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GM Adoption

Widespread use of genetically modified crops.

Stacked Genes

Combination of traits like insect resistance and herbicide tolerance.

Genetic Engineering

Manipulation of an organism's genes using biotechnology.

Gene Construct

Artificially created DNA sequence for gene transfer.

Promoter Gene

Regulatory sequence driving gene expression.

Trait of Interest

Specific characteristic targeted for modification.

Marker Gene

Gene used to identify successful gene transfer.

Restriction Endonucleases

Enzymes that cut DNA at specific sequences.

Bacterial Plasmid

Circular DNA used to transfer genes into bacteria.

Agrobacterium-Mediated Transfer

Gene transfer method using plant pathogen Agrobacterium.

Biolistic Bombardment

Gene gun method for delivering DNA into cells.

In Vitro Selection

Choosing transformed cells using selectable markers.

Plant Tissue Culture

Technique to regenerate plants from transformed cells.

Genome Editing

Precise modification of an organism's DNA.

Non-Targeted Insertion

Random integration of foreign DNA into the genome.

Targeted DNA Insertion

Specific placement of DNA into the genome.

Marker-Free Insertion

Gene transfer without selectable marker genes.

Effectiveness of GM Crops

Quantifiable benefits like yield increase and damage reduction.

Human Health Issues

Concerns regarding allergenicity and herbicide residues.

Transgene Escape

Unintentional transfer of genes to wild relatives.

Drought-Tolerant GM Rice

Research area with no commercial releases yet.

Heat-Tolerant GM Wheat

Approved second generation GM crop for high temperatures.

steps in genetic engineering

create gene construct in vitro, use restriction endonucleases to insert genes into bacterial plasmid, transfer plasmid, in vitro selection of transformed cells growing on selectable marker, recovery of transformed cells using plant tissue culture

advantages of GM crops

introduce new traits, selectively modify single genes regulating traits, precise location of new genes, faster, increase yield, profit and convenience

disadvantages of GM crops

possible human health issues, effects on nontarget organisms. transgene escapes

herbicide residues in GM crops

glyphosate and AMPA accumulate in GM soybean - residue levels have some effect on mammalian liver/kidneys - uncertain biological significance

effects of GM crops on non target organisms

herbicide resistant weeds, monarch butterflies - caterpillars eat toxic GM pollen which falls on milkweed

Environmental changes effect

Threats to food production sustainability.

Socioeconomic factors effect

Influence food production, e.g., historical famines.

Overpopulation def

Demand for food exceeds production capacity.

Plant breeding

Technique to enhance crop yield and resilience.

Genetic modification

Altering organisms' DNA for desired traits.

Agronomy

Science of soil management and crop production.

Soil salinity

High salt concentration affecting crop growth.

Soil erosion

Loss of topsoil reducing agricultural productivity.

Desertification

Land degradation leading to desert-like conditions.

Climate change

Long-term alteration of temperature and weather patterns.

Atmospheric CO2 concentration

Current level around 405 ppm affecting growth.

Global temperatures

Rising temperatures impacting agricultural yields.

Changing rainfall patterns

Altered precipitation affecting crop viability.

Temperature effects on yield

Higher temperatures speed up plant life cycles.

Predictive yield modeling

Forecasting future crop yields using simulations.

Backcrossing

Crossing hybrid with parent to recover traits.

Flood tolerant rice

Rice varieties adapted to withstand flooding.

Drought tolerant rice

Varieties developed for better drought resistance.

High temperature tolerance

Increased resilience of crops to heat stress.

Harvest index

Ratio of grain yield to shoot biomass.

Potato blight

Fungal disease exacerbated by climate change.

Coevolution

Host-pathogen interaction driving resistance development.

how have we sustained food production

plant breeding, genetic modification, agronomy

current threats to food production

soil salinity, desertification & erosion, lack of incentive for rural careers. climate change

3 main components of climate change

increased atmospheric co2, increased global temps, changing rainfall patterns

3 sets of variables in trials implementing climate change treatments

co2 concentration (370 ppm vs 740), temp (20/18 vs 28/24), water levels - well watered vs drought

findings of climate change treatment trials

temp/drought effects were greater under elevated co2

What has been the trend in crop yields according to historical analysis?

Crop yields have increased.

What effect does rainfall have on crop yields according to historical analysis?

Rainfall had no effect.

How does temperature affect crop yields?

Yield decreases when temperature increases.

Why do yields decrease when temperature increases?

Plant life cycle speeds up, resulting in less time for development.

steps in plant breeding

select wild relatives showing gene of interest, cross parental lines. stress-tolerant plant crossed with existing elite cultivar, select offspring that show both traits, multiple generations of backcrossing

advantages of plant breeding

works, free, limited tech needed, socially acceptable

disadvantages of plant breeding

time consuming, labour intensive, difficult to modify multigenic traits, rate of genetic gain can't keep up with climate change and population growth

how to increase drought tolerance

introduce genes from wild relatives that show greater root growth

ways of experimentally imposing high temps

late planting , use plastic screens to augment natural temp variation, simulate climate change in growth chambers

what is the problem with blight resistant potatoes

not favoured by customers

Agronomy

Science of soil and crop management practices.

Yield Gap

Difference between potential and actual crop yields.

Crop Rotation

Alternating different crops in the same area.

Intercropping

Growing two or more crops in proximity.

Break Crop

Crop grown to interrupt pest cycles.

Nutrient Management

Balancing soil nutrients for optimal crop growth.

Soil pH Management

Adjusting soil acidity for nutrient availability.

Irrigation

Artificial application of water to crops.

Microbial Inoculants

Microorganisms added to enhance plant growth.

Crop Protection

Methods to control pests and diseases.

Yield Potential Formula

Light intercepted x radiation use efficiency x harvest index.

Global Emissions from Agriculture

Agriculture contributes 25% of global greenhouse gases.

Methane Emissions

Primarily from livestock and rice production.

1-MCP

Ethylene antagonist to prevent heat-induced grain loss.

Alternate Wetting and Drying (AWD)

Irrigation method reducing water use in rice.

Fertiliser Impact

Main source of greenhouse gas emissions in agriculture.

Soil CO2 Release

Carbon dioxide emitted during seedbed preparation.

Livestock Emissions

Over 50% of agricultural greenhouse gas emissions.

Heat Stress Resistance

Ability of crops to withstand high temperatures.

Chemical Arms Race

Competition between blight, farmers, and regulations.

Fungicide Effectiveness

Varies over time; fewer new compounds developed.

Water Table Measurement

Technique to implement AWD in rice farming.

Crop Management Practices

Influence greenhouse gas emissions from agriculture.

why are crop yields stagnating in europe

crops may have reached their genetic yield potential, plant breeding may not be sufficiently funded, soil compaction could be limiting wheat yields

australia - yield changes

yields are limited by rainfall & boosted by agronomic innovations, yield potential decreasing due to rising temps and decreased rainfall

sources of co2 from agriculture

lost carbon sequestration, manufacture of crop inputs eg. fertiliser, soil co2 released during seedbed prep, methane emission from livestock

effects of AWD in rice

increased yield, decreased water use, decreased global warming potential

ethylene use

delay fruit ripening or flower senescence

mechanism of plant hormone action

endogenous/environmental factors, ethylene production, ethylene binds to receptors in plant tissue, physiological response

nontoxic potato blight compound

potassium phosphite - degrades into K and P in the plant, similar effectiveness to some fungicides, tubers contained less starch

pollutant

a chemical that is in the wrong place at the wrong concentration, that has the potential to cause damage to the environment

air pollutants

chemicals that are emitted into the atmosphere which adversely affect physical and biological systems

primary pollutants

chemicals that are emitted directly into the atmosphere

primary pollutant eg.s

NO, SO2

secondary pollutants

chemicals that are formed by the reactions in the atmosphere between primary pollutants and other agents

secondary pollutant egs.

NO2, ozone O3