High efficiency and reliability of inter-simple sequence repeats (ISSR) markers for evaluation of genetic diversity in Brazilian cultivated Jatropha curcas L. accessions

Abstract

Jatropha curcas L. is found in all tropical regions and has garnered lot of attention for its potential as a source of biodiesel. As J. curcas is a plant that is still in the process of being domesticated, interest in improving its agronomic traits has increased in an attempt to select more productive varieties, aiming at sustainable utilization of this plant for biodiesel production. Therefore, the study of genetic diversity in different accessions of J. curcas in Brazil constitutes a necessary first step in genetic programs designed to improve this species. In this study we have used ISSR markers to assess the genetic variability of 332 accessions from eight states in Brazil that produce J. curcas seeds for commercialization. Seven ISSR primers amplified a total of 21,253 bands, of which 19,472 bands (91%) showed polymorphism. Among the polymorphic bands 275 rare bands were identified (present in fewer than 15% of the accessions). Polymorphic information content (PIC), marker index (MI) and resolving power (RP) averaged 0.26, 17.86 and 19.87 per primer, respectively, showing the high efficiency and reliability of the markers used. ISSR markers analyses as number of polymorphic loci, genetic diversity and accession relationships through UPGMA-phenogram and MDS showed that Brazilian accessions are closely related but have a higher level of genetic diversity than accessions from other countries, and the accessions from Natal (RN) are the most diverse, having high value as a source of genetic diversity for breeding programs of J. curcas in the world.

Genetic structure from the oldest Jatropha germplasm bank of Brazil and contribution for the genetic improvement

“…Alkimim et al (2013) evaluated jatropha accessions from Minas Gerais using ISSR and RAPD markers and reported low genetic diversity. These results are also similar to those obtained in studies using ISSR markers in Brazil (Grativol et al 2011) and in different countries, such as China (Chen et al 2011) andIndia (Kumar et al 2011).…”

Evaluation of genetic homogeneity of Jatropha curcas L. hybrid at an early stage of shoot bud formation from petioles using ISSR marker

“…These results are in agreement with the study by Zhang et al [15], where the same concentration of 1.0 mg/L of TDZ is also reported to give highest shoot bud formation ( Table 2). All the primers (Table 3) applied in this study were selected according to Grativol et al [28] and Kumar et al [29]. In total, 23 ISSR primers were screened for amplified bands, but 16 primers were chosen for further analysis, as they generated 96 clear and reproducible amplification products.…”

“…Some molecular methods have been previously applied for genetic stability studies in J. curcas, such as the use of amplified fragment length polymorphisms (AFLPs) [23], random amplified polymorphic DNA (RAPD) [24] and flow cytometry [25]. The use of inter simple sequence repeats (ISSRs) offers unique advantages over other molecular markers, since their application does not require any genomic information of the target species, it only requires a small amount of template DNA, is rapidly performed [26] and is highly efficient in detecting highly polymorphic DNA among Jatropha genotypes [27,28]. An ISSR marker system has been successfully used to detect somaclonal variation in J. curcas [25,29,30].…”

Genetic diversity and geographic differentiation analysis of duckweed using inter-simple sequence repeat markers

“…ISSR has a few advantages over other DNA marker techniques. It has been shown to provide a powerful, rapid, simple, reproducible and inexpensive means of assessing genetic diversity and identify closely related cultivars in many species [16,[21][22][23]. Consequently, ISSR may reveal more polymorphic fragments with each primer than are revealed by random amplified polymorphic DNA (RAPD) [24,25].…”