Studies on genetic diversity of Jatropha curcas L. Genotypes by RAPD and ISSR markers

Abstract

Jatropha curcas had gained popularity as a potential biodiesel producing crop but the major constraint for improvement of the crop for yield and seed quality traits (like seed oil content) is the narrow genetic base of the germplasm. In the present study, genetic backgrounds of 16 Jatropha curcas accessions from different locations of Punjab have been elucidated using molecular markers. For this work, total genomic DNA was isolated from Jatropha using a simple and efficient method. Quality and quantity of the genomic DNA preparations were checked by using agarose gel electrophoresis and nanodrop spectrophotometric analysis. Restriction analysis clearly reveals that the genomic DNA preparations are essentially devoid of inhibitory substances. Molecular analysis was carried out through PCR-based Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeat (ISSR) techniques. RAPD and ISSR are inexpensive and rapid methods, they do not require any information regarding the details of the plant genome and have been widely used to ascertain the genetic diversity in Jatropha curcas L. This is only a preliminary study with regard to genetic diversity analysis of a few select Jatropha germplasm. In this study, only a total of 5 RAPD and 5 ISSR markers were used to investigate polymorphism in 16 Jatropha curcas. Most of them refers to elite accessions in terms of seed yield and oil content. Banding patterns of the amplified DNA for a particular primer were found to be nearly identical for all the accessions, but the difference could be noticed with regard to the range of band sizes. For example, in case of RAPD markers the size range was found to be 200- 1500 bp; whereas, for ISSR markers it was found to be in the range of 400-2000 bp. Interestingly, we found some degree of polymorphism in a few Jatropha accessions, namely TJS 04 #42, TJS 50 #01, TJS 19 #04, TJS 07 #05, TJS 01 #01.