Abiotic Quiz's questions

From the selections below, select the answer that is abiotic.

Excessive organic matter

Parasitic plants

Fungi

Nematodes

excessive organic matter

From the list below, select the best answer that list a possible abiotic cause of a plant disorder.  

The presence of nematodes in the soil.

The presence of a virus in the plant.

Slime trail from a slug.

Excavator cutting too close to a tree while removing soil and chopping tree roots.

Excavator cutting too close to a tree while removing soil and chopping tree roots.

The reason growers should conduct a base saturation analysis of their soil is to enable them to make quick changes to the soil nutrition and structure.

True

False

False

Based on our lecture and the comparison of EC levels of irrigation water on assorted crops and their yields, select the most correct answer.

All of these answers are correct

None of these answers are correct

Plant species have different levels of tolerance (as defined by potential yield) to salinity levels.

All plant species suffer (as expressed by reduced yield) at an EC level of 2.0

All crops may display symptoms of salinity stress, marginal leaf burn for example, but will not have a reduced yield.

Plant species have different levels of tolerance (as defined by potential yield) to salinity levels.

A symptom is a plant's response to either biotic or abiotic causes.

True

False

True

Fill in the blanks with the best answers as discussed in lecture for the purpose of this course.

Traits of a good diagnostician includes in-depth knowledge of ____. A good diagnostician should have access to_____. Finally, a good diagnostician should have personal traits of_____

Make sure to use words or phrases only from the following list.

plant nutrition deficiency symptoms

plant species and biology

environmental conditions

soil testing lab

diagnostic resources

being observant

intellectual curiosity and logical thinking

plant species and biology, diagnostic resources

intellectual curiosity and logical thinking

Fill in the blanks only using one of the choices listed.

The genetic potential yield of a crop can only be___by stressors.  

reduced

increased

changed

reduced

You notice that in a field of corn, that one row seems to be stunted and not growing as well as the other rows.  This is most likely to be caused by a biotic disorder.

True

False

False

A symptom is always a sign.

True

False

False

One of salinity tests discussed in lecture is the PourThru method developed by North Carolina State University and this test has the benefit of being nondestructive.

True

False

True

Necrotic leaf margin

Centipedes in the potting media of a plant

Powdery mildew conidii

Aphid on a leaf

symptom, sign, sign, sign

You are looking at a field with a terrain consisting of small rolling hills with a crop of potatoes.  You can clearly see that in all of the low spots in the field that the potato plants exhibit chlorosis.  This is an example of an abiotic disorder.

True

False

True

From the selections below, what is the most important reason that we as diagnosticians use common tests such as tissue test, water and soil test, leaf pressure, etc.?

To keep track of the effectiveness of fertilizer and pesticide applications.

To evaluate if the genetics of the plant are causing the disorder

To track trends and prevent potential crop problems

As it's required by the USDA for all consumable crops on a bimonthly basis.

To track trends and prevent potential crop problems

A sign is always a symptom.

True

False

True

Deficiency symptoms for mobile nutrients only show up in the new growth.

True

False

False

You have run a pH test on your soil and find out that it is too alkaline.  Which amendment will reduce the pH of the soil?

lime

sulfate

sulfur

gypsum

dolomite

sulfur

What best describes essential nutrients that are considered mobile in the plant.  do not include 'somewhat mobile' in this list.

Nitrogen, Potassium, Chlorine, Nickel

Low pH levels in soils can result in toxicity levels of some minor essential elements.

True

False

True

Based on the picture, what is the most likely nutrient deficient in this lettuce?

Calcium deficiency as the new growth is impacted.

Plants need the same concentration of essential elements throughout their crop cycle.

True

False

False

In lecture, several essential nutrients were classified as being dependent on the water transpiration stream.  This means that during long periods of cool, dark, and windless weather, (foggy days) it may be possible to develop deficiencies with these specific nutrients even though soil tests indicate there is sufficient quantities present and available for plants.

True

False

True

If the pH of your soil measures 7.4, which nutrient could become deficient because of high pH?

Iron

Calcium

Molybdenum

Sulfur

Iron

What can raise the pH of the soil?

agriculture lime

All plants grow best in the pH range of 5.8 to 6.4 as that provides the maximum availability of all nutrients.

True

False

False

My favorite analogy, Justus Von Liegig's 'Law of Minimum', shows a barrel with many staves or slats.  This analogy refers to that plants will be limited in their potential yield by the lowest 'stave' in the barrel.  These staves refer to all aspects of growing, including, nutrient levels, light levels, carbon dioxide levels, ideal moisture level in the soil, etc. 

True

False

True

This minor element shows stark interveinal chlorosis in the youngest leaves

One of easiest nutrients to visually confirm by mature leaves turning a pale green

On more mature leaves, symptoms start with yellowing, followed by browning/tanning/ or bronzing colors, followed by small necrotic spots, followed by small-sized fruit

At high pH levels, Calcium can compete with ?

One minor element that we are more likely to see as a toxicity problem than a deficiency problem is

This nutrient deficiency is exhibited by 'little-leaf' new growth

Iron, Nitrogen, Potassium, Magnesium, Copper, Zinc

You have been asked to come in as an expert to a citrus orchard where there is obvious interveinal chlorosis of new growth.  The manager shows you a tissue analysis where it shows that iron is deficient.  What are your recommendations to correct this problem?

pH sample, if high pH add sulfur or peat moss

There can be many issues involving visually diagnosis of nutrient deficiencies. From the list below, select the one statement that is incorrect.

All symptoms are specific for each nutrient so all deficiencies can be visually diagnosed easily.

Plants may have a deficiency but not yet show any symptoms, (hidden hunger).

Field symptoms of deficiencies (out in the field) may appear different from 'ideal' symptoms.

Other stressors can cause symptoms similar to nutrient deficiency symptoms.

All symptoms are specific for each nutrient so all deficiencies can be visually diagnosed easily.

All nutrient deficiencies determined through tissue testing can be resolved by adding the deficient nutrient to the soil.

True

False

False

As you are learning, there are many different symptoms for plant disorders with some symptoms being similar for different disorders.  Select the symptoms that would indicate leaf scorch disorder in a plant.

Leaf rolling or curling

Tips of new leaves showing necrosis especially on those directly exposed to the sun

Wilting of young shoots

Tips of recently matured leaves showing necrosis especially of those directly exposed to the sun

Tips of recently matured leaves showing necrosis especially of those directly exposed to the sun

s a consultant to a farmer whose land is showing high salinity, you can offer solutions.  From the list below, select the one incorrect solution.

Grow an alternate crop that is more tolerant of salinity

Make sure to have leachate during every irrigation event

Apply gypsum to reduce sodium levels

Apply dolomite to reduce the sodium concentration in the soil

Apply dolomite to reduce the sodium concentration in the soil

Leaf scorch is one disorder we studied.  List two environmental conditions that are most likely to result in leaf scorch and list 4 things that would increase the likelihood of leaf scorch.  Please provide a numbered list instead of writing out a paragraph.

high temperatures, high sun intensity, low relative humidity, high winds, increase the likelihood? Lack of moisture in soil, reduced area of irrigation, small soil volume if in a pot, plant grown lush in the immediate past, plant moved from low light conditions to high light conditions. High salts in soil, poor drainage, insufficient roots.

Sunscald is a disorder that typically happens in winter but you may not see the symptoms until spring or summer.

True

False

True

he best way to treat bark on a tree trunk that is exhibiting sunscald damage is to wrap it with a protective coating such as plastic bark tape, so no further damage can occur.

True

False

False

If in field, some sections of a lettuce crop experiences a sustained waterlogging event, there isn't any options for the crop to recover from the damage and there will be a reduction in yield.

True

False

True

Etiolation is caused by

Photo-oxidative bleaching is caused by

Leafscorch is caused by

A continuous low light growing environment, Ultra-violet rays during high light intensity events, The inability of a plant to provide enough water through the transpiration stream to the foliage during high light events

Growers of hydroponically grown peppers found a higher incidence of pepper stip in single rows of peppers compared to double row of peppers due to the higher light impacting the peppers.

True

False

False

You purchased this pothos (pictured below) last year and put it into your room.  You have noticed that the plant is slowly losing its variegation and its new leaves are growing to a straight green color.   This disorder is called___ and is caused by ___

genetic reversion, low light

Match the disorder to the best conditions or symptoms for that disorder. 

Wilting leaves of plant when soil is moist

Shorter stems on flowers from bulbs

High light intensity combined with cool temperatures

Bark splitting and peeling away from trunk

High salinity in soil, Insufficient chill hours during dormancy, Photo-oxidative bleaching, Winter sunscald

A way to reduce possible freeze damage on trees is to ensure that the soil is dry in the root zone so that less ice crystals can form.

True

False

False

Select the best match for each statement

Helpful to reduce frost damage in orchards in winter

Something that should be avoided as that increases the chance of getting frost damage in fall with the first frosts

Important to prevent early and unseasonable flower bloom in orchard

sufficient moisture levels in soil, Late season application of nitrogen, Select the correct cultivar to match normal winter chilling hours

The only difference between photo-oxidative bleaching and either sunburn browning or sunburn necrosis is that photo-oxidative bleaching will only occur during high light, high temperature conditions, and the sunburns will only occur during high light and low temperature conditions.

True

False

False

Of the herbicides we looked at, which one is considered the most volatile?

Clomazone (Command)

Dicamba

Glyphosate (Round-Up)

2,4-D

Clomazone (Command)

omato plants are sensitive to ethylene and could be used as ____plants to detect if unit heaters are not properly combusting natural gas while heating the greenhouse by exhibiting specific symptoms common to ethylene exposure.

sentinel, indicator

Having a vegetative buffer between the application site and a waterway will help to reduce herbicide movement off-site that could lead to water contamination.

True

False

True

If a pesticide applicator was interested in reducing spray drift during an application, what can the applicator do?

Select the most correct answer.

Raise the spray boom

Increase the spray pressure

Drive the tractor slower

Increase the orifice size on the nozzle

Increase the orifice size on the nozzle

his picture of a soybean is exhibiting typical herbicide damage symptoms of which herbicide?

Dicamba

Command or clomazone

Glyphosate or Round-Up

2,4-D

Dicamba

The most critical factor for whether an herbicide will volatize and potentially cause vapor drift damage, is the vapor pressure of the chemical.

True

False

True

We discussed other herbicides and their symptoms of damage.  What herbicide can cause this kind of bleaching damage?

2,4-D

Dicamba

Clomazone (Command)

Captan 50

Clomazone (Command)

Crop injury due to active residual phytotoxic chemical agents previously applied and still present in the soil or substrate is called____

injury.

carryover

One of the pollution types we discussed is found as a natural component of soil.  Which is it?

Ethylene

Fluoride

PAN

Ozone

Fluoride

Choose the FALSE statement about Ozone (O3).

Sentinel crops such as bean and squash serve as Ozone presence indicators 

Ozone levels led to the abandonment of Euonymus propagation by root cuttings in LA county 

Ozone accounts for up to 90% of all observed plant injury attributable to air pollution 

Ozone damage decreases as light intensity increases 

Ozone damage decreases as light intensity increases 

What is TRUE about ethylene?

Ethylene can be both beneficial or harmful to plants depending on the circumstances.

Symptoms include epinasty.

All of the answers are true.

Source can be from incomplete combustion of natural gas.

All of the answers are true.

We discussed the problems that can be associated with Captan 50 fungicide applications.  Explain why this fungicide is so effective, how it works and what situations cause the phytotoxicity.  

its effective due to the fact that fungi don’t become resistant to it due to the fact that it blocks multiple biochemical pathways, toxic if penetrates leaf or fruit tissue,

Many environmental factors increase the likelihood of vapor drift of pesticides. From the list below, select the one answer that WOULD NOT increase this likelihood.

Low relative humidity

Hot temperatures

Bright and intense sunshine

Cold temperatures

Cold temperatures

From the choices below, select the condition that would decrease the chance that pesticide particles can drift (or move off-target) after application is completed.

Inversion layer during application

High volatility of the pesticide

A 6 mph wind

Rain event

A 6 mph wind

One symptom of accidental 2,4-D damage on grape plants is having a reduction in fruit size so that the clusters have large and very small berries in the same cluster.

True

False

True