Agriculture and Food Supply

• what year was the Great Famine?

  1315 - 1317
• when was the Irish potato famine?

  the 1840s
• when was the little ice age?

  1303 - 1850
• what are the three main ways we have been able to sustain food production?

  plant breeding, genetic modification and agronomy
• what are the three main components of climate change which pose a threat to for production?

  increased atmospheric carbon dioxide concentrations, increased global temperatures and changing rainfall patterns
• what does crossing genetically related wild relatives with current crops produce?

  F1 hybrids with intermediate traits
• in short, how does the genetic modification of plants work?

  1. new DNA is transferred into the plant cells
  2. the cells are then grown in tissue cultures where they develop into plants
  3. the seeds produced by these plants will inherit the new DNA
• what are the advantages of plant breeding?

  it works and is free, limited technology is required and it is socially acceptable
• what are the disadvantages of plant breeding?

  it is time consuming and labour intensive and it is difficult to modify multi-genic traits
• what is agronomy?

  soil and crop management
• name three examples of soil and crop management?

  spray programmes, water management and fertiliser additions
• what is the yield gap?

  the difference between breeders trials and on-farm yield
• what does agronomy aim to do?

  boost crop yields towards their genetic potential
• how do we calculate the yield potential?

  light intercepted x radiation use efficiency x harvest index
• what are the key limitations preventing developing countries from reaching yield potential?

  lack of water and nutrients
• approximately what % of global emissions are agriculture responsible for?

  25 %
• what are two of the ways in which the agricultural industry contributes to global emissions?

  manufacturing of crop inputs like fertilisers requires energy and methane emissions from livestock and rice production
• what are the direct global emissions in agriculture?

  by industry practices
• what are the indirect global emissions in agriculture?

  beyond farm-gate
• what percentage of greenhouse gas emissions from agriculture is from livestock?

  more than 50 %