Energy security is defined as “the uninterrupted availability of energy sources at an affordable price”. Being non-renewable in nature, the fossil fuels are likely to become exhausted in future. Consequently, there has been always an interest in alternative and renewable sources of energy. Over past several years, biofuels have been proposed as a potential renewable alternative to fossil fuels. Jatropha curcas, a member of family Euphorbiaceae, in 2002 identified as the most suitable tree borne oil seed for biodiesel production by Government of India. Availability of high yielding varieties is a basic requirement in agricultural production. Marker-assisted breeding has become a common practice in genetic improvement of different crops. The objectives designed were chiefly aimed at generation of genetic information and prebreeding material in Jatropha that could be used in molecular breeding to improve the traits such as seed and oil yield, disease resistance and wood related traits. In this study, an advanced inter-specific mapping population was generated and established in the field by using the individuals of a previously developed BC1 population as parents. A high-throughput genotyping method, Genotyping-by-sequencing (GBS), using Next Generation Sequencing along with AFLP and SSR markers was used to genotype two independent populations of Jatropha. A highly dense linkage map was developed in Jatropha with an average marker to marker distance of 0.11 cM. A total of 3401 previously unmapped genomic scaffolds belonging to two reference genome assemblies (3267 Jat-r4.5 scaffolds and 134 Wu-JatCur-1.0 scaffolds) were mapped on different linkage groups of Jatropha. Different QTLs were also identified for JMD, wood and oil related traits, 100-seed weight etc. The prevalence of Apomixis in Jatropha was also studied using various AFLP and microsatellite markers. It was concluded that events of apomixis in Jatropha in populations derived from interspecific hybridization are extremely rare, although they may not be completely absent. Finally, there is an important need for reworking the economics of the entire Jatropha value chain based on realistic data. Furthermore, market reforms and procurement policies, such as contract farming, and public-private partnership need to be in place for economic sustainability of this value chain.
Key Words of the Research: Biodiesel, Jatropha, Linkage mapping, QTL mapping, Apomixis, Genotyping by sequencing
Shodhganga Link (Update by January 2023)