Tenta frågor Flashcards
A1
Background: You are supposed to carry out an experiment
to test nutrient use efficency
(NUE) Of five spring-grown wheat cultivars. The overall objective is to evaluate breeding posibilitys for increased NUE of grain produktion. Before you do the experiment you need to carefully plan your study. Please answer the following question wich should help you to write an appropirate study plan (do ot include study plan in exam)
a) How do tou define NUE and its components in your study? Vilken crop characteristics will you measure? b) Please formulate at least one specific question and one specific hypotes for your study c) What will be an appropriate experiment desighn for your study? d) Vilka external factors do ypu belive will greatly affect your result
a) NUE is defined as grain production per unit of N available in the soil, I would measure the input and output of N and where the N is going in the plant.
b) Q: is there a different in NUE between the different cultivars? H: Their will be a deferens between the different cultivars.
c) Plant the different cultivars in separate pots and randomize the order (so there is no bias) let them grow under the same conditions. Later measure the N content in the leaf’s (SPUD gun) and the roots.
d) If the settings are too cold or too warm (we want good spring conditions if we are starting from a germinated seed). If the setting are flavourful the seeds might not germinate. To wet or to dry will also cause stress for the roots which will affect the result (rain can wash the nutrient away)
B1
a) The domestication process has resulted in major morphological an physiological differences between the crop and its wild ancestors. Interestingly there is increasing evidence that a speci´fic class og genes is controlling these differences. Explain function of these genes
b) Discuss which method you woud use
a) the rare genes that has been breed by humans is few but dominant, these are the ones that make sure the crop look the same and mature evenly throughout a field and has similar characteristic from year to year which makes the crop more reliable and profitable.
b) I would use a QTL, this method is used to locate traits that you are interested in (not genes because its really hard to locate the partial gene).
Question B2 (S. Chuanxin & A. Westerbergh - breeding) 6 points
Protein X in rice is a transcription factor and ils gene sequence has been published.
Overexpression ofthe gene in rice can increase starch synthesis and yield.
A recent QTL analysis revealed co-localiA1tions between a QTL for the protein X gene
expression and a QTL for starch synthesis and yield also in several other model plants.
a) Describe why a transcription factor gene is important in breeding. [1 pl
b) Describe how a GMO method can be used via modification Of the protein X gene
expression to increase starch synthesis and yield in rice (including description of a
transformation method). [l .5p]
c) Name a method that can be used to modify gene expression, but currently is not counted as
a method to generate GMO. [0.5p]
d) Describe how traditional and molecular marker based breeding can be used to increase
starch synthesis and yield in rice. [3p]
a) Because it has a hand in how much will be existing in the next generation (quantitative).
b) Sätta in fler gener och öka amplifiseringen av singnaleringen. Fler gener som kodar för gen X.
c) argobacterium: you move the gen you want to a ti plasmid, this will then be placed in a plant cell. Ti plasmid inserts the gene to the plant chromosome you then screen for the cell with the transgene and select it for breeding.
d) You look for the plants has a lot of TS and breed on the plants that has a lot.
Ouestion C1
One single plant of Chenopodium album, a weedy summer annual species, is capable of
producing 100 000 seeds and more
Thus, seeds from one plant would next year result in emergence of 100 000 seedlings, which
at the end ofthe season would produce 100 000 seeds each, whieh next year would result
in IO 000 000 000 seedlings, which would.
However, a more realistic figure for emergence would be 50—100 seedlings mo. Discuss the
difference between the theoretical scenario and a normal situation, and how different
factors and interactions can affect the population size in an agricultural field.
a) The theoretical scenario is without treats to the weed but in nature there is natural treats to the weed. The natural scenario is many things, say that the seeds drop in the autumn, then the seeds stand a risk off drying out by frost, in the spring there is still a risk of frost and drowning (early spring rain). A natural death count will happen during dormancy. If the seeds don’t germinate before the crop they can die by lack of sunlight/nutrition/moister. But it the weed manage to germinate before the crop they can probably die by herbicides. And if they manage to live through all that there are the pest/ disease/ predators which will kill a certain number of weeds.
C2
Many of the worlds worst agticultural weeds are closely related to the crop in which they constitute the largest problem (exempel I orginal)
A) in ehat way do the weeds benefit from the close resemblance with the crop
B) what are the most importand traits which distinguish the closly related weed from the crop?
a) The closer they are the harder they are to kill using herbicides. They have the same opportunity. Take wild oat in Sweden, there is no direct herbicide against it today due to the fact that you stand a risk of killing the oat with it. Some grass herbicide is far away enough to affect the weed negatively without hurting the crop but most farmers turn to removing the weed manually.
b) The nutritional value is one example.
C3
Describe the development and growth of shoots and rhizomes of couch grass from a pice of rhizome that was incorporated in the soil before sowing of winter wheat in a field outside Uppsala in sweeden until late the following host. Focus on how the couch gras is affected by season and competition from the wheat. Winter wheat is sown in September and harvested in august the year after
a) The mother rhizome start to develop roots that goes horizontally and finds nutrients to survive the winter. The rhizome has to be deep enough to be protected from the frost otherwise it will dry out.
When spring arrives the rhizome will start growing again and looking for nutrient, the shoot from the mother is developing while the daughter roots are developing however the shoots of the daughter will not show until late summer. This is however if there is no competition for nutrients. If there is competition there is also a risk for competition of sunlight and nutrients.
Questiop D2 (R. Glinwood— insects, IWts and diseases) (skipp d1)
You are an Integrated pest Management advisor. A new insect pest, a beetle. has anived in
your region and is now causing big problems in maiR, where it causes yield losses by
eating the leaves.
It is your job to design a strategy to nümage the pest. Because of EU legislation and demand
for organic produce from buyers. farmers are under pressure to reduce or avoid using
insecticides.
Research has provided the following information about the beetle;
- It was introduced from Asia and has no natural enemies in your region.
• A male produeed aggregation pheromone has becn dise•wered that attracts males and
females.
- Some cereals/grasses are very attractive to the plant hopper but others are knoun to be
- The beetle survives very poorly on several wild relatives Of maize.
Suggest different strategies the fanner could use for sustainable/integrated control ofthis
inscct (2 points). For each strategy give a brief description of how and Why it would
work (2 points).
1) Put up traps with the pheromones to attract the beetle away from the field, this traps the beetle inside. The trap has to be changed regularly to keep attracting the beetle. This works in a simple way just like a flytrap however there is a more complex way to do it that might give a better result.
2) I would do research on the natural enemy of the beetle, if it could be imported without damaging the natural fauna in any way. And lets say that its safe, I would then plant the wild maize in between the rows of the crop, this way the beetle might ley its eggs on the maize instead of the crop to minimize the survival rate. And lastly I would sow the attractive cereal on the edge of the fields to attract the beetle and plant the natural enemy in there ( a push pull system)
D3
Discuss possible ways to design and manage the cropping system to supress the development of fungal plant sjukdom
When designing a system you have to think of what fungi can survive in different crops, if there is a low survival chance (for the fungi) between two crops they should come after one another (we are not thinking of other pests in this scenario).
E2
Give an example of a biomass crop that currently is or potentially coud be grown on agriculturalland for energy piurpose, välj ställe själv. Discuss the advantages and disadvantages in terms of:
a) Agronomi
b) Biomass processing
c) Ecological/ environmental attributes of this particular ctop when grown for energy purpose under the conditions in the geographical region of your choice
a) Can be planted on “bad” soil, can use my existing machinery
b)
c) High output with low input, Makes my neighbours happy.
Question El (N.E. Nordh — energy crops) 3 points
In comparison to cultivation ofconventional agrieultural crops (i.e. cereals) the cultivation of
Salix (willow) differs in several aspects. For a farmer, used to grow conventional agricultural
crops, these differences might aliect the farmer’s decision on whether to start growing Salix
ornot. Give some examples (3) oft he differences between salix and conventional agncultural
crops and discuss them brieny from the farmer’s point ofview. (3p)
1) Long term commitment- planting salix binds you to that crop for several years before you can make a profit while a common crop is usually a one year commitment.
2) Different machinery- the farmer cant use the same machinery as for the other crops, the farmer has to either rent or by machines for each sowing/harvest
3) No security- the farmer gets paid to plant salix but not grow it, and because there is such a long commitment there is no guarantee that there will be a profitable market the year of harvest.
F1
You are studying winter wheat in an experimental site far away. You where out in the field in
the early Summer: you measured the CO2 assimilation rate and sampled the crop biomass
collecting. drying and weighting leaves and stems
a) How would you plan the timing of your next trip to the experimental site to sample the biomass at flowering? What information would you need? How coud you use it
If you were to discover that flowering has already happend, could you estimate
The crop biomass at stage? If so, how? (1 point)
a) I would use historical data of when the crop typically flowers and use the weather pattern both historical and the data that exist from sowing and forward to try to calculate the closest possible date of flowering.
b) Yes but only an estimation by using historical data and the data collected on my previous visit.
Look at the biomass I have and to a linear calculation of the estimated amount.
F2
Upscaling from the leaf to the whole plant
a) beskriv the big leaf model and the full anopy model, highlithing the main assumptions
b) which among the process included in the full cabopy model are overlocked by the big leaf modell?
a) Big leaf is when you assume that all the leafs are under the same conations all the time, either in the sun or in the shadow. The full canopy acconts for redistribution of light inside the canopy
b) growing canopy enhances photosynthesizing biomass, but potentially reduces available radiation and this is not covered by the big leaf.
Question 1 (F. Beyer – crop physiology) 5 points
Nutrient-use efficient crops will play an important role in the future because of limited
nutrient resources. You are supposed to carry out an experiment to evaluate a crop with high
nutrient-use efficiency (NUE).
a) Give a brief definition of NUE (1 p)
b) Describe the crop species of your choice you would like to investigate and discuss
why you believe that this crop is of particular interest for evaluating NUE. (2 p)
c) How would you analyse the NUE (2 p)
a) NUE is the plants ability to take up and convert nutrients (especially N) from the ground and use
it in an efficient way with as litte waist of energy as possible. With this produce a good yield.
Mass balances between final yield, plant N pool and soil N content
(NUE is defined as grain production per unit of N available in the soil, When the definition is
re- stricted to the ability of the plant to utilize applied N fertilizer it omits
variation in N mineralised during crop growth and hence is more related to agronomic efficiency.)
b) Perennial: Lepidium campestre, is a wild type plant that is in the process of being domesticated due
to its oil producing capacity. it works with rhizome bundles for nutrient uptake and also is good at recycling
nutrients. ______________________________New wheat?????
c) There is no right or wrong way, it depends on what you want to know. you could test the whole plant with soil,
the whole plant and soil separately och just the plant whole or split up. either way you want to test how the plant
absorbs the nutrients added, you could use a SPUD gun to measure the chlorophyll in the leafs, measure biomass
before and after fertilization ( a ”naked” control would be needed), look at root development, look att yield differences between treatments.
Question 2 (F. Beyer – crop physiology) 3 points
a) What are the three different types of competition within plants? (1.5p)
b) Name three (3) most limiting environmental factors for crop production especially at
northern latitudes? (1.5 p)
a) water availability, nutrient amount, // light (beror på hur hög växten är), space (to grow on)
b) Short growing period, freezing spells during late spring and early autumn, freezing during winter
(without the protection of snow), _________________________
Wild plants are more and more frequently used as genetic resources in plant breeding. For
example, wild relatives of maize adapted to high elevations have been used for the
improvement of cold tolerance in maize.
a) Explain why wild plants are important resources in breeding programs. In other
words, why do breeders not only focus on already domesticated cultivars for
improvement of crops?
(3p)
b) Are there any additional challenges breeders are facing when introducing wild
undomesticated plants into traditional breeding programs compared to making
crosses only between domesticated plants? If so, describe these challenges.
(2p)
a) the crops we have today has been domesticated during a long period of time
and during selective breeding we have lost alot of the natural diversity that still
exist in wild types today, this diversity helps the wild type to adapt to new environmental
challenges and pests. By incorporating some of the wild types natural diversity we can
improve on our existing crops and better prepare for the future to come.
b) yes, we don’t always know how the result will look like which could cause problems in
the field (new sowing/harvest times, new pests, new diseases m.fl.) we might not have the
tools to handle these problems either but thats why the breeding programs develop crops
during a long period of time. the second problem is that for example: a breeding program
i Canada that has developed a crop that works better in colder climates however that doesent
meant that it will work in countries with colder climates due to the fact that the temperature
doesent stand alone in a heap of factors that makes the crop successful.
