Title :
Plant Nutrition
Author :
Kim Foglia & Kelly ReidellNumber of slides:
27
Source:
Slideshow :
Content transcript :
Physiological adaptation
Nutritional needs
* Autotrophic does not
mean autonomous
* plants need…
* sun as an energy source
* inorganic compounds
as raw materials
* water (H2O)
* CO2
* minerals
Macronutrients
* Plants require these nutrients in relatively large amounts
* C, O, H, N, P, K, Ca, Mg, S
For what & from where?
Local Long Island soil issues
Micronutrients
* Plants require in very small amounts
* Cl, Fe, Mn, Bo, Zi, Ni, Mb
* primarily cofactors for enzyme function
Nutrient deficiencies
* Lack of essential nutrients
* exhibit specific symptoms
* dependent on
function of nutrient
* dependent on
solubility of nutrient
Magnesium deficiency
* Symptoms
* chlorosis = yellowing of leaves
* Why? What is magnesium’s function?
Chlorophyll
The role of soils
* Plants are dependent on soil quality
* texture / structure
* relative amounts of various sizes of soil particles
* composition
* organic & inorganic chemical components
* fertility
Importance of organic matter
* Topsoil
* most important to plant growth
* rich in organic matter
* humus
* decomposing organic material
* breakdown of dead organisms, feces, fallen leaves & other organic refuse by bacteria & fungi
* improves soil texture
* reservoir of minerals
* organisms
* 1 tsp. of topsoil has ~5 billion bacteria
living with fungi, algae, protists, insects,
earthworms, nematodes
Soil health as a global issue
Not taking care of soil health has
far-reaching, damaging
consequences
* 1920’s Dust Bowl
* lack of soil conservation
* growing the same crop
year after year (wheat)
* grazing by cattle
* bare ground exposed to
wind erosion in winter
* drought
Soil health as a global issue
* Soil conservation & sustainable agriculture
* maintaining healthy environment
* sustainable production of food supply
* economically viable farming industry
Global Issues
* soil fertility
* erosion
* irrigation
* forestry destruction
Fertilizers
* “Organic” fertilizers
* manure, compost, fishmeal
* “Chemical” fertilizers
* commercially manufactured
* N-P-K (ex. 15-10-5)
* 15% nitrogen
* 10% phosphorus
* 5% potassium
Nitrogen uptake
* Nitrates
* plants can only take up nitrate (NO3-)
* Nitrogen cycle by bacteria
* trace path of nitrogen fixation!
Soybean root nodules
* N fixation by Rhizobium bacteria
* symbiotic relationship with bean family (legumes)
Increasing soil fertility
* Cover crops
* growing a field of plants just to
plow them under
* usually a legume crop
* taking care of soil’s health
* puts nitrogen back in soil
Some plant oddities…
Parasitic plants
* tap into host plant vascular system
Plants of peat bogs
* High acid environment
* most minerals & nutrients bound up & are not available to plants
* must find alternative sources of nutrients
Carnivorous
plants
Are they really carnivores?
Uses of peat
Any Questions??
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