Phosphorus Crisis Flashcards
What are the 3 major pools of phosphorus?
- Labile P e.g. orthophosphate
- Complex inorganic P
- Organic P
How much labile P in soil?
0.1-1%
What countries have low levels of labile P and high Fe?
Brazil and Australia
How much mined rock phosphate is applied each year?
18 million tonnes / year
How much rock phosphate makes 1kg of P?
7Kg rock phosphate = 1Kg of P
What can be done to combat the phosphorus crisis?
Direct:
- Increase plant P use efficiency
- Reduce reliance on rock phosphate
- Improve recycling of organic P
Indirect:
- Improve crop resistance
- Improve P recovery
- Improve animal P use efficiency
What is the importance of microbes in agriculture?
- Plant growth promotion
- Plant pathogen suppression
- Nutrient acquisition
- Bioremediation
What are the niches in the plant microbiome?
Phyllosphere : above ground mass
Rootendosphere : roots
Rhizosphere : zone of chemical, biological, and physical influence around roots
What is rhizodeposition?
Process in which plants attract microbes.
Occurs in rhizosphere
How many microbes are there in soil?
10^10 - 11 cells per gram of soil
When was the rhizosphere termed?
1904
What is different about the early and late research of plant microbiomes?
Early: culture dependent
Late: culture independent
What does in situ analysis of gene and enzyme expression in the microbiome allow?
Links structure and function to biotic and abiotic conditions