Other Flashcards
Nectar decrease fact
Nectar production decreased by 30% between 1930 and 1978
Bauds et al., 2016
What is most popular insecticide?
Neonicotinoids
Neurotoxins to most arthropods
What % of crop species need pollinators?
75%
What % of flowering plant species need animal pollination
88%
Value of pollinators
Breeze et al. 2015
£379-£695 million
Results of coating seeds in neonicotinoids
Negative results on honeybees - 24% population decline
Wind wild bees (Bombus terrestris) reproduction was negatively correlated with neonicotinoid residues
Woodcock et al., 2017
Neonics and honey
1/5 neonics found in 75% of worldwide honey samples
2/5 found in 45% of samples
% of UK’s land used for agriculture
70%
Pest control method
Beetle banks
Boost predatory insect numbers so control pests
Protect banks from spray
Also overwintering and protection from ploughing
Colorado beetle
Leptinotarsa decemlineata
Serious pest in USA
4 sp. predatory bugs/beetles attack it on potato leaves
3 sp. nematodes and bacteria attack it in the soil
On organic farms there was better ‘evenness’ of species abundances
Greater evenness meant more beetles were killed and potato plants benefitted
Crowder et al. 2010
Parasitoids quote
Parasitoids are one of the largest and most important group of pest controllers
Cross et al. 1999
Bumblebees and habitat quality
Carvell et al. 2017
Habitat quality significantly positively correlated with the survival of family lineages
Who does pollinator loss disproportionately affect?
Developing countries
What is ecological intensification?
Enhancing ecosystem functions that regulate and support production to get sustainable increases in crop yields
How much arable land does Earth have?
3.1/14.7 billion hectares
Number of species in Poaceae
857 genera
10,500-11,000 species
What is a grass?
- Monocot - parallel-veined leaves and flower parts in multiples of 3
- Perennial or annual herbs, stems erect, ascending, prostrate or creeping, round, hollow or solid at internodes, solid at nodes
- Leaves - alternate, composed of an open sheath, ligule and blade. Sheath encloses at stem
- Flowers - spikelets contain 1 or more florets; usually subtended by glumes
- Wide geographic range
Why most grasses can tolerate grazing
-Apical meristems are either underground or at ground level
What is the most efficient source of carbohydrate?
Rice
When did agriculture begin?
8,000-12,000 years ago
Where was wheat domesticated?
Near East
Where was corn domesticated?
Central and South America
Where was rice domesticated?
India and China
Biological and technological advances
- Introduction of new crops
- Mechanisation
- New and improved varieties
- Inorganic fertilisers
- Pesticides and fungicides
Further crop improvement
- High crop yield
- High nutritional quality
- Nitrogen fixation: less use of fertilisers
- Drought resistance
- Resistance to pests
- Insensitivity to photoperiod: multiple cropping during a growing season if they don’t respond to say length
- Plant architecture: positioning of leaves, branching pattern of stem, height of plant, positioning of organs
- Toxic or unwanted compounds
