Today’s the same plant. Flowers are unisexual or

Today’s
rising demand for fuels has diverted the attention towards biofuels due to
gradual exhaustion of fossil fuels and increased pollution, causing global
warming. Thus, an alternate source of energy is needed which is sustainable and
eco-friendly. Biofuel such as bioethanol and biodiesel has already been used in addition to the fossil
fueland have advantage in terms of renewability and environment friendly.
Biodiesel form plants and algae are being considered as most promising sources
of biofuels. 1. Biodiesel
from plants, is an excellent substitute for fossil fuels as it is non-toxic,
biodegradable and emits lower amount of carbon monoxides and hydrocarbons than
petro-diesel. An important component of plant seed oils is triacylglycerols which
are highly similar to fossil fuels thus, an excellent precursor for producing
biodiesel. Transesterification of triacylglycerols in plant seed oils
with methanol in presence of an alkali or acid resulting in formation of
biodiesel chemically known as fatty acid methyl esters (FAMEs)2. The efficiency of biodiesel
depends upon the composition of fatty acids blend in the seed oil. Five types
of fatty acids are present in plant oils which are Palmitic acid (16:0),
stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2) and linolenic acid
(18:3). Earlier, edible crop plants were used for biodiesel production which
caused the scarcity for overall food supply and agricultural lands. Thus, for
sustainable biodiesel production, non-edible crops have gained importance due
to non-competition with food security and soil with food crops. Ideal biodiesel
crop can be grown in wastelands thus no competition for agricultural land for food
crops 3.  

 

Of
many energy plants, Jatropha (Jatropha
curcas L) has emerged as a potential bioenergy plant due to its high seed
oil content (45-50%). Jatropha is a perennial shrub or a small tree which
belongs to family euphorbiaceae. It can grow upto a height 6 m and have 40-60 years of life
expectancy. Oil can be extracted from Jatropha seeds after 2-5 years depending
upon the climatic conditions. Jatropha is a monoecious plant i.e. male
and female flowers grow on the same plant. Flowers are unisexual or
hermaphrodite and are pollinated by moths and bees (Raju and Ezradanam, 2002;
Dehgan and Schutzman, 1994). Morphologically
diverse genus Jatropha comprised of more than 200 species which are dispersed primarily
in dry tropical areas of America. Jatropha, primarily originating from Central
America, has been recently introduced into many tropical and subtropical
countries in Asia and Africa. Now Jatropha is cultivated globally as a
biodiesel crop (Akbar et al.  2009). It
is introduced in India in 16th century by Portuguese settlers. About
18 species of Jatropha are found in India and are scattered in various states
of the  country (Ginwal et al 2005).   Jatropha can easily grow in extreme
conditions such as in tropical savannah and monsoon climates, temperate and
semi-arid climates without any requirement of special nutritive regime (Maes et
al. 2009). Other factor for Jatropha oil popularity is the higher content of
unsaturated fatty acids and high oil content (50%) and a non-edible crop, thus
no competition with food security (Table 1.1). Jatropha is listed as a fuel and
fuel additive with the world environmental protection agency (WEPA) 7. Jatropha
gained prominence over other oil seed plants because of its added features like
excellent adaptability to various habitats, rapid growth, easy propagation,
wide adaptability, larger fruits and seeds, drought hardiness, soil
conservation capabilities, small gestation period, thriving well as live fence
and can easily be grown in wastelands. Jatropha seeds are toxic due to the presence of phorbol
esters and curcin. Even though it’s a potent biodiesel crop and toxic in
nature, it has a medicinal value. Most of the parts of Jatropha is used as
industrial raw material for making insecticides, soaps, cosmetics etc and a
source of green manure (Gubitz et al., 1998; Lin et al., 2003). Though numerous efforts have
been made to develop J. curcas as an
industrial crop, the scant information on its agronomic practices and lack of
improved genotypes and cultivars are the major bottlenecks in its full
exploitation as a potential bioenergy crop