The Disadvantages of Jatropha
Jatrophas are popular tropical garden specimens due to their dark green foliage and robust pink-to-red blooms. There are many biodiesel energy proponents that are hoping jatropha will be the miracle biodiesel source for countries that want to reduce their diesel imports, according to the ECHO website. However, both as a garden specimen and as an alternative energy source, jatropha has quite a few limiting factors.
Uganda and other countries are exploring the use of Jatropha curcas nuts for biodiesel fuel production in order to lessen their dependence in imported oil. One disadvantage is that jatropha is toxic to livestock, which the multitudes of tenant farmers raise for their often meager sustenance. Most of the Jatropha plant is also toxic to humans, and so biodiesel pioneers are attempting to find a plant that is useful for food and livestock feed as well as biodiesel fuel. Jatropha also does not produce well on marginal farmland, and this is the majority of the farmland being offered for jatropha production. Without massive soil nutrient inputs, jatropha is not a cost-effective alternative to imported oil, according to the ECHO website.
For gardeners who want to enjoy the deep green foliage and red blooms of the ornamental jatropha plant, climate has to be taken into account. Jatropha is not hardy, but grows large. Growing jatropha indoors can be problematic due to the immense size of adult jatropha, especially because it keeps getting larger as it ages. Moving jatrophas indoors during inclement weather is possible, but the size and weight of the plant can be limiting factors.
Host for Disease
Root rot, leaf spot and fungal rust diseases have all been reported Jatropha plants. All cause plant damage, and root rot can be fatal to the plant. Cassava superlongation disease and the African cassava mosaic virus are both hosted by Jatrophas. In Africa and parts of South America, these diseases have devastated cassava food crops. In some areas, more than half of the cassava crop has been lost due to the African cassava mosaic virus.
Jatropha curcas has poisonous fruit and seeds. Ingestion can cause digestive irritation, including diarrhea and nausea. The University of Purdue warns that children may also experience depression and collapse. The poisoning may even cause death. According to the University of Florida Extension Service, all parts of Jatropha multifida are poisonous.