Agronomy Written Test Questions PART 1 Comprehensive Questions and Answers 100% Accuracy

Who is given credit for discovering that soybeans were an excellent source of protein and oil and for encouraging farmers to rotate their crops with soybeans? - ANS George Washington Carver What term is used to describe fine brown or gray hairs on the leaves, stems, and pods of soybeans? - ANS pubescence Which of the following is a true statement regarding soybeans? - ANS Soybeans are generally considered a source of complete protein. The top 2 states in terms of soybean production? - ANS Iowa and Illinois A (n) _________ is a plant that can fix nitrogen from the air in the soil - ANS legume Living organisms that cause disease are often referred to as ______. - ANS pathogens Which of the following is a benefit of integrated pest management? - ANS reduced pesticide costs Economic injury level is _____. - ANS the point at which the cost of pest control equals the revenue loss caused by a pest Which method of pest control involves making the crop environment unsuitable for pests to feed, live, or reproduce? - ANS cultural What are used to kill unwanted plants? - ANS herbicides What is caused by environmental imbalances and cannot be spread to other plants? - ANS noninfectious disease What are the three components of the disease triangle? - ANS a susceptible host, a causal agent, and environmental conditions What are the principle causes of most diseases that affect agricultural crops? - ANS Fungi Which of the following is a cultural/physical method used to manage pest populations? - ANS removing and destroying infected plants What is a pathogen? - ANS a living, disease-producing agent Optimum care of plants through irrigation and fertilization reduce weed, disease, and insect problems. Which type of disease control measure do these represent? - ANS cultural Use of beneficial predatory insects is an example of which type of pest control? - ANS biological Why is the implementation of an IPM program beneficial to the environment? - ANS There is reduced contamination and degradation of soil and water. A grower notices that a crop displays yellow streaking and stunted growth and identifies the problem as virus-related. How would this type of disturbance be classified? - ANS infectious diseaseinfectious disease What is a tiny, hair-like roundworm that feeds on the roots of plants? - ANS nematode What is a main objective of cultural control of plant pests? - ANS maintaining healthy plants by providing optimal growing conditions What is the first step in choosing an insecticide for pest control? - ANS properly identify the pest What is a nonselective herbicide? - ANS one that will kill any plant with which it comes in contact __________________ are absorbed by the roots or other plant parts and moved throughout the plant by vascular tissues - ANS Translocated herbicides Dicot plant weeds including dandelions, ground ivy, plantain, and spurge are called __________. - ANS broadleaf weeds What describes biological weed control? - ANS control uses insects, diseases, predators, or other plants that are harmful to weeds without causing damage to crops What type of weed is injurious to crops, people, or livestock? - ANS noxious What type of pesticide is used to kill unwanted plants? - ANS herbicides A farmer wants to eliminate ragweed and pigweed that are competing with corn in a field. What type of herbicide should she use? - ANS a selective herbicide What classification of herbicides is applied before the weeds and/or crop emerges, but after the crop has been seeded? - ANS preemergent herbicides What refers to how herbicides kill weeds, such as, seedling growth inhibitors and photosynthesis inhibitors? - ANS mode of action What is the most effective herbicide to use on stubborn perennial weeds such as Canadian thistle that have extensive rhizomes from which new shoots emerge? - ANS systemic Annual grasses and small-seeded broadleaf weeds can be controlled in sunflower crops by applying the herbicide before the sunflower is seeded. How would this treatment be classified? - ANS pre-plant How do annual weeds reproduce? - ANS sexually Why do contact herbicides have limited effectiveness on perennial weeds with underground storage organs? - ANS They only kill the plant tissue with which they come in contact. Unclean crop seed may contain weed seed and may be planted along with the crop seed. How is this process categorized? - ANS artificial weed dispersal What is the best reason why weeds are controlled in agricultural fields? - ANS Weed populations compete with crops or pasture for water, nutrients, light, and space. Nymphs are associated with ____________. - ANS incomplete metamorphosis What type of mouthparts do insects that cut, tear, crush, and chomp leaves, stems, roots, flowers, and fruit have? - ANS Chewing What type of insect management is accomplished with the physical removal or exclusion of insect pests? - ANS mechanical Which family of insecticides includes plant toxins such as, caffeine, nicotine, pyrethrum, and rotenone and bacterial diseases including Bacillus thuringiensis? - ANS biologicals How does a contact insecticide enter an insect's body? - ANS It is absorbed through the exterior of an insect Why would a vegetable grower want to avoid using a systemic pesticide? - ANS The pesticide could find its way into the plant organs that are eaten. How does a fumigant insecticide enter an insect's body? - ANS It enters the respiratory system of the insect. An agronomist has identified evidence of insects devouring the leaves of a crop. What would be the most effective means of control? - ANS a stomach insecticide What provides protection and support for the insect? - ANS exoskeleton The corn earworm is the most destructive insect pest of corn in the United States. Which stage of the insect's metamorphosis causes the most damage? - ANS larva An insect, such as the grasshopper, undergoes incomplete metamorphosis. What process allows the insect to continually grow to reach a mature size? - ANS molting Why is an insect pest's feeding habit important? - ANS It can determine the best method of control. Which method of insect control is the most likely to cause environmental damage? - ANS chemical Which group of insecticides including DDT and dicofol are highly toxic and are very dangerous because they are absorbed by the fatty tissue of animals? - ANS organochloride A grower faced a situation where a pest appeared to be eliminated from a field, and after a few weeks the pest repopulated the field. What is the best explanation for how this occurred? - ANS pest resurgence What is a pathogen? - ANS a living, disease-producing agent What are the most common causes of infectious plant diseases? - ANS fungi A _________ is an organism that benefits from a prolonged association with another organism or host. - ANS parasite How is the incubation phase of plant disease progression defined? - ANS a period during which the pathogen develops a form that can penetrate or infect the new host plant A susceptible host plant, a disease-producing agent, and a favorable environment are associated with _______. - ANS the disease triangle What is caused by environmental imbalances and cannot be spread to other plants? - ANS noninfectious disease What is a career title for a professional who specializes in plant health and agents that cause plant diseases? - ANS plant pathologist The disease triangle consists of _____. - ANS a susceptible host, a causal agent, and environmental conditions What is the best explanation as to why the leaves on a plant would wilt and turn brown, individual branches die back, and the vascular tissue appear discolored? - ANS The plant has a fungi infection of the xylem and phloem. Which of the following is a cultural/physical method used to manage pest populations? - ANS removing and destroying infected plants A heavy rainfall causes flooding of a field. Within a week the crop shows symptoms of disease including the yellowing of leaves. How would this type of disturbance be classified? - ANS abiotic disease How do nematodes affect plants? - ANS They reduce plant vigor and growth. Plant diseases progress by five distinct phases; what is the correct sequence? - ANS inoculation, incubation, penetration, infection, and disease Some pathogens may infect certain plant parts. How is this type of infection classified? - ANS localized infection What are eukaryotic organisms that cause disease; most reproduce by spores? - ANS fungi Which of the following is a true statement regarding bacterial diseases? - ANS Healthy plants are less disposed to bacterial disease. A __________ is a localized diseased area or lesion that is discolored. - ANS canker What are organisms that can live only on nonliving matter? - ANS obligate saprophytes What is a fungal disease that causes lesions on the roots or stem of seedlings that weaken the stem, causing it to topple? - ANS damping off What is a common viral disease that causes symptoms include stunting, mottling, and curling of leaves? - ANS soybean mosaic When are fungicides most effective? - ANS when applied before fungal disease is present Which of the following statements is true? - ANS A relatively small number of bacteria cause disease to living plants Why is it important to provide plants with optimal growing conditions? - ANS Healthy plants are less susceptible to disease.)Healthy plants are less susceptible to disease. How does fireblight damage of apples, pears, and related plants? - ANS Flowers and leaves turn brown and wilt, shrivel, and blacken. How would the quick death to living tissue, rot, and canker be classified? - ANS necrosis Corn smut is an obligate parasite. What does this mean? - ANS It extracts nutrients from living plant tissues and survive apart from its host How are watering practices and rainfall associated with plant diseases? - ANS Water can spread disease organisms and moisture aids growth of microbes. What is one of the most economically damaging plant-parasitic nematodes due to wide distribution and numerous host plants? - ANS root knot nematode In terms of disease management, what is the greatest advantage to managing insect vectors, removing perennial host plants, and sanitizing tools? - ANS The spread of disease is reduced. What would you expect a scouting trip through a field to reveal? - ANS the pest infestation status What is the preparation of large or soft-bodied insects so they will not decay? - ANS fixing What should be made for each field to indicate the location of various weed species? - ANS a weed map Which method of scouting for insects involves visual clues, pheromones, or food odors? - ANS Using traps How should plant diseases be identified correctly? - ANS The symptoms of the disease and the signs of the pathogen itself must be carefully observed. From what parts of the field should samples be collected in a crop scouting program? - ANS from random spots How often is it recommended to visit a field for crop scouting purposes? - ANS at least once a week Which distribution pattern would be expected for European corn borers, corn rootworm adults, corn leaf aphids, and foliar diseases? - ANS Pattern I: Pests are expected to be uniformly spread over the field. Why is the correct identification of insect pests important? - ANS It determines control measures to be taken. Which is true when collecting plant samples for disease identification in a testing laboratory?Which is true when collecting plant samples for disease identification in a testing laboratory? - ANS Submit fresh representative plant samples. Insect pests can be monitored by estimated crop damage. How is estimated crop damage usually expressed? - ANS as a percentage Leaf or flower blights, leaf spots, root rots, cankers, or wilting are attributed to _____. - ANS pathogens What should a sample for the identification of nematodes include? - ANS soil and feeder roots Why is crop scouting important? - ANS It can determine whether a control measure is needed The absorption of pesticides through the nose and respiratory system is _____ - ANS inhalation exposure Which of the following indicates the lowest inhalation toxicity? - ANS .C50, 500 Blowing out a plugged nozzle or eating without washing contaminated hands can result in ________. - ANS oral exposure What refers to the degree of poison in a material? - ANS toxicity What are widely sold and are relatively safe as long as label instructions are followed? - ANS General-use pesticides What term refers to clothing such as rubber gloves, goggles, a respirator, and other defensive gear? - ANS personal protective equipment Rubber gloves and aprons protect a pesticide applicator from _____ exposure? - ANS dermal A grower has a choice between two pesticides that are both labeled for use against a particular pest. Pesticide A has a LD50 of 100, and pesticide B has a LD50 of 300. What can he conclude? - ANS Pesticide A is more poisonous than pesticide B. How should empty pesticide containers be handled? - ANS Triple rinse the containers and puncture them. A forester mixed chemical pesticides and applied them to a tree using recommended procedures. Afterwards, he used the bathroom, and then washed his hands. The route of entry of pesticides into his body would most likely occur through _____ exposure. - ANS dermal How do general-use or restricted-use pesticides compare? - ANS Restricted-use pesticides have higher toxicity levels and are more hazardous than general-use pesticides. What is the physical movement of pesticide droplets or particles through the air at the time of application or soon after? - ANS drift Which is a safety practice to follow when using pesticides? - ANS Use pesticides only approved for the crop and disease or pest What is the method used to measure inhalation toxicity? - ANS LC50 What is the primary purpose of the pesticide label? - ANS to provide information about the active ingredient Dry flowables, solutions, and dusts are examples of _____. - ANS formulations What are surfactants? - ANS wetting agents that lower the surface tension of a liquid and allow easier spreading of the pesticide What are words that are required on every label to indicate the degree of toxicity and the potential danger of using each pesticide? - ANS signal words What is the most important practice when working with pesticides? - ANS reading the label Which part of a pesticide label helps users decide the proper steps to take to protect the user, others, and domesticated animals that may be exposed? - ANS precautionary statements Why would an applicator add surfactants when mixing pesticides? - ANS to allow easier spreading of the pesticide What is printed on the label of all pesticide containers? - ANS keep out of reach of children Where would an applicator look to determine the pesticide's formulation? - ANS on the front panel Roundup® made by Monsanto is also known as glyphosate. What type of name is glyphosate? - ANS common name Why is the name and address of manufacturer printed on a pesticide label? - ANS so that the company can be reached in case of an emergency Which section of a pesticide label includes specific guidelines such as application rates and reentry limitations? - ANS Directions for Use What is the function of the active ingredient in a pesticide? - ANS to kill the pest or pathogen A pesticide user sees the letters (EC), (WP), (DF), (S), (G), and (D) on various pesticide products. What do these letters represent? - ANS formulations With which government entity do manufacturers register pesticides? - ANS Environmental Protection Agency What is an application made before the crop has emerged or broken through the soil surface? - ANS preemergence What type of application involves treating only selected plants? - ANS directed What must be done to the pressure to double the flow rate? - ANS The pressure must be increased four times What would happen if the ground speed of the sprayer is doubled? - ANS The application rate is reduced by one-half What happens if the effective spray width per nozzle is doubled? - ANS It decreases the gallons per acre applied by one-half. What type of application used primarily with fruit trees and ornamentals involves treating only selected plants? - ANS directed What would happen if the ground speed of a sprayer is increased from 3 miles per hour to 6 miles per hour? - ANS The application rate is reduced by one-half. A park maintenance worker wants to double the flow rate of a nozzle from 0.25 GPM at 15 psi to 0.50 GPM. How would she change the pressure to double the flow rate? - ANS increase it to 60 psi A farm manager calibrates a sprayer to deliver 30 GPA (gallons per acre) at 4 MPH. However, the operator assigned to the task travels at 6 MPH (the pressure remains constant). What is the result? - ANS The application rate falls to 20 gallons per acre. A lawn maintenance company promotes its weed control program. What is the type of application in terms of timing? - ANS postemergence A vegetable grower applies herbicides in narrow strips usually 10 to 12 inches wide. What is this type of application? - ANS band How can a grower increase nozzle flow rate? - ANS Use of a nozzle tip with a larger orifice or increase the pressure in the tank. Which type of application is least likely to cause damage to the environment? - ANS spot A farmer scouting his field notes that weeds have reached the injury threshold throughout the entire corn field. What type of herbicide application would be his best choice? - ANS broadcast What is setting equipment to meter the exact amount of herbicide needed? - ANS calibration What is the most common cause of pesticides reaching a nontarget area? - ANS drift _________ indicates the amount of time it takes for a pesticide to biodegrade or break down. - ANS Pesticide persistence Which of the following poses the greatest threat to the environment? - ANS accumulative pesticides Which of the following is the best definition for rapid decomposers? - ANS Pesticides that break down quickly and remain on the target area or in the environment only a short time before being changed into harmless products. What does the recommended disposal procedure of empty pesticide containers involve? - ANS Triple rinse the container and puncture. How do pesticides contaminate ground water? - ANS by leaching Why are biodegradable pesticides the preferred type of pesticides?Why are biodegradable pesticides the preferred type of pesticides? - ANS They are less likely to accumulate in soil, groundwater, plants, or animals. When America adopted the bald eagle as the national symbol in 1782, it is estimated that the country was home to 100,000 nesting eagles. By 1963, only 487 nesting pairs of bald eagles