Anther culture for the production of haploid and doubled haploids in Jatropha curcas L. and its hybrids

Jatropha curcas L. has recently received considerable attention for the production of sustainable and affordable biofuels. Large scale cultivation of Jatropha requires homozygous parental genotypes to develop sustainable high yielding hybrids. Doubled haploid culture has been shown to offer the shortest method of producing homozygous plants and to permit greater selection efficiency since all the genes are fixed in a homozygous stage. In the present study, an efficient in vitro method for plant regeneration via anther culture of Jatropha was developed. Efforts were taken to induce callus from anthers of immature buds of seven elite genotypes and hybrids of Jatropha. Highest percent callus (77%) induction was achieved from anthers cultured on MS medium supplemented with BA (1.0 mg/l) and Picloram (1.0 mg/l), but callus obtained on media with BA (1.0 mg/l) and 2,4-D (1.0 mg/l), Kinetin (0.5 mg/l) and 2,4-D (2.0 mg/l), and BA (0.5 mg/l) and NAA (2.0 mg/l) showed regeneration of plants on medium containing BA (2.0 mg/l), Kinetin (0.5 mg/l) and NAA (0.5 mg/l). Rooting was achieved in 90% of the elongated shoots on half-strength MS medium with IBA (2.0 mg/l). All in vitro anther-derived plants were transferred to a greenhouse with 100% success in primary hardening and around 85% in secondary hardening. Plants established in the field are growing well as normal plants. Molecular and flow cytometry analyses of embryogenic callus revealed 5.7% and 3% samples are haploid and doubled haploid, respectively.