Altitude and insolation are the most important determinants of suitable climate for tropical crop production.
False
The tropic and subtropic regions of the earth lie within ____ degrees of the equator.
30
In general, rainfall decreases as latitude increases and also falls with increasing elevation.
True
There are 12 temperature regimes in the tropics. List four.
Equatorial
Tropical
Tierra templada
Tierra fria
Andine
Semitropical
Marine
Temperate
Pampean-patagonia
Continental
Polar
Alpine
The major constraint to the realization of the potential productivity in these regions is attributable to _________________.
Poor quality soils
In a slash and burn cropping system, a __ year resting period is considered necessary to restore soil fertility after 3 years of farming.
8
When is planting done in a permanent upland cultivation system?
At the onset of the rainy season
Planting at the onset of the wet season is critical for cereal cropping systems in West Africa to receive the benefit of nitrogen produced in a burst by soil microbes.
True
Why are Cassava tubers not eaten raw?
They must be detoxified first due to the high concentrations of cyanide.
What is the most important food crop in the world?
Rice
Rice yields are greatest during the _______ season.
Dry
Define Oxisols
Oxisols: Highly weathered and leached, and lack distinct horizons.
Define Vertisols
Vertisols: Typically contain over 30% clay and known for poor physical structure.
Define Andisols
Andisols: Highly permeable, glassy, and generally the most productive upland soils.
Define Alluvial
Alluvial: Are the results of relatively recent sedimentary deposits and have little or no horizons.
Define this perennial crop: Avocado
Avocado: Produces a berry with a leathery skin and remains hard as long as it is on the tree.
Define this perennial crop: Banana
Banana: Fruit develops parthenocarpically as a bunch and are planted at a density of 8,100 plants per acre.
Define this perennial crop: Cacao
Cacao: Production areas are within 20 degrees of the equator and below 1,000ft altitudes.
Define this perennial crop: Citrus
Citrus: Production areas are within 30 degrees of the equator and disease problems are more devastating than insect pests.
Define this perennial crop: Coconut
Coconut: Tolerates high salt levels in soils and must be propagated by seed because no part of the tree can be used for vegetative propagation.
Define this perennial crop: Coffee
Coffee: Produces a drupe fruit from clusters of two to twenty perfect flowers that last only 3 days.