Potential use of random amplified polymorphic DNA (RAPD) technique to study the genetic diversity in Indian mustard (Brassica juncea) and its relationship to heterosis

Abstract

RAPD assays were performed, using 34 arbitrary decamer oligonucleotide primers and six combinations of two primers, to detect inherent variations and genetic relationships among 12 Indian and 11 exotic B. juncea genotypes. Of 595 amplification products identified, 500 of them were polymorphic across all genotypes. A low level of genetic variability was detected among the Indian genotypes, while considerable polymorphism was present among the exotic ones. Based on the pair-wise comparisons of amplification products the genetic similarity was calculated using Jaccard's similarity coefficients and a dendrogram was constructed using an unweighted pair group method was arithmetical averages (UPGMA). On the basis of this analysis the genotypes were clustered into two groups, A and B. Group A comprised only exotic genotypes, whereas all the Indian genotypes and four of the exotic genotypes were clustered in group B. Almost similar genotypic rankings could also be established by computing as few as 200 amplification products. In general, a high per cent of heterosis was recorded in crosses involving Indian x exotic genotypes. On the other hand, when crosses were made amongst Indian or exotic genotypes, about 80% of them exhibited negative heterosis. Results from this study indicate that, despite the lack of direct correlation between the genetic distance and the degree of heterosis, genetic diversity forms a very useful guide not only for investigating the relationships among Brassica genotypes but also in the selection of parents for heterotic hybrid combinations.

SSR analysis of 38 genotypes of soybean (Glycine Max (L.) Merr.) genetic diversity in India

“…Such markers are highly reliable in the establishment of genetic relatedness among the genotypes. Similar results were reported by Jain et al (1994), Srivastava et al (2001), and Vinu et al (2013) in different crop species. PIC value is a measure of the allelic differentiation.…”

Assessment of Genetic Variation in Indian Mustard (<i>Brassica juncea</i> L.) Using PCR Based Markers

“…RAPD-like assays can search large genomic portions due to their abundant distribution in the genome and there by presenting a more accurate picture of genetic variation within the crop plants in an efficient and inexpensive ways (Souframanien and Gopalakrishna, 2004). RAPD markers have been successfully used to evaluate genetic diversity in Brassica (Demeke et al, 1992;Jain et al, 1994;Thormann et al, 1994;Bhatia et al, 1995;Dulson et al, 1998;Zu and Wu, 1998;Divaret et al, 1999), common wheat (Liu et al, 1999;Sivolap et al, 1997), maize (Zhang et al, 1998;Bernado et al, 1997), barley (Hamza et al, 2004) and sesame (Salazar et al, 2007). The number of markers used, their abundance in the genome and the degree of precision with which the results are analyzed determine the accuracy to distinguish the genotypes (Schut et al, 1997).…”

Variabilidade genética em acessos de caupi analisada por meio de marcadores RAPD

“…A amplitude de bandas polimórficas variou de 33% a 100%, semelhante ao que foi observado por Jain et al (1994). O número de bandas por iniciador variou entre três e nove, com tamanho entre 400 pb a 1.500 pb.…”

“…A maior parte das variedades locais estudadasGalanjão-CE, Seridó, Canapu-RV-1, Lisão, Canapu-RV-2, Paulista e Paulistão -encontram-se no grupo I, o que sugere uma origem estreita do germoplasma em uso no Brasil. Resultados similares foram obtidos com acessos exóti-cos e cultivares da Índia (Jain et al, 1994), em que os exóticos apresentaram maior polimorfismo, formando um grupo isolado. Bezerra (1997), ao estudar acessos de caupi, identificou grupos que apresentaram produtividade acima de 2.500 kg ha -1 .…”