Ecology
Ranging from tropical very dry to moist through subtropical thorn to wet forest life zones, Jatropha is reported to tolerate annual precipitation of 4.8 to 23.8 dm (mean of 60 cases = 14.3) and annual temperature of 18.0 to 28.5°C (mean of 45 cases = 25.2).
It originates from tropical America, but has become naturalized in many countries and is common near habitations. It is well adapted to arid and semi-arid conditions.
Habitat
Latitude: 28oN to 30oS.
Altitude: Provenances have been collected from altitudes varying from 7 to 1600 masl. Usually it is found from 0 to 500.
Temperature: Average temperatures of provenance collection sites range from 11 to 28oC. It can survive a short, slight frost.
Water: Average annual precipitation of provenance collection sites is from 520 to 2000 mm. However the species survives well in semi-arid regions.
Radiation: Range & intensity: Bright sunlight. Photoperiodism: It is daylight insensitive.
Soil: Physical - It grows on well drained soils with good aeration and adapts well to marginal soils with low nutrient content. In heavy soils, root-formation may be reduced.
Distribution
It is native of the Caribbean region, has been introduced as a hedge & ornamental plant to many countries including Europe, Africa, India, Indonesia, Philippines & some Pacific Islands & Australia.
Cultivation
Grows readily, from cuttings or seeds.
Pollination
Jatropha is allogamous. Pollination is by insects. The plant is monoecious and flowers are usually unisexual.
Ecological Requirements
Jatropha grows almost anywhere, even on gravelly, sandy and saline soils. It can thrive on the poorest stony soil. It can grow even in the crevices of rocks. It is found in the tropics and subtropics and likes heat, although it does well even in lower temperatures and can withstand a light frost.
Its water requirement is extremely low and it can stand long periods of drought by shedding most of its leaves to reduce transpiration loss. Jatropha is also suitable for preventing soil erosion and shifting of sand dunes.
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