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

Abstract

Jatropha is a potential oilseed crop, which requires mitigating factors such as the low genetic variability of the species. The solution runs through the research of Brazilian germplasm. Attention should be given to the germplasm of jatropha the north of Minas Gerais, because this is the oldest national collection and because this region may be a regions of jatropha diversity due to selection pressure arising from environmental adversities. Therefore, the objective of this study was to investigate the genetic diversity of 48 accessions of collection from Empresa de Pesquisa Agropecuária de Minas Gerais (EPAMIG), using SSR and ISSR markers. The results showed low genetic diversity, but some individuals stood out as J. mollissima (48), J. podagrica (47), Mexican accessions (42, 43, 44 and 45) and some national accessions (28, 29, 41 and 46). Therefore, aiming to increase the genetic variability and improve the effectiveness of jatropha breeding programs, it is suggested to explore such as parental accessions to generate commercial hybrids. This fact implies the possibility to support future production of jatropha, since this culture may be an important source of income, especially for small farmers living in semiarid regions of Brazil.

Genetic variability revealed by microsatellite markers in a germplasm collection of Jatropha curcas L. in Brazil: an important plant for biofuels

“…In addition to estimating the number of polymorphic loci, other quantitative measures can be adopted, such as Ho and He, which allow to infer about the genetic structure of the population. The means of Ho and He in the present study (Ho=0.64 and He=0.40) were similar to those found by Santos et al (2016). Bressan et al (2012) also reported similar values (Ho=0.53 and He=0.66) for these measures, although with He higher than Ho, in a direction contrary to that verified in the present study and by Santos et al (2016).…”

“…Regarding the genetic variability statistics obtained here, the number of alleles per loci (na), ranged from 2 to 3 (mean=2.2), was similar to that found by several other authors. Santos et al (2016), using 11 SSR markers, found 2 to 5 alleles per locus, whereas Bressan et al (2012) found 2 to 8 alleles per locus. However, Na-ek et al (2011) identified only 1.4 alleles per locus, after evaluating 32 accessions.…”

“…Sudheer et al (2009) used SSR markers to characterize germplasm from India. Santos et al (2016) evaluated genetic variability using SSR and ISSR markers in 48 accessions from northern Minas Gerais state, Brazil.…”

“…Microsatellites, also known as Simple Repeated Sequence (SSR) markers, have high reproducibility, codominant inheritance and high polymorphism. Studies involving these markers have been successfully used to characterize the genetic variability of J. curcas (Pamidimarri et al 2008, Sun et al 2008, Sudheer et al 2009, Rosado et al 2010, Wen et al 2010, Bressan et al 2012, Na-ek et al 2011, Pecina-Quintero et al 2014, Sinha et al 2015, Santos et al 2016, Vásquez-Mayorga et al 2017, Gangapur et al 2018. In all of these studies, the genetic variability revealed for this species has been considered low.…”

WIDE GENETIC VARIABILITY WITHIN AND AMONG FAMILIES IN A GERMPLASM COLLECTION OF Jatropha curcas L. AS REVEALED BY MICROSATELLITE MARKERS

“…Several studies on genetic diversity in J. curcas using SSR markers have been conducted (Sudheer Pamidimarri et al, 2009;Rosado et al, 2010;Wen et al, 2010;Na-ek et al, 2011;Bressan et al, 2012;Pecina-Quintero et al, 2014;Salvador-Figueroa et al, 2014;Alves et al, 2015;Sinha et al, 2015;Santos et al, 2016;Ribeiro et al, 2017;Vásquez-Mayorga et al, 2017;Gangapur et al, 2018;Souza et al, 2019).…”