dis of aerial applications

adv: large areas sprayed quickly, use where ground rigs cannot go, no physical damage to crop dis: more drift, costly, weather

list adv and dis of ground rigs

adv: less drift, cost-effective for smaller areas dis: slow, timeliness, soil compaction, crop injury

list advantages and disadvantages of direct observation for sampling insects

adv: no equipment needed, good for small plants dis: careful observations are a must, more difficult in dense plant stands

list adv/dis of insect traps for sampling insects

adv: traps specific insects of interest dis: only trap insects that will move to the trap

describe required proper clean up procedures for application equipment and gear

after use: rinse in clean water then wash in hot water using detergent--repeat washing if pesticide color or oder remains on gear--dry outside--rinse washing machine by running cycle with detergent application equipment: washed with detergent/water mixture and after removing sprayer nozzles and screens, rinsed twice with clean water--nozzles and screens should be cleaned separately--all cleaning solutions should be contained for proper disposal

describe weather data for monitoring pests

air temp is used to calculate heat units--heat units are added each day by subtracting temp above a min. temp (set), from a max temp for the day (unless there is a max temp also)--degree days can help to decide when to begin monitoring--weeds should be monitored right after planting

evaluating and record keeping of IPM strategies

all plans should be evaluated and refined during and after implementation--monitoring after implementation and keeping records is important

define and describe the differences between alternate hosts and alternative hosts

an alternate host does not replace another host, just the second choice--an alternative host replaces another host

define pest

an organism that damages another organism--in crop production this can be weeds, insects, diseases and pests

list factors that increase the risk of crop injury from pesticides

application near sensitive crop, improper aerial application, wind, high temp which increases volatilization, use of small droplets, high pressure, high boom height

explain how carrier volume affects spray drift

as carrier volume decreases, droplet size decreases and drift potential increases when ultra-low volume sprayers are used

describe how selection pressure affects pest resistance to pesticides

as selection pressure increases, pest resistance tends to increase

life cycle of insects

at each stage in their life cycle, an insect or mite have different characteristics

ID temp extremes on crops

at high temps, enzyme systems are altered or inactivated--at low temps, ice forms between plant cells and then within cells disrupting them

describe how avoidance constructs an effective IPM program

avoidance keeps a specie pop below levels where it would be a pest--pest target (host) is keeping healthy so that pest damage is below the economic threshold--natural enemies of the pest can be maintained or increased--traps can be used to lower pest pops and barriers can be used

explain the advantages and limitations of using biological control agents in crop production

biological control agents are used to control a specific pest--BCA that are not morally indigenous to the location are usually the best for control--increasing native populations is usually less successful--limitations include: lack of broad spectrum control (one host), potential damage to off-target organisms

ID pigment inhibitor injury (12, 13, 27-HPPD)

bleaching (white) existing leaves

describe how herbicide resistance affects pest mng

broad spectrum herbicides can be used to control many weeds--long term of these herbicides can result in resistant weeds

ID soil compaction damage to crops

can hinder root growth and limit the volume of soil that plant roots can explore for water, oxygen and nutrients--water can pond on compacted soils due to reduced infiltration

explain how pre-harvest intervals affects pesticide selection

certain pesticides cannot be used within a given period of time prior to harvest

explain how nutrient status affects pest mng decisions

changing soil pH, allowing soil to remain dry or flooding a soil can be used to control a pest--improving plant growth and development can also be used to reduce damage from pests--excessive nutrients can stimulate disease

ID nitrogen metabolism inhibitors (liberty)

chlorosis of entire plant in 4-5 days

ID amino acid synthesis inhibitors (2-ALS)

chlorotic new growth to death, depending on rate

define chronic and acute pesticide poisoning

chronic occurs after repeated exposures to small doses--acute toxicity occurs after one large dose

ID seedling root and shoot growth inhibitors (3=root/microtuble, 8, 15)

clubbed root tips or leafing out underground, wrapped leaves, buggy whipping

describe how to obtain, prepare and ship insect samples to a lab

collect insect, place it in a vial with rubbing alcohol and seal lid--ship to lab for ID

describe how to obtain, prepare and ship diseased plants to lab

collect whole plant, including root system--shake soil from roots but do not wash--enclose roots in a plastic bag and then enclose the whole plant in a second plastic bag--if cannot collect whole plant, collect infected part and put in plastic bag--do not add moisture to roots or foliage--refrigerate before shipping

describe how to obtain, prepare, and ship weed samples to a lab

collect whole weed, including roots--dry excess moisture, place in plastic bag, and refrigerate--send to lab asap

describe how forecasting models affects monitoring pests

computer models that use weather, crop and potential for diseases and insects predict when and where a disease outbreak may occur--models can predict economic thresholds

implementing an IPM

consider all factors and compare to cultural, biological and pesticide alternatives--choose the least cost, most effective and env. friendly alternatives--cultural and bio alternatives should be used as much as possible

ID cell membrane disruptor injury (PPO, 14)

contact burn of existing leave, chlorosis of veins if soil uptake (heart shaped soybeans)

identify plant injury symptoms cause by photosynthesis inhibitors (5-7)

contact burn of existing leaves, chlorosis of oldest leaf margins of seedlings if soil uptakes

distinguish between contact and systemic pesticides

contact: kills the plant where the spray hits the plant--systemic: moves the spray throughout the plant, to the site of pesticidal action, killing the whole plant

describe how to prevent pest resistant populations of insects, weeds and diseases

continued use of pesticide leads to genetic changes within the pest population as resistant members are selected over member susceptible to the pesticide--over time, the pest can withstand normal concentrations of the pesticide--applying higher concentrations accelerates the problem

describe how level of infestation or infection helps monitor pests

continuous monitoring can be used to estimate pest population dynamics that cause economic damage levels--the time to begin monitoring is dependent on degree days, time of year, crop growth stage

distinguish conventional resistance and transgenic resistance

conventional plant breeding is an approach where genetics are used to develop crops that are resistant to to a pest--resistance means that the plant can exclude or overcome the pest--transgenic resistance of a crop to a pest is resistance obtained from genetic material of another species of plant or animal

ID aphid characteristics

cornicles protruding from ends of abdomen (joysticks)--immatures look like adults but shorter

describe the concept of critical weed free period

critical weed free period of a crop is the time during the growing season when the crop must be free of weeds--if not, yield will decrease

explain how crop residue affects pest mng decisions

crop residues are a host for disease and insect populations, so destroying the host is an effective way to reduce the pest pop

explain how crop growth stage affects pesticide selection

crop sensitivity to a specific pesticide can vary--some crops can metabolize a herbicide, causing no injury--pesticides that will damage a crop at a certain growth stage are poor choices in a pest control program for application during that time

describe the competitive interactions between crops and weeds

crops and weeds compete for light, nutrients, space and water--a vigorously growing crop that can compete for these factors can reduce weed growth and vice versa--smother crops are dense stands of crops that compete very effectively with weeds for space, light, nutrients and water, reducing weed growth--competitive crops will out-grow weeds, shading out the weeds and decreasing their growth--competitive weeds do the same

how does cropping history affect mng decisions

crops in previous years can serve as hosts for pests or do not allow pests to live there

explain how to use crop grown to help ID a pest

diseases and insects are often associated with one or more hosts during part of their life cycle

explain how to use symptoms and patterns of damage

diseases have characteristic symptoms that vary with plant part, time of year, weather, crop and so on

ID growth regulator injury (4)

distorted growth of new leaves, twisted stems

explain how pathogens, predators and parasites affect population development

each one can reduce a pest pop--pathogen causes a disease to occur in a pest--predators attacks the pest and use it as food--a parasite lives on or in the pest as food

describe what procedures to follow if a pesticide gets on skin, eyes mouth or stomach or inhaled

each pesticide is unique--the labels have info on first aid treatment--if exposure occurs, follow label

explain how to use distinguishing characteristics of pests

each weed, insect, and disease has observable characteristics

use auricles

ear-like lobe on grasses

determine the EIL

economic factors center upon the relationship among the EIL (pest/acre), the pest mng alternative C ($/acre), value of the crop sold V ($/lb), injury amount I (% loss/pest/acre) and damage per injury amount D (lbs/acre/% loss) - EIL= C/(V x I x D) - when EIL is less than 1, a treatment is cost effective so C< VxIxD and the cost of treatment is less than the income lost from pest damage

explain how reproduction rate and number of generations per season affect insect's ability to cause damage

eggs of insects are generally placed in a suitable and protective environment near a food source --the number of eggs (rate) and number of generations per season combine to improve the survivability of the insect--some insects produce large number of eggs while other produce many gen per year

info exchange requirements

employers of a commercial pesticide handlers must inform customers about: -where to apply pesticide -time and date of pesticide -product name, EPA registration number -REI -written and oral notification Operators of ag establishment must inform worker protection during and application: -location of where they sprayed -commercial handlers within 1/4 mile of workers -restriction on entering treated areas

use hairiness to ID weeds

features include: -presence -density -on leaf sheath, margin of leaf -on collar

use cotyledons to ID weeds

features include: above or below ground cotyledons, presences or absence of lobes, length vs width, thickness, color, shape, pubescence

use ligule to ID weeds

features: -presence or absence -membranous -shape -fringe/hairs -margins

identification step of IPM

field scouting and history are used to determine the kind, nature and severity of pest damage or the potential for damage

mode of action fungicide

fungicides have multiple MOA

ID lipid synthesis inhibitors (1--fops and dims)

growing point rots, new leaves pull out easily

site decontamination procedures

handler employers must provide a place where pesticides and pesticide residues can be wash off during pesticide handling--worker employers must provide place where pesticides can be washed off if the worker is in the pesticide treated area until 30 days after REI

explain how harvest method and date affect pest mng decisions

harvesting prior to conditions where disease can develop on seed or other harvestable plant parts increases crop quality and decreases the presence of disease in later years

explain how furture cropping plans affect pesticide selection

herbicide carryover to a susceptible rotational crop should be considered in future cropping plans--minimizing development of herbicide resistant weeds is also a consideration

describe how growth rate of weeds affects the competitive ability of weed populations

high growth rates make 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 crop

describe how seed production of weeds affects the competitive ability of weed populations

high seed production increases the likelihood that the weed will remain at competitive populations in the field

list how ground speed affects pesticide coverage

higher ground speed equals more drift

list how spray viscosity affects pesticide coverage

higher spray viscosity equals less drift because the solution is denser

how does pesticide injury affect mng decisions

history of pesticide use provides info about which materials are most effective and the development for pest resistance

describe how resistance mechanisms affects plant resistance to pesticides

if resistance is due to changes in a single gene, it occurs more rapidly than if resistance is due to multiple genes

explain how soil characteristics affects pesticide selection

if the pesticide is soil-applied, differences in soil texture, OM and pH can affect pesticide efficacy and should be considered

describe how pest reproduction methods affect plant resistance to pesticides

if the pesticide targets the organism before reproduction, surviving members of the pest population will have pesticide resistance--organisms that reproduce sexually and have short life cycles are more prone to pesticide resistance than organisms that reproduce asexually and have long life cycles

describe how water contaminants (clays, OM) affect the efficacy of water applied pesticides

if water contains clay, OM, the concentration of pesticides that are strongly adsorbed by clay and or OM can be reduced and efficacy declines

describe how aerial imagery affects monitoring pests

imagery can used to ID areas where crop damage has occurred--satellites are used to find large areas of damage

list the limitations of IPM

implementation of IPM program requires adoption of new set of protocols and strategies to control pests--the main barrier to implementation is unwillingness to adopt these new practices

define integrated pest management (IPM)

in Ag, IPM is a pest control strategy is a pest control strategy that uses a variety of methods such as mechanical, physical, genetic, biological, cultural and chemical management--done in 3 stages: 1. prevention 2. observation 3. intervention--it is an ecological approach with a main goal of significantly reducing or eliminating the use of pesticides

describe how env., host plant and pathogen interact to result in plant disease

in order to maximize disease development and damage to the crop, the env must be optimum for host growth, the host must be highly susceptible to the pathogen, and the pathogen must be abundant, active and virulent

explain how dispersal and movement strategies affect insect damage

insect mobility can be active (walking, flying) or passive (carried by wind, water, animals)--mobility allows an insect to survive by moving to an optimum environment

how do refuge locations affect pest mng decisions

insect refuges are locations where a crop without insect control genes is planted to reduce resistance in an insect population

how does future cropping plans affect pest mng decisions

insect, disease, nematode and weed control strategies for can impact these pests in future crops--ex is herbicide carryover--

explain how moisture affects a pest pop development

insects are sensitive to moisture extremes--irrigation and soil drying are used to control insect pops--the growth development can vary with humidity--diseases that affect insects or hosts can also vary with humidity

recommend insecticide timing and placement based on contact insecticide activity

insects at earlier stages are more susceptible than older insects--contact poisons enter the insect when the insect is contacted with the chemical--so the insecticide must be applied on the appropriate part of the plant at the appropriate time in order to ensure good application--contact may me touch, ingestion or inhalation

explain how to use distribution in a field to distinguish pests

insects have a characteristic distribution in a field while diseases may be found on particular plant parts

biological control agents

insects that control pest insects--lacewings, ground beetles, lady beetles, minute pirate bugs, damsel bug, parasitic wasp (aphid wasp), predatory mites, spiders, syrphidfly larvae

describe how to manage herbicide resistant weed populations

it is important to avoid continued use of high rates of pesticide with same mode of action--varying modes of action reduces the potential for development of herbicide resistant populations

use info about current crop pest data to make pest mng decisions

knowledge of the impact of current populations of weeds, insects, diseases on future growth of a crop is fundamental to making good mng decisions

ID sunlight damage to crops

lack of sunlight leads to lower photosynthesis= spindly, elongated plants--excessive light leads to temp damage

list how nozzle characteristics affect pesticide coverage

larger nozzle tips at lower pressure (larger droplet size), wider angle tip allows for less drift (boom is higher off ground)

use arrangement, shape and vein pattern of leaves

leaf arrangement features include: -alternate -opposite -whorled leaf morphology includes: -types: simple, compound -margins: (lobed, hairy, toothed) -shapes -surface (waxy, hairy) -vein characteristics -color

ID beetle (weevil) characteristics

long, extended mouthpart--immature are larve

list how boom height and configuration affect pesticide coverage

lower boom height equals less drift (spray closer to ground

list how evaporation rate affects pesticide coverage

lower evap rate equal less drift because there is more of a chance that droplets will reach ground, target crop or pest

list how spray pressure affects pesticide coverage

lower pressure equals less drift because of larger droplets

list how wind speed affect pesticide coverage

lower wind speed=less drift (less energy to carry droplets)

describe the affects of potential pesticide loss from a field

maintaining crop residue on the soil surface, buffer strips, contour farming and subsurface drainage increase infiltration rates and decrease runoff--each practice reduces pesticide loss

ID mite characteristics

mature have 8 legs--immatures look like adults, but much smaller

describe how to use sampling and monitoring steps of an IPM program

methods for sampling plant and pest material will vary with crop and pest--each method should provide a sample that can be assessed, providing useful info to base a management decision--some factors considered while sampling are: what to sample, when to sample, how frequently to sample, and how many subsamples should make a sample

type and number of legs to ID insects and mites

mites: 0-8 legs insects: 6 legs

describe how monitoring constructs an effective IPM program

monitoring characterizes the presence or absence of the pest and, if present the fluctuations in the pest pop--monitoring may include the degree of damage to the host

describe how crop growth stage affects monitoring pests

monitoring should begin prior to crop growth stage where damage is important

describe how pest development stage affects monitoring pests

monitoring should begin prior to the pest development stage where damage is important

describe how time fo year affects monitoring pests

monitoring should begin prior to the time of year where the damaging stage of the pest appears

describe how broad spectrum vs narrow spectrum applied fungicides affect their use

narrow spectrum fungicides are used to control a specific pathogen while broad spectrum control a wide range

describe how natural enemies impact pest pop projections

natural enemies prey on a given pest pop, reducing the pop--projections can be overestimated if nat. enemies is not determined

ID flies (drone fly) characteristics

only two wings (halteres)--immature are maggots

define parts per million and parts per billion

parts per million (ppm)= one part in a million parts parts per billion (ppb)= one part in a billion parts can be on a weight or weight by volume basis

explain how cropping sequences influence pest mng decisions

past occurrence of a disease in a field may not determine which control methods should be applied before the disease occurs--crop rotations can control diseases or insects

explain how pest ID, stage and level affect pesticide selection

pest ID, stage and level are used to develop a treatment program--the effectiveness of pesticides will vary with these factors, among others

oral and posted warning requirements

pesticide labels will state whether oral, written or both are required

define pesticide residue tolerance in the current crop and future crops

pesticide residue tolerance relates to what yields can be expected when some damage to the current crop from pesticide residue occurs--if it will carry over, then a resistant crop should be planted

ID pesticide phytotoxicity damage to crops

pesticides can damage non-target crops or plants--the injury usually has a pattern in the field similar to application methods--damage to crop provides clues to the pesticide involved

explain how the presence of endangered species or species at risk affect pesticide selection and application

pesticides should be selected and applied to minimize damage to endangered species or species at risk--info on the label and knowledge of off-target species in the application area are used to make these decisions

explain how persistence affects pesticide selection

pesticides that are not persistent beyond the period necessary for control are preferred

explain how selectivity affects pesticide selection

pesticides that are very effective on specific target organisms may be preferred in that beneficial organisms are spared

explain how phytotoxicity to crop affects pesticide selection

pesticides that cause losses in yield or crop quality are poor choices compared to those that do not--in some cases variety selection can be used to minimize this effect

describe how water pH affects the efficacy of water-applied pesticides

pesticides usually perform best within a given pH range--outside the range, pesticide chemistry changes and the pesticides may precipitate from the water

explain how toxicity to non-target organisms affect pesticide selection

pesticides with lower mammalian or non-target toxicity applied at lower rates are preferred to reduce hazards to human health

explain how env. hazards affect pesticide selection

pesticides with small probabilities of env. hazard such as harming wildlife, non-target species are preferred

explain how temp affects a pest pop development

pests grow and development in response to temp--each organism will have a minimum, max and optimum temp for growth and development which can change during a life cycle--insects grow and develop in response to degree days

type of mouthparts for insects

piercing-sucking (long, needle-like) or biting/chewing (short, curved, toothed)

ID moisture extremes to crops

plant growth and yield are determined when drought occurs--low moisture over a sufficient time causes plant cells to lose turgor pressure and wilt permanently--standing water limited oxygen in the root zone--the damaged plants are susceptible to secondary infections

explain how planting date affects plant mng decisions

planting date and method can be changed so the development of the disease or insects and presence of the host do not coincide--planting the crop in time to outcompete the weed pop is also done

define point surface pollution

point surfaces of pesticides enter the env. from a specific, known containment--usually the volume of water containing the pesticide is unknown--a pipe or tank is a point source

ID true bugs (seed bug)

posterior portion of wings are membranous--immatures are nymphs

describe how prevention constructs an effective IPM program

prevention stops a pest from being introduced to a location--regulations and quarantines are common to prevent introduction--if a pest is in an area eradication is used to prevent the pest from remaining in the area--total pop can be eradicated, or disturbing the life cycle--ag practices can be changed to eliminate pest hosts

list procedures for responding to an accidental pesticide spill

procedures: -control the spill, make sure the source has been identified and stopped -contain the spill--use a dike in the sand or soil -clean up the spill, use absorbent material (soil, kitty litter) and put used material into a leak-proof container -call the appropriate governmental authority to report the spill

describe how pre vs post infection affects fungicide use

protectant fungicides are designed to prevent infection and are applied prior to the pathogen infection--curative or eradicate fungicides are applied after infection occurs, contacting the disease-causing organism and killing it or retarding its growth and repro

describe how to obtain, prepare and ship soil for nematode analysis

sample soil to plow layer--there is a lot of spatial variability in nematode populations, so fields sampled should not be much bigger than 50 acres--there are specific dates to sample for some nematodes to improve the idea of actual pop. soil samples should be placed in plastic bag, and sealed--so not let the soil from drying out and protect the bag from sunlight, heat or freezing-best stored in fridge and ship within a day or two

describe how clumped pest distribution pattern affects monitoring/mng

samples should be taken at random to increase the possibility of sampling areas where high pops exist

describe methods used to minimize introducing pests into fields

sanitation is used to decrease or eliminate disease inoculum and insect, and to prevent the spread of these pests--crop residue mng and keeping equipment clean--weed free seed is important in preventing new weeds

use shape, color and size of seed to ID weeds

seed characteristics are an excellent means of ID where these features are visible

describe how seed dormancy of weeds affects the competitive ability of weed populations

seed dormancy ensures that the weed will survive in the field for years allowing it to appear at competitive levels when the dormancy is broken

describe how seed vs soil vs foliar applied fungicides affect their use

seed treatments are for the disinfection, or protection of seed and seedlings--they are applied directly to the seed prior to planting--soil treatments are applied by injection or incorporation while tilling or planting to disinfect the soil of pathogens--foliar treatments are applied to aerial plant parts prior to the major development of disease and suppress the level of disease

explain how enviornmental risks affects pesticide selection

should be minimized during application

ID rain, hail and ice damage to crops

snow, hail and ice can physically break plant parts due to weight or impact on plant branches or growing points--rain can increase possibility of lodging

explain how soil characteristics and conditions affect pest pop growth and development

soil physical properties (moisture, temp, and aeration) can be particularly important in the growth of some insects

how do soil weather and crop condition affect pest mng decisions

soils can be altered to control pests (tillage)--weather patterns determine the extent and activity of pests--crop condition influences the impact the pest will have on the crop and potential for pest to invade crop

describe how water hardness affects the efficacy of water-applied pesticides

some pesticides can bind with ions in the hard water (Ca, Mg, Fe) reducing pesticide concentration as precipitates are formed--binding with these ions can also reduce pesticide entry into the plant

explain how water sources affect pest mng decisions

some pests will not withstand long periods of desiccation (fallowing during a dry period) or long periods without oxygen(flood)--irrigation can be used to improve plant growth and disease resistance

explain how row spacing and plant pop affects plant mng decisions

spacing plants sufficiently far apart can reduce humidity in the canopy that is needed for disease development--plant pop and row spacing affect competition with weeds for light, water...--narrow rows tend to favor insect and weed control, but enhance disease occurance

evaluating control options step of IPM

specific management practices that should be assessed: site selection, crop rotation, planting strats, fert, variety planted, use of growth regulators, harvest, crop residue mng, use of pesticides

explain how temperature inversion affects spray drift

spray drift can occur even in calm conditions when a temperature inversion (cold-hot-cold) keeps spray droplet suspended in the air

list how spray adjuvants affect pesticide coverage

spray droplet retention is improved by surfactants that increase wetting and spreading of the droplets on the leaf as well as by sticker that cause the droplet to be retained on the leaf or not easily removed by rain

recommend insecticide timing and placement based on stomach poison activity

stomach poisons are ingested by the insect--placement and timing must coincide with insect feeding

describe how suppression constructs and effective IPM program

suppression is used to reduce pest populations below the economic threshold if prevention and avoidance tactics have failed--chemical, bio and cultural and other tactics are used which minimize environmental impacts

nematode survival, movement from fields and infections

survival: eggs in soil, roots, larve in seeds movement: dispersal by water, animal, machinery infection: invade plant tissue through the cells (intracellular) and in between cells (intercellular)

virus survival, movement from fields and infection

survival: in living tissue, insects and nematodes movement: dispersal by insects or humans infection: invade plant tissue through the cells (intracellular)

uniform pest pattern sampling

systematic samples are taken where the population is uniform--prescribed pattern can be established--usually less expensive than random sampling

describe how contact vs systemic vs locally systemic affect fungicide

systemic fungicides are absorbed by the plant and distributed internally preventing infection or killing the pathogen inside the plant--locally systemic move into the leaf, but not other plant parts--contact fungicides are applied to the plant surface and absorbed directly by the pathogen--they prevent infection from occurring

recommend insecticide timing and placement based on systemic activity

systemic insecticides are absorbed by a plant or animal--when the insect feeds on the plant, the systemic insecticide enters the insect's guts

define pesticide residue levels in the soil

the concentration of pesticide in soil

explain how developmental time and seasonal period of activity of insects influences their ability to cause disease

the developmental time and period of activity are related to factors such as temp, light and food supply--upper or lower temps are present and at which activity slows or they are killed--when developmental time and period of activity of the insect coincide with the growth of the host crop, damage may occur

boarder effect pest distribution

the edge of the field should be sampled and the depth of the edge effect determined in addition to the overall pop

how does fertility level affect pest mng decisions

the fert program can directly or indirectly affect a pest: direct effects are influencing pest pop and vigor--indirect affects relate to the impact of the fertility program on pest hosts

describe how temp and moisture affect pathogens that are soil borne, residue borne and found in or on live plants

the impact of temp and moisture is dependent on the path and target plant--there is an optimum temp range for both pathogen activity and plant growth--temp extremes can help path levels but can also harm the plants--drought can increase pathogen activity since the plant is more stressed

explain how mode of action affects pesticide selection

the mode of action is the way a pesticide kills or damages a pest--using the same MOA can develop resistance

determining need for control step of IPM

the need for treatment is assessed by comparing the cost of treatment with the economic benefit of treatment--the EIL is the point at which those costs and benefits are equal--the economic threshold is the point where pest control will prevent EIL

explain how application method affects pesticide selection

the pesticide formulation, carrier and associated characteristics are considered when selecting application method--applications which place the chemical near non-target species or increase the change of drift/volatilization increase the risks of damage

discuss the importance of reading and following pesticide label instructions

the pesticide label contains important safety, env. hazard and application info--safe practices should be implemented, the environment should be protected and proper application procedures followed

explain how label restrictions affects pesticide selection

the pesticide must be labeled for the crop and rotation--pesticides not labeled for a crop can be used in a state if the government allows

explain how economic affect pesticide selection

the pesticide should provide an economic benefit greater than the cost of the pesticide use--treatments should be made at ET or before the EIL occurs

explain how host plants affect pop development

the present of host plants increases the possibility of increased pest populations

explain how site of action affects pesticide selection

the target of a pesticide is a protein (site of action) which is inhibited disrupting pest development and killing the pest

explain how overwintering and over summering strategies affect insects

these are stages where insects can survive winter or summer conditions to complete their life cycle--these are governed by day length and temp to assure that the insect will survive

describe how light, temp, moisture and humidity affect the competitive ability of weeds

these factors affect the growth and development of weeds and crop plants--if a particular combo favors the weed over the crop, then weed survival is increased

recommend insecticide timing and placement based on ovicidal activity

these kill insect eggs and so must contact the eggs which dictates placement and timing of the application

define non-point source pollution

these sources of pesticides enter the environment form an area that is not well defined--usually the volume of water containing the pesticide is difficult to estimate--a farm field or city neighborhood would be a non-point source of pollution

explain how chemical and physical properties affect pesticide selection

they make the pesticide effective and minimize env. contamination--solubility, stability and volatility are examples

list pesticide modes of entry into the human system

through skin, mouth, lungs, and eyes

explain how tillage affects pest mng decisions

tillage, burning canb be used to destroy pathogens on crop residues--can be used as mechanical weed control--changes insect habitats

explain how existing or potential pesticide resistance affects pesticide selection

to avoid resistance to pesticides, it is important to avoid using high rates of a single pesticide as well as its continued use with same MOA

explain how equipment affects pest pop growth

tractors and equipment can transport pests to other locations

use stem shape to ID weeds/ reproductive structures

tuber: enlarged underground stem that has nodes (potato) rhizome: underground stem that can have buds that sprout forming new shoots stolon: above ground stem with buds that sprout forming new shoots bulb: underground stem with fleshy leaves that store food corm: fleshy underground stem with papery leaves grass stems are round or flattened--broadleaf stems are erect, twisted or growing along ground

list possible chronic effects of pesticide poisoning

turmors (cancer), mutations, neurological effects (loss of memory, headaches, muscle loss)

describe proper procedures for disposing of pesticides and pesticide containers

unused pesticides mixture should be removed and contained for proper disposal--containers should be triple rinsed and rinse should be put back in sprayer

personal protective equipment

use of protective clothing may include: hat, gloves, goggles, long sleeved shirt, pants-- after use rinse in clean water then wash in hot water using detergent--repeat washing if pesticide color or oder is still present--dry outside

explain how field history affects pesticide selection

used to ID types of pests and estimate the pop of those pests that might need to be controlled

explain why supporting info is important when submitting a sample to a lab

useful in determining the nature of the pest or pest control problem

recognize symptoms of acute pesticide poisoning

usually occur within 12 hours of exposure- -mild: headache, dizziness, blurred vision moderate: unable to walk, weakness, muscle twitches, chest discomfort severe: unconsciousness, muscle twitches, breathing difficulty, death

explain how initial pest pop affects its development

usually, the higher the initial pest pop the higher the potential increase for pest pop--the initial pop is increased by the dispersion of insects, their birth rates, the pattern of insect growth and the age of the insect population--but higher initial pop may not lead to higher pop total

explain how variety selection affects pest mng decisions

varieties can be selected that offer resistance to certain pests (diseases, nematodes), posses genes that are biological pesticides, posses genes that impart pesticide resistance (weeds) and are competitive if pest are present

explain how weather conditions affect pesticide selection

weather and soil properties (ph, rainfall, soil moisture and temp) affect the efficacy of pesticides--air temp and wind can stimulate drift and volatilization

use info about pest history to make pest mng decisions

weed persistence in the field is enhanced by high seed production, germ rates and long seed survival--some weeds enhance competitiveness via allelopathy--thus a history of weed populations is useful--history is not usually a good predictor of future disease outbreaks

describe how physical characteristics of weeds increases competitive ability of weeds

weed seeds may be in specialized structures that allow dispersion by wind, water and animals increasing the pot. for survival

how does crop biotech traits affect pest mng decisions

weeds and insects can be controlled with biotech--crops with tolerance to a specific herbicide can be used in a herbicide program

describe how reproduction method of weeds affects the competitive ability of weeds

weeds reproduce by seed and vegetative parts--seed viability, seed dormancy and seed numbers are important for weeds that produce seeds--vegetative structures are important for perennial weeds (stolons, rhizomes, bulbs, aerial bulblet, tubers--these asexual growing parts are difficult to control cultural

describe how life cycle of a weed increases the competitive ability of the weeds

weeds that germinate before crops 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 (ie producing viable seed)

explain how to use time of year to help ID a pest

weeds, diseases, and insects have life cycles which vary over the year--each of these pests is active during some months and can be inactive during other months

describe how chemical compatibility affects the efficacy of water applied pesticides

while tank mixes of pesticides are more often economical and time-saving, some pesticides should not be mixed together or should only be mixed in a certain order--sometimes mixtures can provide more efficacious mixtures than than alone--foaming and formation of sludge on the tank bottom can also be a problem--some mixes are illegal

ID sandblasting damage to crops

wind can carry sand particles that can damage plant tissues

ID plant damages caused by wind lodging

wind causes plant injury by causing plant parts to rub or break

explain how wind affects pest pop growth and development

wind transports insects to new locations for infestation--wind damage to new plants can be mis-ID'ed as insect damage

ID thrip characteristics

wings are featherlike, tarsi have no claws--immature are larvae

wing characteristics of insects

wings can be present or absent and vary in size, color, shape and thickness

ID leafhopper characteristics

wings held in roof-like position, usually move sideways--immatures look like adults, but are smaller and do not have wings

emergency assistance requirements

worker employers must provide emergency assistance to workers and handlers in their area that have been poisoned or injured by a pesticide--they must provide emergency transportation...


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