wee 1 Flashcards
(36 cards)
What is the concept of food security?
The objective of the first lecture is to explain the concept of food security. It is presented as being more complex than simply having enough calories or just having enough food. It includes a qualitative aspect
What is the importance of food security?
Food security is highlighted as a crucial challenge for tomorrow that civilisations need plant science to face. Its importance is underscored by the increase in the world population.
-Plants are fundamental, described as supporting all other life (“Man and all other animals are in reality guests of plants on this earth”).
-Everything we eat comes directly or indirectly from plants, and plants provide essential resources for everyday life, from food and drinks to building materials, clothes, and paper.
-Crops have made civilisations possible.
What does the IPCC report on food security?
the idea that increased population puts pressure on food production, which is linked with plants, was repeated in the IPCC report in 2019. Chapter 5 of the 2019 IPCC report specifically focuses on Food Security
What is the food security definition from the 1996 World Food Conference?
The definition of food security from the 1996 World Food Conference states that “Food security exists when all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life”. This definition is described as sounding “like paradise”.
What are the four main components of food security? How can plant sciences address some of them?
The main components of food security outlined in the 1996 definition are:
-Availability: Having enough food.
-Access: Everyone being able to access or buy food.
-Affordability: Food being able to be bought at a fair price.
-Quality: Food meeting required nutrient needs for a healthy diet and being safe
Plant science is argued to be able to address the issues of quality, affordability, and availability, particularly by contributing to production and yield which contribute to availability. It’s noted that availability is not solely a plant science problem, as political aspects are also involved
Why is food security is a challenge?
-core challenge is to produce and supply enough safe and nutritious food in a sustainable way for a growing global population.
-global population reached 8 billion in 2022 and is projected to reach 9.7 billion by 2050, potentially exceeding 10 billion after 2050 or 2060.
State what is meant by arable land? How is global arable land per capita changing?
Arable land is defined as the land on which crops are grown.
-Global arable land per capita is diminishing because the amount of arable land is finite (around 30-32% of the planet’s surface) while the world population is increasing.
-Projections indicate significantly less arable land per person in 2050 compared to 1950 (e.g., 250 square meters projected for 2050 vs. 5,000 in 1950).
-A key challenge is to produce the necessary food without destroying biodiversity.
Why has food security become an increasing challenge in recent years?
-Food security has become an increasing challenge, described as a “perfect storm” where multiple problems converge:
-Increasing population: As mentioned, the global population is growing rapidly.
-Changing diets: As people become more affluent, they tend to eat more meat, which requires more energy (and thus more arable land) to produce compared to plant-based diets.
-Reduced arable land: Arable land available for food production is competing with the production of agro-fuels (crops grown for biodiesel, etc.).
-Climate change: Increasing temperatures and drying out linked to climate change are reducing crop yields
What challenges have risen from trying to feed a global growing/more affluent population?
-Feeding a growing and more affluent global population requires significant increases in food production.
-Estimates suggest cereal production needs to increase by 50% and meat production by 85% between 2020 and 2050 to meet demand.
-The primary challenge is achieving these production increases without “wrecking the planet”.
Can food security be achieved without harming the planet? How?
The challenge is to balance increased production with environmental impact.
-this can be worked towards through sustainable intensification of agriculture.
-the idea is to increase yield to limit damage to biodiversity and ecosystems.
-higher yield farming can potentially help “spare nature” by freeing up land for conservation.
How has climate change (particularly increasing CO2 emissions) influenced crops?
Rising atmospheric CO2: Can potentially be an advantage for photosynthesis and higher yield, especially at high latitudes. Atmospheric CO2 levels were around 426 ppm as of January 2025.
Temperature increase: Increases in growing season temperatures are linked to decreased agricultural yield at current latitudes.
Drying out: Drought has a negative impact everywhere and there are gaps in understanding drought physiology.
While CO2 itself is useful to plants, the side effects of climate change mean the overall effect is generally detrimental to crop production
How can plants modified to adapt to climate change?
Crops’ regulatory genetic networks will need to be modified to speed up adaptation to climate change. Research is needed to find better genes for plants to resist climate change and keep producing enough food.
What is the green revolution?
The Green Revolution refers to a set of newly implemented technologies, including new breeds of high yield crops (like dwarf crops), as well as pesticides and synthetic fertilizers, that resulted in doubling global food production in 20 years, starting around the 1960s.
It had a massive effect on yield for crops like wheat.
While it had some negative political/societal consequences, its impact on yield is seen as something to hope to reproduce
Why should we be worried about recent trends in plant science?
Recent trends in yield increases are worrying because they are “going the wrong way”.
-Yield increases for major crops like wheat and rice have flattened or significantly slowed down compared to previous decades. -For example, wheat yield gain was minimal up to 2007 and has further decreased since.
-This plateauing effect means we are not currently on track to double yield again by 2050, indicating the need for a “step change”. -Furthermore, it takes time for new genetic material and technologies to permeate agriculture worldwide, as illustrated by the nearly 20-year gap in adopting Green Revolution wheat genetics in India/Pakistan after their development in Mexico
Why increase yield?
Yield needs to be increased for several key reasons:
-To feed an increasing population.
-To accommodate changes in diet towards more meat consumption.
-To compensate for reduced cultivated land per capita.
-To limit the expansion of cultivated land to preserve habitats and reduce CO2 emissions.
-To compensate for yield loss due to climate change.
What are suggested solutions from a plant science point of view?
Research and Discovery: Finding better genes to help plants resist climate change and produce more food.
Speed Breeding: Accelerating traditional breeding processes (which can take 20 years) to just a few years.
Using GM Technology: Using GM technology, even if not for the final solution, to speed up the discovery process for potential non-GM applications later.
Rapid Knowledge Transfer: Transferring knowledge quickly from model species to crops.
How will the N8 Universities help tackle the global food security issue?
The University of Manchester is part of the N8 Agri-Food Resilience Programme, where universities in the North of England collaborate to tackle global food security. This is done through three interconnected multidisciplinary research themes:
Sustainable Food Production (which includes plant science).
Resilient Food Supply Chains (more economic aspects).
Improved Nutrition and Consumer Behaviours (involving psychologists, etc.). This involves collaboration between plant scientists, economists, psychologists, and others
What is a nastic movement?
A nastic movement is one of the two broad types of plant movement mentioned.
These movements do not have a specific direction.
They do not respond to the direction of the stimulus.
Instead, they respond to a specific stimulus itself, such as touch or temperature.
Examples include thigmonasty and thermonasty
What is the example of nastic movement in sensitive plant (mimosa pudica)?
The sensitive plant, Mimosa pudica, is a well-known example of nastic movement visible in real time.
It reacts to stimuli like heat or touch.
When stimulated, its leaves fold.
The plant’s response is proportional to the intensity of the stimulus; a stronger stimulus leads to a stronger folding response.
What is the example of nastic movement in carnivorous plants?
Carnivorous plants, such as the Venus fly trap (Dionaea muscipula), also exhibit nastic movement.
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In the Venus fly trap, touching the trigger hairs inside the trap causes the trap to fold rapidly.
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This response is specific to touching the trigger hairs; messing with other parts of the trap does not cause it to fold.
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The Venus fly trap can count the number of touches to its trigger hairs to fine-tune its response. Two touches within a short time (15-20 seconds) trigger the trap to close. Subsequent touches lead to further responses, like the activation of digestive enzymes after the third signal and nutrient uptake after the fifth signal. This intricate response involves converting mechanical touch into electrical signals (action potentials), activating touch hormones (like jasmonate) from the second action potential, and triggering gene expression for enzymes needed for digestion
What is thermonasty?
Thermonasty is a type of nastic movement specifically caused by temperature.
This movement can be observed on a slower timescale.
Examples include daisies and some tulips, whose flowers open when it is warm and close when it gets cold, such as in the evening.
How do plants use internal circadian clock?
Plants possess an internal circadian clock.
This clock allows them to predict events linked with the day/night cycle.
One manifestation is the “sleep response” observed in some plants like beans, where leaves fold at night and open during the day. This rhythm persists even in continuous dim light, demonstrating it is controlled by the internal clock rather than being a direct response to light.
The circadian clock also influences other movements like circumnutation, where increased movement is observed at night.
Furthermore, the circadian clock is integrated with directional growth responses like phototropism. For example, sunflowers anticipate sunrise by turning their heads towards the east before the sun appears, maximising light capture.
Plants use the circadian clock for long-term integration and evaluation of environmental inputs like light or temperature. This information is recorded and recalled as a form of cellular memory, influencing their future behaviour, such as determining the appropriate time to flower
What is circumnutation?
Circumnutation is described as a helical organ movement that is widespread among plants.
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It was studied by Darwin.
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During circumnutation, the tips of organs like stems move in a circling pattern.
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This movement can be influenced by the circadian clock, with more agitated movement sometimes observed at night.
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In climbing plants, circumnutation helps the plant explore its surroundings to find support.
What is a tropism? State the 3 types?
A tropism is a directed response to a directional stimulus. The plant senses the stimulus in a specific direction and grows or moves in a corresponding direction
Tropisms:
1. Gravitropism: Response to gravity.
2. Thigmotropism: Response to touch.
3. Phototropism: Growth towards or away from light.
4. Hydrotropism: Growth towards water.
5. Thermotropism: Growth towards or away from temperature.
6. Chemotropism: Growth towards nutrients
