Abstract
Jatropha curcas is a small bush who has attracted
the attention as an energy crop for the biodiesel
production. A number of reports have been
published regarding to the toxic J. curcas but
there is little information relating to non-toxic
J. curcas. A simple, high-frequency protocol
for plant regeneration through organogenesis
and somatic embryogenesis has been developed
in cultured explants of non-toxic Jatropha
curcas with different plant growth regulators.
When Thidiazuron was used at concentrations
of 3.5 and 4.5 μM, leaf explants showed the
best response, forming a highly organogenic
callus from which 78 and 64 shoots/explant
were obtained. However, when Benzyladenine
was combined with Indoleacteic acid, the
hypocotyl explants showed a greater capacity for
organogenesis compared with the leaf explant,
both in indirect organogenesis (112 ± 1.8 shoots/
explant) and in direct organogenesis (82 ±1.6
shoots/explant). Somatic embryogenesis was
induced directly from leaf explants which were
exposed to 8.9 μM of Benzyladenine + 5.6 μM
of 2,4-Dichlorophenoxyactic acid. After 12
weeks of culture, the embryos began to turn
green and eventually germinated. The shoots
were elongated (73%) in the presence of 2.8 μM
of Giberellic acid.
Keywords : Regeneration, biodiesel, plant growth
regulators, somatic embryos, adventitious
shoots, shoot elongation.
Introduction
The search of new sources for the alternative
energy production is one of the main objectives
of the international community. One subject that
has been receiving attention is the search of nonedible
crops that facilitate the biofuel production
in an efficient manner (Kumar et al 2010a, Kumar
et al 2010b). Among the existing biofuels we
found the biodiesel which can be obtained from
several sources such as rapeseed, sunflower,
soybean, oil palm, linseed, cotton seed and beef
tallow (Achten et al 2010). One of the candidate
crops is Jatropha curcas (J. curcas) which is a
multipurpose perennial shrub from the tropics
and subtropics of South America Achten et al
2010). J. curcas (Euphobiaceace) has attracted
the attention from various developmental
agencies due its medicinal properties, resistance
to various stresses and recently as an oilseed
crop for the biodiesel production given its high
oilseed content (40%) Martínez-Herrera et al
2010). One of the advantages of this species
is the fact that its seed is not consumed due
its toxicity and it can grow in low moisture
soils (Martínez-Herrera et al 2010). Mexico is
considered the center of origin of this species
and it is the only place were non-toxic cultivars
can be found, although they are not particularly
abundant (Sujatha et al 2005, Achten et al 2010,
Martínez-Herrera et al 2010). The byproducts
of non toxic cultivars can be used animal fodder
given its high protein content (Martínez-Herrera
et al 2010).